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  • 1.
    Bastami, Salumeh
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Haage, Pernilla
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences.
    Kronstrand, Robert
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences.
    Kugelberg, Fredrik C.
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences.
    Zackrisson, Anna Lena
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences.
    Uppugunduri, Srinivas
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Chemistry.
    Influence of genetic polymorphism on tramadol pharmacokinetics and pharmacodynamicsManuscript (preprint) (Other academic)
    Abstract [en]

    Purpose: There is a significant interindividual variation in the response to tramadol (TRA), which can partly be explained by genetic variation. The main purpose of this study was to determine if there is a correlation between the metabolic ratio of O-desmethyltramadol (ODT) to TRA (MR) and time after drug administration. We also studied the association between genetic polymorphisms in CYP2D6, OPRM1 and ABCB1 and pharmacokinetic and pharmacodynamic properties of TRA.

    Methods: Nineteen healthy volunteers were randomized into two groups receiving a single dose of either 50 or 100 mg of orally administrated TRA. Blood samples were collected prior to dosing and up to 72 h after drug intake. The subjects were asked to report drug related symptoms (DRS) during the experimental day.

    Results: We found a positive correlation between MR and the time after drug intake for both intermediate metabolizers (IMs) and extensive metabolizers (EMs). For the only poor metabolizer (PM) with detectable ODT levels the MR was almost constant. The AUC MR and Cmax MR were associated with CYP2D6 genotype, showing the highest mean values for EMs. Multiple regression analysis showed that 56% of the  variation in AUC MR could be explained by CYP2D6 alone and 78% by investigated SNPs altogether. There was great interindividual variation in DRS, but no associations could be found between DRS and investigated polymorphisms.

    Conclusions: MR can be used for estimation of the time of drug intake when the CYP2D6 genotype is known and taken into consideration. The influence of genetic polymorphisms in ABCB1 and OPRM1 requires further study. We propose that pharmacogenetics should be taken into consideration when interpreting clinical pharmacology and forensic toxicology results, more specifically CYP2D6 genotypes when interpreting the pharmacokinetics of TRA.

  • 2.
    Bastami, Salumeh
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences.
    Haage, Pernilla
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences. National Board of Forensic Medicine, Department of Forensic Genetics and Forensic Toxicology, Linköping, Sweden.
    Kronstrand, Robert
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences. National Board of Forensic Medicine, Department of Forensic Genetics and Forensic Toxicology, Linköping, Sweden.
    Kugelberg, Fredrik
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences. National Board of Forensic Medicine, Department of Forensic Genetics and Forensic Toxicology, Linköping, Sweden.
    Zackrisson, Anna-Lena
    National Board of Forensic Medicine, Department of Forensic Genetics and Forensic Toxicology, Linköping, Sweden.
    Uppugunduri, Srinivas
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Chemistry.
    Pharmacogenetic aspects of tramadol pharmacokinetics and pharmacodynamics after a single oral dose2014In: Forensic Science International, ISSN 0379-0738, E-ISSN 1872-6283, Vol. 238, p. 125-132Article in journal (Refereed)
    Abstract [en]

    The major purpose of this study was to elucidate if genotyping can facilitate interpretations of tramadol (TRA) in forensic case work, with special regard to the estimation of the time of drug intake and drug related symptoms (DRS). The association between genetic polymorphisms in CYP2D6, OPRM1 and ABCB1 and pharmacokinetic and pharmacodynamic properties of TRA was studied. Nineteen healthy volunteers were randomized into two groups receiving a single dose of either 50 or 100 mg of orally administrated TRA. Blood samples were collected prior to dosing and up to 72 h after drug intake. The subjects were asked to report DRS during the experimental day. We found a positive correlation between the metabolic ratio of O-desmethyltramadol (ODT) to TRA and the time after drug intake for both CYP2D6 intermediate metabolizers and extensive metabolizers. For the only poor metabolizer with detectable ODT levels the metabolic ratio was almost constant. Significant associations were found between the area under the concentration-time curve (AUC) and three of the investigated ABCB1 single nucleotide polymorphisms for TRA, but not for ODT and only in the 50 mg dosage group. There was great interindividual variation in DRS, some subjects exhibited no symptoms at all whereas one subject both fainted and vomited after a single therapeutic dose. However, no associations could be found between DRS and investigated polymorphisms. We conclude that the metabolic ratio of ODT/TRA may be used for estimation of the time of drug intake, but only when the CYP2D6 genotype is known and taken into consideration. The influence of genetic polymorphisms in ABCB1 and OPRM1 requires further study.

  • 3.
    Bengtsson, Finn
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Pharmacology.
    Kugelberg, Fredrik
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology.
    Fate of psychotropic drugs at the blood-brain-barrier and the brain: pharmacokinetic, pharmacodynamic and clinical consequences2005In: Association of European Psychiatrists AEP Congress,2005, 2005Conference paper (Other academic)
  • 4.
    Boiso, Samuel
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences.
    Zackrisson, Anna Lena
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Jakobsen Falk, Ingrid
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences.
    Karlsson, Louise
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences.
    Carlsson, Björn
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Pharmacology.
    Tillmar, Andreas
    Natl Board Forens Med, Dept Forens Genet and Forens Toxicol, Linkoping, Sweden .
    Kugelberg, Fredrik
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences.
    Ahlner, Johan
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences.
    Hägg, Staffan
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Pharmacology.
    Green, Henrik
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences.
    ABCB1 gene polymorphisms are associated with suicide in forensic autopsies2013In: Pharmacogenetics & Genomics, ISSN 1744-6872, E-ISSN 1744-6880, Vol. 23, no 9, p. 463-469Article in journal (Refereed)
    Abstract [en]

    Background Polymorphisms in ABCB1 have the ability to affect both the function and the expression of the transporter protein P-glycoprotein and may lead to an altered response for many drugs including some antidepressants and antipsychotics.Objective The aim of this study was to examine the impact of the ABCB1 polymorphisms 1199Gandgt;A, 1236Candgt;T, 2677Gandgt;T/A, and 3435Candgt;T in deaths by suicide.Patients and methods A total of 998 consecutive Swedish forensic autopsies performed in 2008 in individuals 18 years of age or older, where femoral blood was available and a toxicological screening had been performed, were investigated. Genotypes were assessed with pyrosequencing and information on the cause and manner of each death was obtained from the forensic pathology and toxicology databases.Results There was a significantly higher frequency of the T allele at positions 1236, 2677, and 3435 among the suicide cases compared with the nonsuicide cases.Conclusion Our result from forensic cases suggests that ABCB1 polymorphisms are associated with an increased risk for completed suicides. The biological mechanisms involved and the clinical implications for these findings are largely unknown and need to be examined further.

  • 5.
    Druid, H
    et al.
    Rättsmedicin KI.
    Strandberg, J
    Rättsmedicin KI.
    Nyström, I
    Rättskemi RMV.
    Alkass, K
    Rättsmedicin KI.
    Kugelberg, Fredrik
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology.
    Kronstrand, R
    Rättskemi RMV.
    Drug exposure pattern in hair and femoral blood in deceased drug addicts2005In: Joint SOFT/TIAFT/FBI meeting on Forensic Toxicology,2005, Niles, Illinois, USA: Preston publications , 2005, p. 504-Conference paper (Refereed)
  • 6. Druid, H
    et al.
    Strandberg, J
    Nyström, I
    Alkass, K
    Kugelberg, Fredrik
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology.
    Kronstrand, R
    Drug exposure pattern in hair and femoral blood in deceased drug addicts2004In: SOFTTIAFT,2004, 2004, p. 365-365Conference paper (Other academic)
  • 7.
    Druid, Henrik
    et al.
    Rättsmedicin, KI Stockholm.
    Holmgren, Per
    Kugelberg, Fredrik
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology.
    Blodförlust ökar halten av kodein och morfin i blod.2002In: Svenska Läkaresällskapets Handlingar,2002, 2002, p. 314-314Conference paper (Refereed)
  • 8.
    Druid, Henrik
    et al.
    Department of Forensic Medicine, Karolinska Institutet, Stockholm, Sweden.
    Strandberg, Joakim J.
    Department of Forensic Medicine, Karolinska Institutet, Stockholm, Sweden.
    Alkass, Kanar
    Department of Forensic Medicine, Karolinska Institutet, Stockholm, Sweden.
    Nyström, Ingrid
    Department of Forensic Toxicology, National Board of Forensic Medicine, Linköping, Sweden.
    Kugelberg, Fredrik
    Department of Forensic Medicine, Karolinska Institutet, Stockholm, Sweden.
    Kronstrand, Robert
    Department of Forensic Toxicology, National Board of Forensic Medicine, Linköping, Sweden.
    Evaluation of the role of abstinence in heroin overdose deaths using segmental hair analysis2007In: Forensic Science International, ISSN 0379-0738, E-ISSN 1872-6283, Vol. 168, no 2-3, p. 223-226Article in journal (Refereed)
    Abstract [en]

    In the body heroin is rapidly metabolized to 6-acetylmorphine and morphine. Victims of lethal heroin overdose often present with fairly low blood concentrations of morphine. Reduced tolerance due to abstinence has been proposed to account for this finding. The aim of the present study was to examine the role of abstinence in drug-related deaths by comparing recent and past exposure to opioids using segmental hair analysis with the postmortem blood morphine concentrations in deceased heroin users. The study included 60 deceased drug addicts in the Stockholm area, Sweden. In 32 cases, death was not related to heroin intake. In 18 of the 28 heroin fatalities, opioids were absent in the most recent hair segment, suggesting a reduced tolerance to opioids. However, the blood morphine levels were similar to those found in the 10 subjects that showed continuous opioid use. Hair and blood analysis disclosed an extensive use of additional drugs that directly or indirectly may influence the opioid system. The results suggest that abstinence is not a critical factor for heroin overdose death. Obviously tolerant subjects die after intake of similar doses. Other factors, particularly polydrug use, seem to be more causally important for these deaths.

  • 9.
    Elmsjo, Albert
    et al.
    Natl Board Forens Med, Dept Forens Genet & Forens Toxicol, S-58758 Linkoping, Sweden.
    Vikingsson, Svante
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Clinical Chemistry and Pharmacology. Linköping University, Faculty of Medicine and Health Sciences. RTI Int, NC 27709 USA.
    Soderberg, Carl
    Natl Board Forens Med, Dept Forens Genet & Forens Toxicol, S-58758 Linkoping, Sweden.
    Kugelberg, Fredrik
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Clinical Chemistry and Pharmacology. Linköping University, Faculty of Medicine and Health Sciences. Natl Board Forens Med, Dept Forens Genet & Forens Toxicol, S-58758 Linkoping, Sweden.
    Green, Henrik
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Clinical Chemistry and Pharmacology. Linköping University, Faculty of Medicine and Health Sciences. Natl Board Forens Med, Dept Forens Genet & Forens Toxicol, S-58758 Linkoping, Sweden.
    Post-Mortem Metabolomics: A Novel Approach in Clinical Biomarker Discovery and a Potential Tool in Death Investigations2021In: Chemical Research in Toxicology, ISSN 0893-228X, E-ISSN 1520-5010, Vol. 34, no 6, p. 1496-1502Article in journal (Refereed)
    Abstract [en]

    Metabolomics can be defined as the scientific field aiming at characterizing all low-weight molecules (so-called metabolites) in a biological system. At the time of death, the level and type of metabolites present will most likely reflect the events leading up to death. In this proof of concept study, we investigated the potential of post-mortem metabolomics by identifying post-mortem biomarkers, correlated these identified biomarkers with those reported in clinical metabolomics studies, and finally validated the models predictability of unknown autopsy cases. In this post-mortem metabolomics setting, ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry data from 404 post-mortem samples, including pneumonia cases and control cases, were processed using XCMS (R). Potential biomarkers were evaluated using principal component analysis and orthogonal partial least squares-discriminant analysis. Biomarkers were putatively annotated using an in-house database and the online databases METLIN and HMDB. The results showed that clear group separation was observed between pneumonia cases and control cases. The metabolites responsible for group separation belonged to a broad set of biological classes, such as amino acids, carnitines, lipids, nicotinamides, nucleotides, and steroids. Many of these metabolites have been reported as important in clinical manifestation of pneumonia. For the unknown autopsy cases, the sensitivity and specificity were 86 and 84%, respectively. This study successfully investigated the robustness and usability of post-mortem metabolomics in death investigations. The identified post-mortem biomarkers correlated well with biomarkers reported and identified through clinical research.

  • 10.
    Grass, Johanna Nordmark
    et al.
    Swedish Poisons Informat Ctr, Sweden.
    Ahlner, Johan
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Natl Board Forens Med, Dept Forens Genet and Forens Toxicol, Linkoping, Sweden.
    Kugelberg, Fredrik
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Natl Board Forens Med, Dept Forens Genet and Forens Toxicol, Linkoping, Sweden.
    Steinwall, Johanna
    Stockholm South Gen Hosp, Sweden.
    Forsman, Par
    Karolinska Univ Hosp, Sweden.
    Lindeman, Erik
    Swedish Poisons Informat Ctr, Sweden.
    Letter: A case of massive metoprolol and amlodipine overdose with blood concentrations and survival following extracorporeal corporeal membrane oxygenation (ECMO) in CLINICAL TOXICOLOGY, vol 57, issue 1, pp 66-682019In: Clinical Toxicology, ISSN 1556-3650, E-ISSN 1556-9519, Vol. 57, no 1, p. 66-68Article in journal (Other academic)
    Abstract [en]

    n/a

  • 11.
    Haage, Pernilla
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences.
    Kronstrand, Robert
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences.
    Josefsson, Martin
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
    Calistri, Simona
    Department of Clinical Chemistry, Erasmus University Medical Center, Rotterdam, The Netherlands / Scuola di Scienze della Salute Umana, Università degli studi di Firenze, Florence, Italy.
    van Schaik, Ron H N
    Department of Clinical Chemistry, Erasmus University Medical Center, Rotterdam, The Netherlands.
    Green, Henrik
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences.
    Kugelberg, Fredrik
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences.
    Enantioselective pharmacokinetics of tramadol and its three main metabolites; impact of CYP2D6, CYP2B6, and CYP3A4 genotype2018In: Pharmacology Research & Perspectives, E-ISSN 2052-1707, Vol. 6, no 4, article id e00419Article in journal (Refereed)
    Abstract [en]

    Tramadol is a complex drug, being metabolized by polymorphic enzymes and administered as a racemate with the (+)- and (-)-enantiomers of the parent compound and metabolites showing different pharmacological effects. The study aimed to simultaneously determine the enantiomer concentrations of tramadol, O-desmethyltramadol, N-desmethyltramadol, and N,O-didesmethyltramadol following a single dose, and elucidate if enantioselective pharmacokinetics is associated with the time following drug intake and if interindividual differences may be genetically explained. Nineteen healthy volunteers were orally administered either 50 or 100 mg tramadol, whereupon blood samples were drawn at 17 occasions. Enantiomer concentrations in whole blood were measured by LC-MS/MS and the CYP2D6,CYP2B6 and CYP3A4 genotype were determined, using the xTAG CYP2D6 Kit, pyrosequencing and real-time PCR, respectively. A positive correlation between the (+)/(-)-enantiomer ratio and time following drug administration was shown for all four enantiomer pairs. The largest increase in enantiomer ratio was observed for N-desmethyltramadol in CYP2D6 extensive and intermediate metabolizers, rising from about two to almost seven during 24 hours following drug intake. CYP2D6 poor metabolizers showed metabolic profiles markedly different from the ones of intermediate and extensive metabolizers, with large area under the concentration curves (AUCs) of the N-desmethyltramadol enantiomers and low corresponding values of the O-desmethyltramadol and N,O-didesmethyltramadol enantiomers, especially of the (+)-enantiomers. Homozygosity of CYP2B6 *5 and *6 indicated a reduced enzyme function, although further studies are required to confirm it. In conclusion, the increase in enantiomer ratios over time might possibly be used to distinguish a recent tramadol intake from a past one. It also implies that, even though (+)-O-desmethyltramadol is regarded the enantiomer most potent in causing adverse effects, one should not investigate the (+)/(-)-enantiomer ratio of O-desmethyltramadol in relation to side effects without consideration for the time that has passed since drug intake.

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  • 12.
    Hoiseth, G.
    et al.
    Oslo Univ Hosp, Norway; Diakonhjemmet Hosp, Norway; Univ Oslo, Norway.
    Nilsson, G. H.
    Natl Board Forens Med, Dept Forens Genet & Forens Toxicol, Linkoping, Sweden.
    Lundberg, R.
    Natl Board Forens Med, Dept Forens Genet & Forens Toxicol, Linkoping, Sweden.
    Forsman, M.
    Natl Board Forens Med, Dept Forens Genet & Forens Toxicol, Linkoping, Sweden.
    Kronstrand, C
    Linköping University, Faculty of Medicine and Health Sciences.
    Nystrom, I
    Natl Board Forens Med, Dept Forens Genet & Forens Toxicol, Linkoping, Sweden.
    Oscarsson, C.
    Natl Board Forens Med, Dept Forens Genet & Forens Toxicol, Linkoping, Sweden.
    Ericsson, E.
    Natl Board Forens Med, Dept Forens Genet & Forens Toxicol, Linkoping, Sweden.
    Cherma, M. D.
    Natl Board Forens Med, Dept Forens Genet & Forens Toxicol, Linkoping, Sweden.
    Ahlner, Johan
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Natl Board Forens Med, Dept Forens Genet & Forens Toxicol, Linkoping, Sweden.
    Kugelberg, Fredrik
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Natl Board Forens Med, Dept Forens Genet & Forens Toxicol, Linkoping, Sweden.
    Kronstrand, Robert
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Natl Board Forens Med, Dept Forens Genet & Forens Toxicol, Linkoping, Sweden.
    Evaluating the hip-flask defence using analytical data from ethanol and ethyl glucuronide. A comparison of two models2020In: Forensic Science International, ISSN 0379-0738, E-ISSN 1872-6283, Vol. 316, article id 110409Article in journal (Refereed)
    Abstract [en]

    Aim: Claimed intake of alcohol after a traffic incident, called the hip-flask defence, can be objectively assessed by different methods. One of them is the use of two consecutive ethanol concentrations in urine and the ratio between ethanol concentrations in urine and blood. Another one is the concentrations of ethyl glucuronide (EtG) and ethyl sulphate (EtS) in blood and their ratio to ethanol. The experimental basis for both these models is from single dose studies only. The aim of this study was therefore to describe the kinetics of ethanol, EtG and EtS after ingestion of two repeated doses of ethanol and to investigate the usefulness of the different models for the assessment of the hip-flask defence. Methods: Thirty-five subjects ingested a first dose of 0.51 g of ethanol per kilo body weight, and two hours later a second dose (the hip-flask drink) of 0.25, 0.51 or 0.85 g of ethanol per kilo body weight. Ten urine and 17 blood samples were collected and analysed for ethanol, EtG and EtS using fully validated methods. It was investigated if all subjects fulfilled the criteria for recent drinking, according to the two different models, when using the samples collected 180-240 minutes after start of first dose drinking. According to the first model, increase in urinary ethanol concentrations and a ratio UAC/BAC below 1.3 indicated recent drinking. According to the second model, increase in blood EtG concentrations and a ratio ethanol (g/kg)/EtG (mg/L) above 1 indicated recent drinking. Results: All subjects in the high dose group fulfilled all criteria for recent drinking. One subject in the medium dose group and nine subjects in the low dose group failed to show increasing UAC and/or a UAC/ BAC ratio below 1.3. One subject in the low dose group failed to show increasing concentrations of blood EtG, but all subjects showed a ratio ethanol/EtG above 1. Conclusions: The present study showed, by the use of experimental data, that both two models used to investigate the hip-flask defence can be used, but only when the hip-flask dose is sufficiently high. (C) 2020 The Author(s). Published by Elsevier B.V.

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  • 13. Holmgren, A
    et al.
    Holmgren, P
    Kugelberg, Fredrik
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology.
    Jones, A Wayne
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of clinical chemistry.
    Ahlner, Johan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology.
    Predominance of illicit drugs and poly-drug use among drug-impaired drivers in Sweden2007In: Traffic Injury Prevention, ISSN 1538-9588, E-ISSN 1538-957X, Vol. 8, no 4, p. 361-367Article in journal (Refereed)
    Abstract [en]

    Objective. After Sweden's zero-tolerance law came into force (1 July 1999), the number of cases of driving under the influence of drugs (DUID) submitted by the police for toxicological analysis increased more than 10-fold. This prompted an in-depth investigation into the kinds of drugs used by DUID offenders, whether licit or illicit, and the frequency of their occurrence. Methods. All blood samples from DUID suspects sent by the police for toxicological analysis over a 4-year period (2001-2004) were investigated (N = 22,777 cases). Specimens of blood or urine were subjected to a broad screening analysis by immunoassay methods aimed at detecting amphetamines, cannabis, opiates, cocaine metabolite, and the major benzodiazepines. All positive results from the screening stage were verified by use of more specific analytical methods (e.g., GC-MS, LC-MS, GC-FID, and GC-NPD). Results. Between 80 and 85% of all the blood samples contained at least one banned substance and many contained two or more therapeutic and/or illicit drugs. About 15% of cases were negative for drugs, although these frequently (30-50%) contained ethanol above the legal limit for driving in Sweden, which is 0.20 mg/g (0.02 g%). Amphetamine was the most prominent illicit drug seen in 55-60% of cases either alone or together with other drugs of abuse. Stimulants like cocaine and/or its metabolite were infrequently encountered (1.2% of cases). The next most prevalent illicit drug was cannabis, with positive results for tetrahydrocannabinol (THC) in blood either alone (4%) or together with other psychoactive substances (20%). Morphine, codeine, and/or 6-acetyl morphine were identified in 2% of all DUID suspects, being indicative of heroin abuse. The major prescription drugs identified in blood were benzodiazepines (10%) as exemplified by diazepam, alprazolam, nitrazepam, and flunitrazepam. Drugs for treating insomnia, zolpidem and zopiclone, were also identified in blood samples from DUID suspects over the study period. Other therapeutic agents were encountered in only 1-2% of all cases. Conclusions. The dramatic increase in DUID after the zero-tolerance law came into force probably reflects enhanced police activity and more enthusiasm to apprehend and charge individuals for this offence. Illicit drugs, particularly amphetamine and cannabis, and poly-drug use were predominant compared with use of scheduled prescription drugs. The typical DUID offender in Sweden abuses central stimulants, particularly amphetamine, and has probably done so over many years. Options for treating offenders for their underlying substance abuse problem should be considered instead of the more conventional penalties for drug-impaired driving.

  • 14.
    Holmgren, Anita
    et al.
    Department of Forensic Genetics and Forensic Toxicology National Board of Forensic Medicine, Linköping.
    Holmgren, Per
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology.
    Kugelberg, Fredrik
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology.
    Jones, A Wayne
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry.
    Ahlner, Johan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology.
    High re-arrest rates among drug-impaired drivers despite zero-tolerance legislation2008In: Accident Analysis and Prevention, ISSN 0001-4575, E-ISSN 1879-2057, Vol. 40, no 2, p. 534-540Article in journal (Refereed)
    Abstract [en]

    Background: A zero-tolerance law for driving under the influence of drugs (DUID) in Sweden led to a 10-fold increase in the number of cases submitted by the police for toxicological analysis. The statutory blood-alcohol concentration (BAC) limit for driving is 0.2 mg/g (∼0.02 g%). Methods: An in-house database (TOXBASE) was used to investigate re-arrests for impaired driving over 4 years (2001-2004), which comprised 36,799 cases. The age, gender, re-arrest rate of the offenders and the concentrations of ethanol and amphetamine in blood samples were evaluated. Results: We found that 44% of individuals (N = 16,277) re-offended 3.2 times on average (range 1-23 arrests). Between 85 and 89% of first-time offenders were men and there was also a male dominance among the recidivists (88-93%). The mean age of drunken drivers was ∼40 years compared with ∼35 years for driving under the influence of amphetamine, which was the drug identified in 50-60% of DUID cases, either alone or together with other licit or illicit drugs. The median BAC was 1.5 mg/g (∼0.15 g%), which suggests a dominance of heavy drinkers. The median BAC was even higher in recidivists (1.6-1.7 mg/g). The median concentration of amphetamine in blood was 1.0 mg/L in recidivists compared with 0.5 mg/L in the first-time offenders. About 14% of drunken drivers re-offended 1-10 times compared with 68% of DUID suspects, who were re-arrested 1-23 times. People with only a scheduled prescription drug in blood were re-arrested much less frequently (∼17%) compared with those taking illicit drugs (68%). Conclusions: The appreciable increase in number of arrests for DUID after a zero-tolerance law might reflect a heightened enthusiasm by the police authorities armed with knowledge that a prosecution is easier to obtain. Zero-tolerance laws do not deter people from impaired driving judging by the high re-arrest rates. During the sentencing of hardcore offenders, the courts should give more consideration to the underlying substance abuse problem. © 2007 Elsevier Ltd. All rights reserved.

  • 15.
    Johansen, Sys Stybe
    et al.
    Univ Copenhagen, Denmark.
    Tuong Vy Le Dang, Linda
    Univ Copenhagen, Denmark.
    Nielsen, Marie Katrine Klose
    Univ Copenhagen, Denmark.
    Haage, Pernilla
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences.
    Kugelberg, Fredrik
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences.
    Kronstrand, Robert
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences.
    Temporal patterns of tramadol in hair after a single dose2020In: Forensic Science International, ISSN 0379-0738, E-ISSN 1872-6283, Vol. 316, article id 110546Article in journal (Refereed)
    Abstract [en]

    This controlled study aimed to measure concentrations of tramadol (TRA) and its two main metabolites, N-desmethyltramadol (NDMT) and O-desmethyltramadol (ODMT), in hair following a single dose ingestion and to investigate the distribution patterns in hair by segmental analysis of hair samples taken at several sampling time points after ingestion. An oral dose (50 or 100 mg) of TRA was administered to 17 healthy volunteers. Hair samples were collected prior to drug administration and 14, 30, 60 and 120 days after ingestion. Each sample was segmented in 5 mm segments and washed. The analytes were extracted from pulverized hair by incubation in extraction media for 18 h at 37 degrees C. A validated UHPLC-MS/MS method was used to quantify the analytes at a LLOQ of 0.001 ng/mg. Hair segments corresponding to the time of ingestion were positive for TRA and the metabolites of each sampling time point, although neighboring segments also showed positive results. The highest concentrations for both dosage groups were observed in the proximal segment of hair collected 14 days after ingestion for all subjects: 0.061-0.95 ng TRA/mg, 0.012-0.86 ng NDMT/mg and 0.009-0.17 ng ODMT/mg (n = 16). Generally, the TRA concentration was higher than the metabolites concentrations but depended on the CYP2D6 phenotype. The metabolite to TRA ratios were stable within a subject over the sampling time points, however it varied greatly between subjects. No significant differences in hair concentrations were found between the two dosage groups at each sampling time. Several confounding factors were identified such as hair pigmentation and internal sweat. We showed that analysis of 5 mm segments improved the determination of the exposure time after a single ingestion of TRA. In addition, in the later sampling time points the analytes were spread more between segments and the total drug amount of each later sampling time point declined up to a 100% (median: 75%) due to wash out. The presented results are important additions to the sparse literature reporting single dose of psychoactive drugs in hair. (C) 2020 Elsevier B.V. All rights reserved.

  • 16.
    Johansson, Anna
    et al.
    Natl Board Forens Med, Dept Forens Genet & Forens Toxicol, Artillerigatan 12, S-58758 Linkoping, Sweden.
    Ahlner, Johan
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Clinical Chemistry and Pharmacology. Linköping University, Faculty of Medicine and Health Sciences.
    Lennborn, Ulrica
    Uppsala Univ, Sweden.
    Nielsen, Elisabet I.
    Uppsala Univ, Sweden.
    Sandler, Hakan
    Natl Board Forens Med, Sweden; Uppsala Univ, Sweden.
    Rubertsson, Sten
    Uppsala Univ, Sweden.
    Kronstrand, Robert
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Clinical Chemistry and Pharmacology. Linköping University, Faculty of Medicine and Health Sciences. Natl Board Forens Med, Dept Forens Genet & Forens Toxicol, Artillerigatan 12, S-58758 Linkoping, Sweden.
    Kugelberg, Fredrik
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Clinical Chemistry and Pharmacology. Linköping University, Faculty of Medicine and Health Sciences. Natl Board Forens Med, Dept Forens Genet & Forens Toxicol, Artillerigatan 12, S-58758 Linkoping, Sweden.
    Quantitation of seven sedative and analgesic drugs in whole blood from intensive care patients using liquid chromatography mass spectrometry2021In: TOXICOLOGIE ANALYTIQUE ET CLINIQUE, ISSN 2352-0078, Vol. 33, no 4, p. 327-337Article in journal (Refereed)
    Abstract [en]

    We present the development and validation of a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for quantification of clonidine, dexmedetomidine, fentanyl, ketamine, ketobemidone, midazolam and morphine in whole blood. These are drugs predominately used in intensive care units (ICUs) but they are also encountered in forensic investigations. The analytes were recovered from 0.25 g of blood by protein precipitation with a mixture of acetonitrile and ethanol. Separation was performed on a BEH phenyl column. Mobile phases consisted of 0.05% formic acid in 10 mM ammonium formate and 0.05% formic acid in methanol, respectively, and the flow rate was 600 mu L/min. The mass spectrometer was operated in positive electrospray ionization mode with multiple reaction monitoring. Validation included selectivity, qualitative matrix effects, calibration model, limit of detection, lower limit of quantification, within- and between-day accuracy and precision, process efficiency, dilution integrity, carry over and stability. Selectivity was high and no ion suppression or enhancementwas observed in the areas were the analytes eluted. Calibration curves were linear over arange of 0.25-50 ng/g for dexmedetomidine, 0.05-50 ng/g for fentanyl and 5.0-500 ng/g formorphine and quadratic over a range of 0.5-50 ng/g for clonidine, 50-5000 ng/g for ketamine, 5.0-500 ng/g for ketobemidone and midazolam. The method showed acceptable within- and betweenday accuracies and precisions. All analytes were stable in whole blood for three weeksat 4. C. Concentrations in patient samples ranged between 42-760 ng/g for midazolam (n = 15), 0.3-1.5 ng/g for dexmedetomidine (n = 13), 0.6-6.4 ng/g for clonidine (n = 13), 8-62 ng/g for morphine (n = 16), 5-19 ng/g for ketobemidone (n = 5), 0.07-3.1 ng/g for fentanyl (n = 43), and 562000 ng/g for ketamine (n = 10). We conclude that the method was successfully validatedand applied to ante-mortem and post-mortem blood samples from critically ill adult patientsin a general ICU. (c) 2021 Societe Francaise de Toxicologie Analytique. Published by Elsevier Masson SAS. Allrights reserved.

  • 17.
    Johansson, Anna
    et al.
    National Board Forens Med, Department Forens Genet and Forens Toxicol, Linkoping, Sweden.
    Lindstedt, Daniel
    National Board Forens Med, Department Forens Genet and Forens Toxicol, Linkoping, Sweden.
    Roman, Markus
    National Board Forens Med, Department Forens Genet and Forens Toxicol, Linkoping, Sweden.
    Thelander, Gunilla
    National Board Forens Med, Department Forens Genet and Forens Toxicol, Linkoping, Sweden.
    Nielsen, Elisabet I.
    Uppsala University, Sweden.
    Lennborn, Ulrica
    Uppsala University, Sweden.
    Sandler, Hakan
    National Board Forens Med, Sweden; Uppsala University, Sweden.
    Rubertsson, Sten
    Uppsala University, Sweden.
    Ahlner, Johan
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. National Board Forens Med, Department Forens Genet and Forens Toxicol, Linkoping, Sweden.
    Kronstrand, Robert
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. National Board Forens Med, Department Forens Genet and Forens Toxicol, Linkoping, Sweden.
    Kugelberg, Fredrik
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. National Board Forens Med, Department Forens Genet and Forens Toxicol, Linkoping, Sweden.
    A non-fatal intoxication and seven deaths involving the dissociative drug 3-MeO-PCP2017In: Forensic Science International, ISSN 0379-0738, E-ISSN 1872-6283, Vol. 275, p. 76-82Article in journal (Refereed)
    Abstract [en]

    Introduction: 3-methoxyphencyclidine (3-MeO-PCP) appeared on the illicit drug market in 2011 and is an analogue of phencyclidine, which exhibits anesthetic, analgesic and hallucinogenic properties. In this paper, we report data from a non-fatal intoxication and seven deaths involving 3-MeO-PCP in Sweden during the period March 2014 until June 2016. Case descriptions: The non-fatal intoxication case, a 19-year-old male with drug problems and a medical history of depression, was found awake but tachycardic, hypertensive, tachypnoeic and catatonic at home. After being hospitalized, his condition worsened as he developed a fever and lactic acidosis concomitant with psychomotor agitation and hallucinations. After 22 h of intensive care, the patient had made a complete recovery. During his hospitalization, a total of four blood samples were collected at different time points. The seven autopsy cases, six males and one female, were all in their twenties to thirties with psychiatric problems and/or an ongoing drug abuse. Methods: 3-MeO-PCP was identified with liquid chromatography (LC)/time-of-flight technology and quantified using LC-tandem mass spectrometry. Results: In the clinical case, the concentration of 3-MeO-PCP was 0.14 mu g/g at admission, 0.08 mu g/g 2.5 h after admission, 0.06 mu g/g 5 h after admission and 0.04 mu g/g 17 h after admission. The half-life of 3-MeO-PCP was estimated to 11 h. In the autopsy cases, femoral blood concentrations ranged from 0.05 mu g/g to 0.38 mu g/g. 3-MeO-PCP was the sole finding in the case with the highest concentration and the cause of death was established as intoxication with 3-MeO-PCP. In the remaining six autopsy cases, other medications and drugs of abuse were present as well. Conclusion: Despite being scheduled in January 2015, 3-MeO-PCP continues to be abused in Sweden. Exposure to 3-MeO-PCP may cause severe adverse events and even death, especially if the user does not receive life-supporting treatment. (C) 2017 Elsevier B. V. All rights reserved.

  • 18.
    Jones, A Wayne
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry.
    Holmgren, A.
    Department of Forensic Genetics and Forensic Toxicology National Board of Forensic Medicine, Linköping.
    Kugelberg, Fredrik
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology.
    Concentrations of cocaine and its major metabolite benzoylecgonine in blood samples from apprehended drivers in Sweden2008In: Forensic Science International, ISSN 0379-0738, E-ISSN 1872-6283, Vol. 177, no 2-3, p. 133-139Article in journal (Refereed)
    Abstract [en]

    Cocaine and its major metabolite benzoylecgonine (BZE) were determined in blood samples from people arrested in Sweden for driving under the influence of drugs (DUID) over a 5-year period (2000-2004). Venous blood or urine if available, was subjected to a broad toxicological screening analysis for cannabis, cocaine metabolite, amphetamines, opiates and the major benzodiazepines. Verification and quantitative analysis of cocaine and BZE in blood was done by gas chromatography-mass spectrometry (GC-MS) at limits of quantitation (LOQ) of 0.02 mg/L for both substances. Over the study period 26,567 blood samples were analyzed and cocaine and/or BZE were verified in 795 cases (3%). The motorists using cocaine were predominantly men (>96%) with an average age of 28.3 ± 7.1 years (±standard deviation, S.D.). The concentration of cocaine was below LOQ in 574 cases although BZE was determined at mean, median and highest concentrations of 0.19 mg/L, 0.12 mg/L and 1.3 mg/L, respectively. In 221 cases, cocaine and BZE were together in the blood samples at mean and (median) concentrations of 0.076 mg/L (0.05 mg/L) and 0.859 mg/L (0.70 mg/L), respectively. The concentrations of BZE were always higher than the parent drug, mean BZE/cocaine ratio 14.2 (median 10.9) range 1-55. Cocaine and BZE were the only psychoactive substances reported in N = 61 cases at mean (median) and highest concentrations of 0.095 (0.07) and 0.5 mg/L for cocaine and 1.01 (0.70) and 3.1 mg/L for BZE. Typical signs of drug influence noted by the arresting police officers included bloodshot and glossy eyes, agitation, difficulty in sitting still and incoherent speech. © 2007 Elsevier Ireland Ltd. All rights reserved.

  • 19.
    Jones, A Wayne
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of clinical chemistry.
    Holmgren, A
    Kugelberg, Fredrik
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology.
    Concentrations of scheduled prescription drugs in blood of impaired drivers: Considerations for interpreting the results2007In: Therapeutic Drug Monitoring, ISSN 0163-4356, E-ISSN 1536-3694, Vol. 29, no 2, p. 248-260Article in journal (Refereed)
    Abstract [en]

    We report the concentrations of scheduled prescription drugs in blood samples from people arrested in Sweden for driving under the influence of drugs (DUID). The investigation covered a 2 year period 2004 (N = 7052 cases) and 2005 (N = 7759 cases) and was prompted by recent legislation stipulating zero-concentration limits in blood for controlled substances. However, prescription drugs are exempt from the zero-limit law provided that the medication was being used in accordance with a doctor's prescription. The blood concentrations of various psychoactive substances were compared with the limits of quantitation of the analytic method used and the so-called therapeutic concentration range according to various reference books and tabulations. Diazepam [N = 1950 (26%)] and nordazepam [N = 2168 (28%)] were the therapeutic agents most frequently identified in these forensic blood samples along with other benzodiazepines such as alprazolam [N = 430 (5.6%)], flunitrazepam [N = 308 (4.0%)], and nitrazepam [N = 222 (2.9%)]. The newer hypnotics, exemplified by zolpidem [N = 148 (1.9%)] and zopiclone [N = 111 (1.5%)], were also high on the list of psychoactive substances identified. Interpreting the concentration of a prescription drug in blood in relation to whether the person had taken an overdose or was abusing the substance in question is not always easy. The age, gender, degree of obesity, and ethnicity of the person concerned, the pharmacokinetic profile of the drug, polymorphism of drug-metabolizing enzymes as well as liver and kidney function and blood hematocrit need to be considered. Among preanalytic factors, stability of the drug in blood after sampling, the type of tubes and preservatives used, the dosage form and route of administration deserve consideration. When therapeutic drug monitoring concentrations are compared with forensic toxicology results, then the plasma-to-whole blood distribution ratio of the drug also needs to be considered. In blood samples from DUID suspects, the concentrations of many commonly used sedatives and hypnotics exceeded the accepted therapeutic limits, which gives an indication of the abuse potential of these types of medications. © 2007 Lippincott Williams & Wilkins, Inc.

  • 20.
    Jones, A Wayne
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Holmgren, A
    Nationall Board of Forensic Medicine.
    Kugelberg, Fredrik
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Driving under the influence of cannabis: a 10-year study of age and gender differences in the concentrations of tetrahydrocannabinol in blood2008In: Addiction, ISSN 0965-2140, E-ISSN 1360-0443, Vol. 103, no 3, p. 452-461Article in journal (Refereed)
    Abstract [en]

    Background Delta(9)-Tetrahydrocannabinol (THC) is the major psychoactive constituent of cannabis and its various preparations Increasing use of cannabis for recreational purposes has created a problem for road-traffic safety. This paper compares age, gender and the concentrations of THC in blood of individuals apprehended for driving under the influence of drugs (DUID) in Sweden, where a zero-tolerance law operates. Measurements Specimens of blood or urine were subjected to a broad screening analysis by enzyme immunoassay methods. THC positives were verified by analysis of blood by gas chromatography-mass spectrometry (GC-MS) with a deuterium-labelled internal standard (d(3)-THC). All toxicology results were entered into a database (TOXBASE) along with the age and gender of apprehended drivers. Findings Over a 10-year period (1995-2004), between 18% and 30% of all DUID suspects had measurable amounts of THC in their blood (greater than 0.3 ng/ml) either alone or together with other drugs. The mean age [+/- standard deviation (SD)] of cannabis users was 33 +/- 9.4 years (range 15-66 years), with a strong predominance of men (94%, P less than 0.001). The frequency distribution of THC concentrations (n = 8794) was skewed markedly to the right with mean, median and highest values of 2.1 ng/ml, 1.0 ng/ml and 67 ng/ml, respectively. The THC concentration was less than 1.0 ng/ml in 43% of cases and below 2.0 ng/ml in 61% of cases. The age of offenders was not correlated with the concentration of THC in blood (r = -0.027, P greater than 0.05). THC concentrations in blood were higher when this was the only psychoactive substance present (n = 1276); mean 3.6 ng/ml, median 2.0 ng/ml compared with multi-drug users; mean 1.8 ng/ml, median 1.0 ng/ml (P less than 0.001). In cases with THC as the only drug present the concentration was less than 1.0 ng/ml in 26% and below 2.0 ng/ml in 41% of cases. The high prevalence of men, the average age and the concentrations of THC in blood were similar in users of illicit drugs (non-traffic cases). Conclusions The concentration of THC in blood at the time of driving is probably a great deal higher than at the time of sampling (30-90 minutes later) The notion of enacting science-based concentration limits of THC in blood (e.g. 3-5 ng/ml), as discussed in some quarters, would result in many individuals evading prosecution. Zero-tolerance or limit of quantitation laws are a much more pragmatic way to enforce DUID legislation

  • 21.
    Jones, A Wayne
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry.
    Holmgren, A.
    Department of Forensic Genetics and Forensic Toxicology National Board of Forensic Medicine, Linköping.
    Kugelberg, Fredrik
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology.
    Driving under the influence of central stimulant amines: Age and gender differences in concentrations of amphetamine, methamphetamine, and ecstasy in blood2008In: Journal of Studies on Alcohol and Drugs, ISSN 1937-1888, Vol. 69, no 2, p. 202-208Article in journal (Refereed)
    Abstract [en]

    Objective: A zero-tolerance law for driving under the influence of drugs (DUID) was introduced in Sweden in 1999. This change in legislation has led to a 12-fold increase in the number of blood samples sent by the police for toxicological analysis. Here we report the age and gender of offenders, along with the concentrations of amphetamine, methamphetamine, and ecstasy (3,4-methylenedioxymeth-amphetamine) in blood samples analyzed since the institution of the new legislation. Method: A forensic toxicology database (TOXBASE) was used to identify cases of DUID in which central stimulant amines were verified in blood during a 5-year period (2000-2004). Results: Amphetamine was present in 15,898 of 26,556 cases of DUID (60%) either alone or together with other licit or illicit drugs. In 6,094 cases, amphetamine was the only psychoactive substance in blood at mean (median) and highest concentrations of 1.01 mg/L (0.80 mg/L) and 11.9 mg/L, respectively. The users of amphetamine were mainly men (85% vs 15% women, p < .001), and men tended to be a few years older than the women, the mean (SD) age for men was 37 (9.2) years and for women it was 35 (8.1) years (p < .001). In 644 cases, amphetamine and methamphetamine were present in blood samples at mean (median) concentrations of 0.85 mg/L (0.60 mg/L) and 0.34 mg/L (0.20 mg/L), respectively (p < .001). The mean (median) and highest concentrations of ecstasy in 493 DUID offenders were 0.23 mg/L (0.10 mg/L) and 3.5 mg/L, respectively. The mean age of ecstasy users was 26 (7.2) years, which was about 10 years younger than those using amphetamine (p < .001). Conclusions: The high prevalence of amphetamines in blood of apprehended drivers in Sweden verifies widespread use of these stimulants as recreational drugs. The findings from this study suggest that a zero-tolerance DUID law has not deterred offenders, which suggests that more attention should be given to the underlying substance-abuse problem instead of conventional penalties such as monetary fines and/or imprisonment.

  • 22.
    Jones, A Wayne
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Pharmacology.
    Holmgren, A.
    Natl Board Forens Toxicol, Div Forens Toxicol, S-58758 Linkoping, Sweden.
    Kugelberg, Fredrik
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Natl Board Forens Toxicol, Div Forens Toxicol, S-58758 Linkoping, Sweden.
    Busardo, F. P.
    Sapienza Univ Rome, Italy.
    Relationship Between Postmortem Urine and Blood Concentrations of GHB Furnishes Useful Information to Help Interpret Drug Intoxication Deaths2018In: Journal of Analytical Toxicology, ISSN 0146-4760, E-ISSN 1945-2403, Vol. 42, no 9, p. 587-591Article in journal (Refereed)
    Abstract [en]

    This article reports the concentrations of gamma-hydroxybutyrate (GHB) in femoral blood and bladder urine in a case series of drug intoxication deaths (N = 37). GHB was determined in blood (B-GHB) and urine (U-GHB) by a GC-FID-GBL method and 30 mg/L was used as a cut-off concentration for reporting positive results. The mean (median) and range of GHB concentrations in bladder urine were 2,818 mg/L (1,900 mg/L) and 120-13,000 mg/L, respectively. These concentrations were appreciably higher than those in femoral blood, 637 mg/L (260 mg/L) and 30-9,200 mg/L, respectively. Urine/blood ratios of GHB were highly variable (mean 8.99, median 5.33 and range 0.16-29.3). GHB is rapidly metabolized and cleared from the bloodstream, whereas there is no metabolism occurring in the urinary bladder. In five autopsy cases, U-GHB was lower than B-GHB, which suggests that these individuals died before equilibration of the drug in all body fluids and tissues. In the other 32 deaths, U-GHB was higher than B-GHB, sometimes appreciably higher, which points towards a longer survival time after intake or administration of GHB. The analysis of urine extends the window of detection of GHB by several hours compared with blood samples, depending in part on when the bladder was last voided before death. Furthermore, the urinary concentration of GHB gives a hint about the concentration in blood during the time that the urine was produced in the kidney and stored in the bladder since the previous void.

  • 23.
    Jones, A Wayne
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Holmgren, Anita
    National Board for Forensic Medicine.
    Kugelberg, Fredrik
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Driving under the influence of gamma-hydroxybutyrate (GHB)2008In: FORENSIC SCIENCE MEDICINE AND PATHOLOGY, ISSN 1547-769X, Vol. 4, no 4, p. 205-211Article in journal (Refereed)
    Abstract [en]

    We used an in-house forensic toxicology database (TOXBASE) to evaluate the occurrences of gamma-hydroxybutyrate (GHB) in blood samples from people arrested in Sweden for driving under the influence of drugs (DUID) between 1998 and 2007. Age, gender, and concentrations of GHB in blood were compared and contrasted when GHB was the only drug present and when it occurred along with other drugs. GHB was determined in blood by gas chromatography (GC) after conversion to gamma-butyrolactone (GBL) and analysis of the latter with a flame ionization detector. The cut-off concentration of GHB in blood for reporting a positive result was 8 mg/l, which served as limit of quantitation. The mean and median GHB concentrations were 89 mg/l and 82 mg/l, respectively (2 1/2 and 97 1/2 percentiles 12 and 220 mg/l) in 548 arrested drivers. These individuals were predominantly men (95%) with an average age of 26 +/- 5.5 years (range 15-50 years) and women (5%) were several years older with an average age of 32 +/- 8.0 years (range 19-47). There were 102 individuals (29%) who were arrested more than once with GHB in blood (average similar to 3 times per person) and one as many as 10 times. GHB was the only psychoactive substance detected in 215 cases (39%) at mean and median blood-concentrations of 91 mg/l and 83 mg/l, respectively. These concentrations were not significantly different from poly-drug users. A weak but statistically significant correlation existed between the concentration of GHB in blood and the persons age (N = 548, r = 0.135, P less than 0.01). The signs of drug influence noted by arresting police officers included sedation, agitation, unsteady gait, slurred speech, irrational behavior, jerky body movements, dilated Pupils, and spitting. The blood concentrations reported here are probably appreciably less than at time of driving (30-90 min earlier) owing to the short elimination half-life of GHB (t1/2 = 30-40 min).

  • 24.
    Jones, A Wayne
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry.
    Holmgren, Anita
    Department of Forensic Genetics and Forensic Toxicology National Board of Forensic Medicine, Linköping.
    Kugelberg, Fredrik
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology.
    Driving under the influence of opiates: Concentration relationships between morphine, codeine, 6-acetyl morphine, and ethyl morphine in blood2008In: Journal of Analytical Toxicology, ISSN 0146-4760, E-ISSN 1945-2403, Vol. 32, no 4, p. 265-272Article in journal (Refereed)
    Abstract [en]

    Morphine and codeine are frequently identified in blood samples from impaired drivers. But whether these opiates reflect the use of prescription analgesics or abuse of the illicit drug heroin (diacetyl morphine) is not always obvious. Opiates, either alone or together with other drugs, were determined in 2573 blood specimens from impaired drivers by sensitive and specific methods of analysis. The specific metabolite of heroin 6-acetyl morphine (6-AM) was quantifiable in only 52 cases (2%) at mean, median, and highest concentrations of 0.015, 0.010, and 0.10 mg/L, respectively. The mean, median, and highest concentrations of morphine were 0.046, 0.03, and 1.13 mg/L, respectively (N = 2029). The corresponding concentrations of codeine (N = 1391) were 0.047, 0.01, and 2.40 mg/L. Ethyl morphine was identified in 63 cases at a mean concentration of 0.055 mg/L (median 0.03 mg/L). When 6-AM was present in urine (N = 324), the mean morphine/codeine ratio in blood was 7.5 (median 6.7), and this important ratio was less than unity in only two cases. This study finds compelling evidence that ∼90% of apprehended drivers in Sweden with morphine and codeine in their blood had used heroin.

  • 25.
    Jones, A Wayne
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of clinical chemistry.
    Kugelberg, Fredrik
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology.
    Letter to the Editor - Alcohol concentrations in post-mortem body fluids2006In: Human Exp Toxical, ISSN 0144-5952, Vol. 25, p. 623-624Article in journal (Other academic)
  • 26.
    Jones, A Wayne
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Division of Drug Research.
    Kugelberg, Fredrik
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Relationship between blood and urine alcohol concentrations in apprehended drivers who claimed consumption of alcohol after driving with and without supporting evidence2010In: FORENSIC SCIENCE INTERNATIONAL, ISSN 0379-0738, Vol. 194, no 1-3, p. 97-102Article in journal (Refereed)
    Abstract [en]

    For various reasons, many people suspected of driving under the influence of alcohol (DUIA) are not apprehended sitting behind the wheel, but some time after the driving. This gives them the opportunity to claim they drank alcohol after the time of driving or after they were involved in a road-traffic crash. Alleged post-offence drinking is not easy for the prosecution to disprove, which often means that the DUIA charge is dropped or the person is acquitted if the case goes to trial. The routine practice of sampling and measuring the concentration of alcohol in blood (BAC) and urine (UAC) and calculating urine/blood ratios (UAC/BAC) and the changes in UAC between two successive voids furnishes useful information to support or challenge alleged drinking after driving. We present here a retrospective case series of DUIA offenders (N = 40) in half of which there was supporting evidence of an after-drink (eye witness or police reports) and in the other half no such evidence existed apart from the suspects admission. When there was supporting evidence of an after-drink, the UAC/BAC ratio for the first void was close to or less than unity (mean 1.04, median 1.08, range 0.54-1.21) and the UAC increased by 0.21 g/L (range 0.02-0.57) between the two voids. Without any supporting evidence of post-offence drinking the mean UAC/BAC ratio was 1.46 (range 1.35-1.93) for the first void, verifying that absorption and distribution of alcohol in all body fluids and tissues was complete. In these cases, the UAC between successive voids decreased by 0.25 g/L on average (range 0.10-0.49), indicating the post-absorptive phase of the BAC curve. Long experience from investigating claims of post-offence drinking leads us to conclude that in the vast majority of cases this lacks any substance and is simply a last resort by DUIA offenders to evade justice. Unless supporting evidence exists (eye witness, police reports, etc.) of post-offence drinking the courts are encouraged to ignore this defence argument.

  • 27.
    Jones, A Wayne
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Division of Drug Research.
    Kugelberg, Fredrik
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Holmgren, A
    National Board for Forensic Medicine.
    Ahlner, Johan
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Drug poisoning deaths in Sweden show a predominance of ethanol in mono-intoxications, adverse drug-alcohol interactions and poly-drug use2011In: FORENSIC SCIENCE INTERNATIONAL, ISSN 0379-0738, Vol. 206, no 1-3, p. 43-51Article in journal (Refereed)
    Abstract [en]

    Over a 10-year period (1998-2007) all deaths in Sweden classified by forensic pathologists as fatal drug poisonings (N = 6894) were retrieved from a toxicology database (TOXBASE) belonging to the National Board of Forensic Medicine. The deaths were further classified as suicides N = 2288 (33%), undetermined N = 2260 (33%) and accidental N = 2346 (34%). The average age (+/- SD) of all victims was 49.1 +/- 15.9 years and men 47.4 +/- 15.6 years were 5-year younger than women 52.2 +/- 15.8 years (p andlt; 0.01). Most of the deceased (78%) were poly-drug users although a single drug (mono-intoxications) was found in 22% of all poisoning deaths (p andlt; 0.001). The number of drugs in blood samples varied from 1 to 12 with a median of 3-4 per case. Mono-intoxication deaths were mostly ethanol-related (N = 976) and the mean and median blood-alcohol concentration (BAC) was 3.06 g/L and 3.10 g/L, respectively. The BAC decreased as the number of additional drugs in blood increased from 2.15 g/L with one drug to 1.25 g/L with 6 or more drugs. The mean (median) concentrations of non-alcohol drugs in mono-intoxication deaths were morphine (N = 93) 0.5 mg/L (0.2 mg/L), amphetamine (N = 39) 2.0 mg/L (1.2 mg/L), dextropropoxyphene (N = 33) 3.9 mg/L (2.9 mg/L), dihydro-propiomazine (N = 32) 1.6 mg/L (1.0 mg/L) and 7-amino-flunitrazepam (N = 28), 0.4 mg/L (0.3 mg/ L). Elevated blood morphine in these poisoning deaths mostly reflected abuse of heroin as verified by finding 6-monoacetyl morphine (6-MAM) in the blood samples. When investigating drug poisoning deaths a comprehensive toxicological analysis is essential although the results do not reveal the extent of prior exposure to drugs or the development of pharmacological tolerance. The concentrations of drugs determined in post-mortem blood are one element in the case. The autopsy report, the police investigation, the findings at the scene and eye-witness statements should all be carefully considered when the cause and manner of death are determined.

  • 28.
    Jones, A Wayne
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Division of Drug Research.
    Kugelberg, Fredrik
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Holmgren, Anita
    National Board for Forensic Medicine.
    Ahlner, Johan
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Five-year update on the occurrence of alcohol and other drugs in blood samples from drivers killed in road-traffic crashes in Sweden2009In: Forensic Science International, ISSN 0379-0738, E-ISSN 1872-6283, Vol. 186, no 01-Mar, p. 56-62Article in journal (Refereed)
    Abstract [en]

    According to statistics provided by the Swedish National Road Administration (Vagverket). a total of 1403 drivers were killed in road-traffic crashes in Sweden between 2003 and 2007. Forensic autopsies were performed in similar to 97% of all deaths and specimens of blood and urine were sent for toxicological analysis. In 60% of cases (N = 835) the toxicology results were negative and 83% of these victims were men. The blood-alcohol concentration (BAC) was above the legal limit for driving (greater than0.2 g/L) in 22% of cases (N = 315) at mean, median and highest concentrations of 1.7 g/L, 1.7 g/L and 4.9 g/L, respectively. The proportions of male to female drivers with BAC greater than 0.2 g/L were 93% vs 7% compared with 83% vs 17% for those with drugs other than alcohol in blood. Drivers with a punishable BAC were over-represented in single vehicle crashes compared with multiple vehicle crashes (67% vs 33%). The opposite held for drivers who had taken a prescription drug (39% vs 61%) and also for drug-negative cases (31% vs 69%). Drugs other than alcohol were identified in 253 cases (18%); illicit drugs only in 39 cases (2.8%), both licit and illicit in 28 cases (2.0%) and in 186 cases (13.3%) one or more therapeutic drugs were present. Amphetamine was the most common illicit drug identified at mean, median and highest concentrations of 1.5 mg/L, 1.1 mg/L and 5.0 mg/L, respectively (N = 39). Blood specimens contained a wide spectrum of pharmaceutical products (mean 2.4 drugs/person), comprising sedative-hypno tics (N = 93), opiates/opioids (N = 69) as well non-scheduled substances, such as paracetamol (N = 78) and antidepressants (N = 93). The concentrations of these substances in blood were mostly in the therapeutic range. Despite an appreciable increase (12-fold) in number of arrests made by the police for drug-impaired driving after a zero-tolerance law was introduced (July 1999), alcohol still remains the psychoactive substance most frequently identified in the blood of drivers killed in road-traffic crashes. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

  • 29.
    Jones, A Wayne
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry.
    Kugelberg, Fredrik
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology.
    Holmgren, Anita
    Department of Forensic Genetics and Forensic Toxicology National Board of Forensic Medicine, Linköping.
    Ahlner, Johan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology.
    Occurrence of ethanol and other drugs in blood and urine specimens from female victims of alleged sexual assault2008In: Forensic Science International, ISSN 0379-0738, E-ISSN 1872-6283, Vol. 181, no 1-3, p. 40-46Article in journal (Refereed)
    Abstract [en]

    Results of toxicological analysis of blood and urine specimens from 1806 female victims of alleged non-consensual sexual activity are reported. After making contact with the police authorities, the victims were examined by a physician for injuries and biological specimens were taken for forensic toxicology and other purposes (e.g. DNA). Urine if available or otherwise on an aliquot of blood after protein precipitation was screened for the presence of drugs by enzyme immunoassay methods (EMIT/CEDIA). All positive results from screening were verified by more specific methods, involving isotope dilution gas chromatography-mass spectrometry (GC-MS) for illicit drugs. A large number of prescription drugs were analyzed in blood by capillary column gas chromatography with a nitrogen-phosphorous (N-P) detector. Ethanol was determined in blood and urine by headspace gas chromatography and concentrations less than 0.1 g/L were reported as negative. The number of reported cases of alleged sexual assault was highest during the warmer summer months and the mean age of victims was 24 years (median 20 years), with ∼60% being between 15 and 25 years. In 559 cases (31%) ethanol and drugs were negative. In 772 cases (43% of total) ethanol was the only drug identified in blood or urine. In 215 cases (12%) ethanol occurred together with at least one other drug. The mean, median and highest concentrations of ethanol in blood (N = 806) were 1.24 g/L, 1.19 g/L and 3.7 g/L, respectively. The age of victims and their blood-alcohol concentration (BAC) were positively correlated (r = 0.365, p < 0.001). Because BAC decreases at a rate of 0.10-0.25 g/(L h), owing to metabolism the concentration in blood at time of sampling is often appreciably less than when the crime was committed several hours earlier. Licit or illicit drugs were identified in blood or urine in N = 262 cases (15%). Amphetamine and tetrahydrocannabinol were the most common illicit drugs at mean (median) concentrations in blood of 0.22 mg/L (0.1 mg/L) and 0.0012 mg/L (0.0006 mg/L), respectively. Among prescription drugs, sedative-hypnotics such as diazepam and zopiclone were common findings along with SSRI antidepressants and various opiate analgesics. Interpreting the analytical results in terms of voluntary vs. surreptitious administration of drugs and the degree of incapacitation in the victim as well as ability to give informed consent for sexual activity is fraught with difficulties. © 2008 Elsevier Ireland Ltd. All rights reserved.

  • 30.
    Karlsson, Louise
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences.
    Andersson, Mikael
    National Board Forens Med, Department Forens Genet and Forens Toxicol, SE-58758 Linkoping, Sweden.
    Kronstrand, Robert
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Health Sciences.
    Kugelberg, Fredrik
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences.
    Mephedrone, Methylone and 3,4-Methylenedioxypyrovalerone (MDPV) Induce Conditioned Place Preference in Mice2014In: Basic & Clinical Pharmacology & Toxicology, ISSN 1742-7835, E-ISSN 1742-7843, Vol. 115, no 5, p. 411-416Article in journal (Refereed)
    Abstract [en]

    During the last decade, there has been a worldwide increase in popularity and abuse of synthetic cathinones. Common ingredients of the so-called bath salts include mephedrone, methylone and 3,4-methylenedioxypyrovalerone (MDPV). Relatively little information about the pharmacology and addiction potential of these drugs is available. We used the conditioned place preference (CPP) paradigm to explore the reinforcing effects of three different synthetic cathinones. The primary aim of this study was to investigate whether mephedrone, methylone and MDPV induce CPP in mice. The secondary aims were to investigate a possible dose-response CPP and whether the synthetic cathinones induce higher CPP than amphetamine at equal dose. C57BL/6 mice were conditioned to mephedrone, methylone, MDPV and amphetamine at doses of 0.5, 2, 5, 10 or 20mg/kg (i.p.). During the conditioning, the mice received two training sessions per day for 4days. All four tested drugs showed a significant place preference compared with controls. Mice conditioned with MDPV (5 and 10mg/kg) displayed a greater preference score compared to mice conditioned with amphetamine (5 and 10mg/kg). Our findings show that mephedrone, methylone and MDPV produce CPP equal or higher than amphetamine strongly suggesting addictive properties. Given the public health concern of abuse, future pharmacological studies are necessary to fully understand the effects of these drugs.

  • 31.
    Karlsson, Louise
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Carlsson, Björn
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Pharmacology.
    Hiemke, Christoph
    Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg-University of Mainz, Mainz, Germany.
    Ahlner, Johan
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Bengtsson, Finn
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Pharmacology.
    Schmitt, Ulrich
    Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg-University of Mainz, Mainz, Germany.
    Kugelberg, Fredrik C.
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Altered brain concentrations of citalopram and escitalopram in P-glycoprotein deficient mice after acute and chronic treatment2013In: European Neuropsychopharmacology, ISSN 0924-977X, E-ISSN 1873-7862, Vol. 23, no 11, p. 1636-1644Article in journal (Refereed)
    Abstract [en]

    Background: According to both in vitro and in vivo data P-glycoprotein (P-gp) may restrict the uptake of several antidepressants into the brain, thus contributing to the poor success rate of current antidepressant therapies. The therapeutic activity of citalopram resides in the Senantiomer, whereas the R-enantiomer is practically devoid of serotonin reuptake potency. To date, no in vivo data are available that address whether the enantiomers of citalopram and its metabolites are substrates of P-gp.

    Methods: P-gp knockout (abcb1ab (-/-)) and wild-type (abcb1ab (+/+)) mice underwent acute (single-dose) and chronic (two daily doses for 10 days) treatment with citalopram (10 mg/kg) or escitalopram (5 mg/kg). Serum and brain samples were collected 1-6 h after the first or last i.p. injection for subsequent drug analysis by an enantioselective HPLC method. Results: In brain, 3-fold higher concentrations of S- and R-citalopram, and its metabolites, were found in abcb1ab (-/-) mice than in abcb1ab (+/+) mice after both acute and chronic citalopram treatments. After escitalopram treatment, the S-citalopram brain concentration was 3-5 times higher in the knockout mice than in controls.

    Conclusions: The results provide novel evidence that the enantiomers of citalopram are substrates of P-gp. Possible clinical and toxicological implications of this finding need to be further elucidated.

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  • 32.
    Karlsson, Louise
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Green, Henrik
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Zackrisson, Anna Lena
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Bengtsson, Finn
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Jakobsen Falk, I
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Carlsson, Björn
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Pharmacology.
    Ahlner, Johan
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Kugelberg, Fredrik
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    ABCB1 gene polymorphisms are associated with fatal intoxications involving venlafaxine but not citalopram2013In: International journal of legal medicine, ISSN 0937-9827, E-ISSN 1437-1596, Vol. 127, no 3, p. 579-586Article in journal (Refereed)
    Abstract [en]

    P-glycoprotein (P-gp), encoded by the ABCB1/MDR1 gene, is a drug transporter at the blood–brain barrier. Several polymorphisms in the ABCB1 gene are known to affect the activity and/or expression of P-gp, thereby influencing the treatment response and toxicity of P-gp substrates like citalopram and venlafaxine. In this study, we aimed to investigate the frequency of ABCB1 genotypes in forensic autopsy cases involving these two antidepressants. Further, the distribution of ABCB1 genotypes in deaths related to intoxication was compared to cases not associated to drug intoxication. The study included 228 forensic autopsy cases with different causes and manners of deaths. The ABCB1 single nucleotide polymorphisms (SNPs) G1199A, C1236T, C3435T and G2677T/A for these individuals were determined. The SNPs C1236T and C3435T in venlafaxine-positive cases were significantly different between the intoxication cases and non-intoxications. This was not seen for cases involving citalopram, indicating that the effect of genetic variants might be substrate specific. This novel finding should, however, be confirmed in future studies with larger number of cases.

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  • 33.
    Karlsson, Louise
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Green, Henrik
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Zackrisson, Anna Lena
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Bengtsson, Finn
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Diagnostics, Department of Clinical Pharmacology.
    Jakobsen Falk, Ingrid
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Carlsson, Björn
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Diagnostics, Department of Clinical Pharmacology.
    Ahlner, Johan
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Kugelberg, Fredrik C.
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    ABCB1 gene polymorphisms in forensic autopsy cases positive for citalopram and venlafaxineManuscript (preprint) (Other academic)
    Abstract [en]

    P-glycoprotein (P-gp), encoded by the ABCB1/MDR1 gene, is a drug transporter expressed on e.g. the endothelial cells of the blood-brain barrier which regulates the efflux of many drugs. Several polymorphisms in the ABCB1 gene are known to affect the activity and/or expression of P-gp, thereby influencing the treatment response and toxicity of P-gp substrates. It has previously been shown that the antidepressant drugs citalopram and venlafaxine are actively transported out of the brain by P-gp using a mouse model. In the present study we aimed to investigate the frequency of ABCB1 genotypes in forensic autopsy cases positive for these two antidepressants. Further, the distribution of ABCB1 genotypes in deaths related to intoxication was compared to cases not associated to drug intoxication. The present study included 228 forensic autopsy cases positive for venlafaxine and citalopram with different causes of deaths. The ABCB1 single nucleotide polymorphisms (SNPs) G1199A, C1236T, C3435T and G2677T/A for these individuals were determined by Pyrosequencing. The SNPs C1236T, G2677T and C3435T in venlafaxine positive cases were significantly different between the intoxication cases and non-intoxications. The latter novel finding should, however, be confirmed in future studies with larger number of cases.

  • 34.
    Karlsson, Louise
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Hiemke, Christoph
    Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg-University of Mainz, Germany .
    Carlsson, Björn
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Diagnostics, Department of Clinical Pharmacology.
    Josefsson, Martin
    Department of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Artillerigatan 12, Sweden.
    Ahlner, Johan
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Bengtsson, Finn
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Diagnostics, Department of Clinical Pharmacology.
    Schmitt, Ulrich
    Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg-University of Mainz, Germany .
    Kugelberg, Fredrik C
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Effects on enantiomeric drug disposition and open-field behavior after chronic treatment with venlafaxine in the P-glycoprotein knockout mice model2011In: Psychopharmacology, ISSN 0033-3158, E-ISSN 1432-2072, Vol. 215, no 2, p. 367-377Article in journal (Refereed)
    Abstract [en]

    Our results show that P-gp at the blood-brain barrier plays an important role in limiting brain entry of the enantiomers of venlafaxine and its metabolites after chronic dosing. Taken together, the present pharmacokinetic and pharmacodynamic findings offer the possibility that the expression of P-gp in patients may be a contributing factor for limited treatment response.

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  • 35.
    Karlsson, Louise
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Kingbäck, Maria
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Josefsson, M
    Rättsmedicinalverket, Rättskemi.
    Carlsson, Björn
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Diagnostics, Department of Clinical Pharmacology.
    Ahlner, Johan
    Linköping University, Department of Medical and Health Sciences, Forensic Science and Toxicology . Linköping University, Faculty of Health Sciences.
    Schmidt, U
    Tyskland.
    Kugelberg, Fredrik
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Hiemke, Ch
    Tyskland.
    Bengtsson, Finn
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Diagnostics, Department of Clinical Pharmacology.
    Penetration of the enantiomers of venlafaxine and its metabolites into the brain in mice lacking P-glycoprotein (mdr1ab)2008Conference paper (Other academic)
  • 36.
    Karlsson, Louise
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Schmitt, Ulrich
    Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg-University of Mainz, Mainz, Germany.
    Josefsson, Martin
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Carlsson, Björn
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Pharmacology.
    Ahlner, Johan
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Bengtsson, Finn
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Pharmacology.
    Kugelberg, Fredrik C
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Hiemke, Christoph
    Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg-University of Mainz, Mainz, Germany.
    Blood-brain barrier penetration of the enantiomers of venlafaxine and its metabolites in mice lacking P-glycoprotein2010In: European Neuropsychopharmacology, ISSN 0924-977X, E-ISSN 1873-7862, Vol. 20, no 9, p. 632-640Article in journal (Refereed)
    Abstract [en]

    According to in vitro studies the enantiomers of venlafaxine display different degrees of serotonin and noradrenaline reuptake inhibition. Therefore, clarification of the enantiomeric drug distribution between serum and brain is highly warranted. To elucidate if P-glycoprotein (P-gp) in a stereoselective manner transports venlafaxine and its metabolites out of the brain we used abcb1ab double-knockout mice that do not express P-gp. A single dose of racemic venlafaxine (10 mg/kg bw) was intraperitoneally injected to knockout (-/-) and wildtype (+/+) mice. Serum and brain samples were collected 1, 3, 6 and 9 h following drug administration for analysis by LC/MS/MS. One to six hours post-dose, the brain concentrations of venlafaxine, O-desmethylvenlafaxine and N-desmethylvenlafaxine were 2-3, 2-6 and 3-12 times higher in abcb1ab (-/-) mice compared to abcb1ab (+/+) mice, respectively. No major differences in the serum and brain disposition of the S- and R-enantiomers of venlafaxine and its metabolites were found between the groups. We conclude that P-gp decreases the penetration of the S- and R-enantiomers of venlafaxine and its major metabolites into the brain. No evidence of a stereoselective P-gp mediated transport of these substances was observed.

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  • 37.
    Karlsson, Louise
    et al.
    Region Östergötland, Center for Diagnostics, Department of Clinical Pharmacology. Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences.
    Zackrisson, Anna Lena
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Department of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Linköping, Sweden.
    Josefsson, M
    Department of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Linköping, Sweden; 3Department of Physics, Chemistry and Biology, Linköping University, Linköping, Sweden.
    Carlsson, Björn
    Region Östergötland, Center for Diagnostics, Department of Clinical Pharmacology. Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    Green, Henrik
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Department of Forensic Genetics andForensic Toxicology, National Board of Forensic Medicine, Linköping, Sweden.
    Kugelberg, Fredrik C
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Department of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Linköping, Sweden.
    Influence of CYP2D6 and CYP2C19 genotypes on venlafaxine metabolic ratios and stereoselective metabolism in forensic autopsy cases.2015In: The Pharmacogenomics Journal, ISSN 1470-269X, E-ISSN 1473-1150, Vol. 15, no 2, p. 165-71Article in journal (Refereed)
    Abstract [en]

    We investigated whether polymorphisms in the CYP2D6 and CYP2C19 genes influence the metabolic ratios and enantiomeric S/R ratios of venlafaxine (VEN) and its metabolites O-desmethylvenlafaxine (ODV), N-desmethylvenlafaxine (NDV) and N,O-didesmethylvenlafaxine (DDV) in blood from forensic autopsy cases. In all, 94 postmortem cases found positive for VEN during toxicological screening were included. The CYP2D6 genotype was shown to significantly influence the ODV/VEN (P=0.003), DDV/NDV (P=0.010) and DDV/ODV (P=0.034) ratios. The DDV/ODV (P=0.013) and DDV/VEN (P=0.021) ratios were significantly influenced by the CYP2C19 genotype. The S/R ratios of VEN were significantly influenced by both CYP2D6 and CYP2C19 genotypes. CYP2D6 poor metabolizers (PMs) had lower S/R VEN ratios and CYP2C19 PMs had high S/R ratios of VEN in comparison. Our results show that the CYP2D6 genotype influences the O-demethylation whereas CYP2C19 influences the N-demethylation of VEN and its metabolites. In addition, we show a stereoselective metabolism where CYP2D6 favours the R-enantiomer whereas CYP2C19 favours the S-enantiomer.

  • 38.
    Kingbäck, Maria
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Carlsson, Björn
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Pharmacology.
    Ahlner, Johan
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Bengtsson, Finn
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Pharmacology.
    Kugelberg, Fredrik
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Cytochrome P450-Dependent Disposition of the Enantiomers of Citalopram and Its Metabolites: In Vivo Studies in Sprague-Dawley and Dark Agouti Rats2011In: Chirality, ISSN 0899-0042, E-ISSN 1520-636X, Vol. 23, no 2, p. 172-177Article in journal (Refereed)
    Abstract [en]

    The female Sprague-Dawley (SD) and Dark Agouti (DA) rats are considered the animal counterparts of the human extensive and poor metabolizer cytochrome P450 (CYP) 2D6 phenotypes, respectively. The aim of this work was to study possible rat strain differences in the steady-state pharmacokinetics of the (+)-(S)- and (-)-(R)-enantiomers of citalopram and its demethylated metabolites. A chronic drug treatment regimen (15 mg/kg daily) was implemented for 13 days in separate groups of SD (n 5 9) and DA (n 5 9) rats by using osmotic pumps. The concentrations of citalopram and two major metabolites in serum and two brain regions were analyzed by an enantioselective high-performance liquid chromatography assay. Higher serum and brain levels of citalopram and demethylcitalopram, but lower levels of didemethylcitalopram, were observed in DA rats when compared with SD rats. The enantiomeric (S/R) concentrations ratios of citalopram were lower in the DA rats when compared with the SD rats (0.53 +/- 0.05 vs. 0.80 +/- 0.03, P andlt; 0.001), indicating a possibly decreased capacity in the metabolism of the (-)-(R)-enantiomer in the DA rats. This study shows that CYP2D deficiency results in steady-state pharmacokinetic differences of the enantiomers of citalopram and its metabolites.

  • 39.
    Kingbäck, Maria
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Josefsson, M
    Linköping University, Department of Medical and Health Sciences, Pharmacology.
    Kugelberg, Fredrik
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Bengtsson, Finn
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Diagnostics, Department of Clinical Pharmacology.
    Ahlner, Johan
    Linköping University, Department of Medical and Health Sciences, Forensic Science and Toxicology . Linköping University, Faculty of Health Sciences.
    Carlsson, Björn
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Diagnostics, Department of Clinical Pharmacology.
    Stereoselective analysis of venlafaxine and its three major metabolites by liquid chromatography with electrospray tandem mass spectrometry2008Conference paper (Other academic)
  • 40.
    Kingbäck, Maria
    et al.
    Linköping University, Department of Medicine and Health Sciences, Clinical Pharmacology . Linköping University, Faculty of Health Sciences.
    Josefsson, Martin
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Karlsson, Louise
    Linköping University, Department of Medicine and Health Sciences, Clinical Pharmacology . Linköping University, Faculty of Health Sciences.
    Ahlner, Johan
    Linköping University, Department of Medicine and Health Sciences, Clinical Pharmacology . Linköping University, Faculty of Health Sciences.
    Bengtsson, Finn
    Linköping University, Department of Medicine and Health Sciences, Clinical Pharmacology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Pharmacology.
    Kugelberg, Fredrik C
    Linköping University, Department of Medicine and Health Sciences, Clinical Pharmacology . Linköping University, Faculty of Health Sciences.
    Carlsson, Björn
    Linköping University, Department of Medicine and Health Sciences, Clinical Pharmacology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Pharmacology.
    Stereoselective determination of venlafaxine and its three demethylated metabolites in human plasma and whole blood by liquid chromatography with electrospray tandem mass spectrometric detection and solid phase extraction2010In: Journal of Pharmaceutical and Biomedical Analysis, ISSN 0731-7085, E-ISSN 1873-264X, Vol. 53, no 3, p. 583-590Article in journal (Refereed)
    Abstract [en]

    A stereoselective method is described for simultaneous determination of the S- and R-enantiomers of venlafaxine and its three demethylated metabolites in human plasma and whole blood samples. This validated method involved LC/MS/MS with positive electrospray ionization and solid phase extraction. Chromatographic separation was performed on a 250 mm x 2.1mm Chirobiotic V column with a total run time of 35 min. In plasma, calibration curves were in the range of 1-1000 nM for the S- and R-enantiomers of venlafaxine and O-desmethylvenlafaxine, and 0.5-500 nM for N-desmethylvenlafaxine and N,O-didesmethylvenlafaxine. In whole blood the corresponding concentrations were 10-4000 and 5-2000 nM, respectively. The intra-day precision was <6.3% and the inter-day precision was <9.9% for plasma and <15% and <19% for whole blood. LLOQ ranged between 0.25 and 0.5 nM. No ion suppression/enhancement or other matrix effects were observed. The method was successfully applied for determination of venlafaxine and its metabolites in plasma from patients and whole blood samples from forensic autopsy cases.

  • 41.
    Kingbäck, Maria
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Karlsson, Louise
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Carlsson, Björn
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Pharmacology.
    Josefsson, Martin
    Department of Forensic Genetics and Forensic Toxicology,National Board of Forensic Medicine.
    Ahlner, Johan
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Bengtsson, Finn
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Pharmacology.
    Kugelberg, Fredrik
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Pharmacokinetic Differences in the Disposition of the Enantiomers of Venlafaxine and Its Metabolites in Sprague-Dawley and Dark Agouti RatsManuscript (preprint) (Other academic)
    Abstract [en]

    Venlafaxine is a frequently prescribed racemic antidepressant drug worldwide, consisting of two enantiomers that exhibit similar but not identical biological activity profiles. Venlafaxine is extensively metabolised by the cytochrome P450 (CYP) system. CYP2D6 is involved in the formation of O-desmethylvenlafaxine (Odm-venlafaxine) and CYP3A4 in the formation of Ndesmethylvenlafaxine (Ndm-venlafaxine). The female Dark Agouti and Sprague-Dawley rats are considered the animal counterparts of the human CYP2D6 poor and extensive metaboliser phenotypes, respectively. Since CYP2D6 seems to play a major role in the metabolism of venlafaxine, the aim of this work was to study possible differences in the pharmacokinetics of the enantiomers of venlafaxine and its metabolites in these two different rat strains. Following single administration of racemic venlafaxine (15 mg/kg) serum and brain samples were collected and the concentrations of the enantiomers of venlafaxine and its three major metabolites were determined using an enantioselective LC/MS/MS method. Higher serum and brain concentrations of venlafaxine were observed in Dark Agouti rats as compared to Sprague-Dawley rats (p=0.0002). In relation to the Odm-venlafaxine concentration, the Ndmvenlafaxine concentrations were much higher in Dark Agouti rats than in Sprague-Dawley rats (p<0.0001). The enantiomeric (S/R) venlafaxine ratios were almost two times higher in Dark Agouti rats than in Sprague-Dawley rats, which was observed in both serum and brain (p<0.0001). The present results give hints for possible differences in the pharmacokinetics of venlafaxine in human extensive and poor metaboliser CYP2D6 phenotype subjects.

  • 42.
    Kingbäck, Maria
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Karlsson, Louise
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Zackrisson, Anna-Lena
    National Board of Forensic Medicine, Linköping, Sweden.
    Josefsson, Martin
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Health Sciences. National Board of Forensic Medicine, Linköping, Sweden.
    Carlsson, Björn
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Pharmacology.
    Bengtsson, Finn
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Pharmacology.
    Ahlner, Johan
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Kugelberg, Fredrik C
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Influence of CYP2D6 genotype on the disposition of the enantiomers of venlafaxine and its major metabolites in postmortem femoral blood2012In: Forensic Science International, ISSN 0379-0738, E-ISSN 1872-6283, Vol. 214, no 1-3, p. 124-134Article in journal (Refereed)
    Abstract [en]

    Venlafaxine (VEN) is an antidepressant drug mainly metabolized by the cytochrome P450 (CYP) enzyme CYP2D6 to the active metabolite O-desmethylvenlafaxine (ODV). VEN is also metabolized to N-desmetylvenlafaxine (NDV) via CYP3A4. ODV and NDV are further metabolized to N,O-didesmethylvenlafaxine (DDV). VEN is a racemic mixture of the S- and R-enantiomers and these have in vitro displayed different degrees of serotonin and noradrenaline reuptake inhibition. The aim of the study was to investigate if an enantioselective analysis of VEN and its metabolites, in combination with genotyping for CYP2D6, could assist in the interpretation of forensic toxicological results in cases with different causes of deaths. Concentrations of the enantiomers of VEN and metabolites were determined in femoral blood obtained from 56 autopsy cases with different causes of death. The drug analysis was done by liquid chromatography tandem mass spectrometry (LC/MS/MS) and the CYP2D6 genotyping by PCR and pyrosequencing. The mean (median) enantiomeric S/R ratios of VEN, ODV, NDV and DDV were 0.99 (0.91), 2.17 (0.93), 0.92 (0.86) and 1.08 (1.03), respectively. However, a substantial variation in the relationship between the S- and R-enantiomers of VEN and metabolites was evident (S/R ratios ranging from 0.23 to 17.6). In six cases, a low S/R VEN ratio (mean 0.5) was associated with a high S/R ODV ratio (mean 11.9). Genotyping showed that these individuals carried two inactive CYP2D6 genes indicating a poor metabolizer phenotype. From these data we conclude that enantioselective analysis of VEN and ODV can predict if a person is a poor metabolizer genotype/phenotype for CYP2D6. Knowledge of the relationship between the S- and R-enantiomers of this antidepressant drug and its active metabolite is also important since the enantiomers display different pharmacodynamic profiles.

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  • 43.
    Kronstrand, Christoffer
    et al.
    Natl Board Forens Med, Dept Forens Genet and Forens Toxicol, Linkoping, Sweden.
    Nilsson, Gunnel
    Natl Board Forens Med, Dept Forens Genet and Forens Toxicol, Linkoping, Sweden.
    Cherma, Maria D.
    Natl Board Forens Med, Dept Forens Genet and Forens Toxicol, Linkoping, Sweden.
    Ahlner, Johan
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Natl Board Forens Med, Dept Forens Genet and Forens Toxicol, Linkoping, Sweden.
    Kugelberg, Fredrik
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Natl Board Forens Med, Dept Forens Genet and Forens Toxicol, Linkoping, Sweden.
    Kronstrand, Robert
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Natl Board Forens Med, Dept Forens Genet and Forens Toxicol, Linkoping, Sweden.
    Evaluating the hip-flask defence in subjects with alcohol on board: An experimental study2019In: Forensic Science International, ISSN 0379-0738, E-ISSN 1872-6283, Vol. 294, p. 189-195Article in journal (Refereed)
    Abstract [en]

    Driving under the influence of alcohol is a major problem for traffic-safety and a popular defence argument is alleged consumption after driving, commonly referred to as the hip-flask defence. Forensic toxicologists are often called as expert witnesses in drinking and driving cases where the suspect has claimed the hip-flask defence, to assess the credibility of the explanation. Several approaches to help the expert have been introduced but the scientific data used to support or challenge this is solely based on data from controlled single doses of ethanol administered during a short time and in abstinent subjects. In reality, we believe that even in drinking after driving cases, the subject many times has alcohol on board at time of the hip-flask drink. This questions the applicability of the data used as basis to investigate the hip-flask defence. To fill this knowledge gap, we aimed to investigate how blood and urine ethanol kinetics vary after an initial drinking session of beer and then a subsequent hip-flask drink of three different doses of whiskey. Fifteen subjects participated in the study and each provided 10 urine samples and 17 blood samples over 7 h. The initial drink was 0.51 g ethanol/kg and the second was either 0.25, 0.51, or 0.85 g/kg. Our data suggested that the difference between the ethanol concentrations in two consecutive urine samples is a more sensitive parameter than the ratio between urine and blood alcohol to detect a recent intake when ethanol from previous intakes are already present in the body. Twelve subjects presented results that fully supported a recent intake using the criteria developed from a single intake of ethanol. Three subjects showed unexpected results that did not fully support a recent intake. We conclude that data from one blood sample and two urine samples provide good evidence for investigating the hip-flask defence even if alcohol was on board at the time of the hip-flask drink. (C) 2018 Elsevier B.V. All rights reserved.

  • 44.
    Kronstrand, Robert
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences. National Board of Forensic Medicine, Linköping, Sweden.
    Thelander, G.
    National Board of Forensic Medicine, Linköping, Sweden.
    Lindstedt, D.
    National Board of Forensic Medicine, Linköping, Sweden.
    Roman, M.
    National Board of Forensic Medicine, Linköping, Sweden.
    Kugelberg, Fredrik
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences. National Board of Forensic Medicine, Linköping, Sweden.
    Fatal intoxications associated with the designer opioid AH-79212014In: Journal of Analytical Toxicology, ISSN 0146-4760, E-ISSN 1945-2403, Vol. 38, no 8, p. 599-604Article in journal (Refereed)
    Abstract [en]

    AH-7921 (3,4-dichloro-N-[(1-dimethylamino) cyclohexylmethyl] benzamide) is a designer opioid with similar to 80% of morphines m-agonist activity. Over a 6-month period, we encountered nine deaths where AH-7921 was involved and detected in blood from the deceased. Shortly after the last death, on August 1 2013, AH-7921 was scheduled as a narcotic and largely disappeared from the illicit market in Sweden. AH-7921 was measured by a selective liquid chromatography- MS-MS method and the concentrations of AH-7921 ranged from 0.03 to 0.99 mu g/g blood. Six of our cases had other drugs of abuse on board and most had other medications such as benzodiazepines, antidepressants and analgesics. However, the other medicinal drugs encountered were present in postmortem therapeutic concentrations and unlikely to have contributed to death. In addition to the parent compound, we identified six possible metabolites where two N-demethylated dominated and four mono-hydroxylated were found in trace amounts in the blood. In conclusion, deaths with AH-7921 seem to occur both at low and high concentrations, probably a result of different tolerance to the drug. Hence, it is reasonable to assume that no sharp dividing line exists between lethal and non-lethal concentrations. Further, poly-drug use did not seem to be a major contributing factor for the fatal outcome.

  • 45.
    Kugelberg, Fredrik
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology.
    Alkass, Kanar
    Kingbäck, Maria
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology.
    Carlsson, Björn
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Pharmacology.
    Influence of blood loss on the pharmacokinetics of citalopram2006In: Forensic Science International, ISSN 0379-0738, E-ISSN 1872-6283, Vol. 161, no 2-3, p. 163-168Article in journal (Refereed)
    Abstract [en]

    Extended blood loss results in several compensatory physiological mechanisms, including transfer of extravascular fluid into the blood circulation. If drugs are present in the body, this fluid exchange may imply that blood drug concentrations found in a trauma victim may differ from the concentrations present at the time of the trauma. To address this issue, an animal model was used to investigate the influence of blood loss on pre-existing levels of the antidepressant drug citalopram and its demethylated metabolites. Rats were administered citalopram either acutely (40 mg/kg, orally) or chronically (20 mg/kg daily, subcutaneously) for 6 days using osmotic pumps. In the experimental rats, blood loss was accomplished by withdrawing 0.8 mL blood at 10 min intervals during 70 min. In the control rats, blood was withdrawn at 0 and 70 min only. Blood, brain and lung drug concentrations were analyzed with an enantioselective HPLC method. In the chronically treated rats, the ratios between final and initial citalopram concentrations were 1.08 ± 0.15 and 1.01 ± 0.09 in the experimental rats and controls, respectively, indicating no major effect of blood loss. In contrast, acute oral administration resulted in increased ratios in the exsanguinated rats as compared to controls (1.84 ± 0.50 versus 0.73 ± 0.07, p = 0.0495). In conclusion, the observation of increased blood drug levels in the acute oral rats indicates that absorption of fluid from the gastrointestinal tract may be important in the intravascular refill. Further, in the interpretation of post-mortem blood levels of drugs, these physiological mechanisms should be taken into account. © 2006 Elsevier Ireland Ltd. All rights reserved.

  • 46.
    Kugelberg, Fredrik
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology.
    Apelqvist, G
    Klinisk farmakologi Lund.
    Wikell, C
    Klinisk farmakologi Lund.
    Bengtsson, Finn
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Pharmacology.
    Open-field behavioural alterations in liver-impaired and sham-operated rats after acute exposure to the antidepressant venlafaxine2005In: Basic & Clinical Pharmacology & Toxicology, ISSN 1742-7835, E-ISSN 1742-7843, Vol. 97, no 3, p. 155-161Article in journal (Refereed)
    Abstract [en]

    Patients with chronic liver impairment often display symptoms of affective psychiatric nature where the choice for antidepressant treatment is rational. Since caution is recommended when these drugs are used in such patients, a dose reduction is usually performed. We have previously reported that a dose reduction to liver-impaired portacaval shunted rats has resulted in similar brain concentrations of venlafaxine as compared to sham-operated control rats that received a two times higher dose. The main aim of the present study was therefore to investigate if this "normalisation" in pharma-cokinetics of the portacaval-shunted rats also was true for the pharmacodynamic response in terms of drug effect on spontaneous open-field behaviour. Thus, portacaval-shunted rats received a single reduced dose (5 mg/kg) of venlafaxine or saline, whereas sham-operated rats received either 10 mg/kg or saline. Thereafter, central and peripheral arena locomotor and rearing activities were recorded during 60 min. The venlafaxine-treated portacaval-shunted and sham rats displayed reduced and unchanged overall behavioural activities compared with corresponding controls, respectively. However, the ratios between centrally and peripherally performed behavioural activities were higher in the venlafaxine-treated sham rats, indicating an increase in central arena activity as compared to the sham-saline and portacaval-shunted rats. The present study indicates that, despite a 50% dose reduction, caution still is necessary when antidepressants are used in liver insufficient subjects. This study also shows the importance of detailed open-field behavioural studies in which both central and peripheral activities are recorded for measurement of open-field behavioural drug effects. © Basic & Clinical Pharmacology & Toxicology 2005.

  • 47.
    Kugelberg, Fredrik
    et al.
    Linköping University, Department of Medicine and Care, Clinical Pharmacology. Linköping University, Department of Neuroscience and Locomotion, Psychiatry.
    Apelqvist, Gustav
    Department of Clinical Pharmacology, Institute of Laboratory Medicine, Lund University, Lund, Sweden.
    Carlsson, Björn
    Linköping University, Department of Medicine and Care, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Ahlner, Johan
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Bengtsson, Finn
    Linköping University, Department of Medicine and Care, Clinical Pharmacology. Linköping University, Department of Neuroscience and Locomotion, Psychiatry. Linköping University, Faculty of Health Sciences.
    In vivo steady-state pharmacokinetic outcome following clinical and toxic doses of racemic citalopram to rats2001In: British Journal of Pharmacology, ISSN 0007-1188, E-ISSN 1476-5381, Vol. 132, no 8, p. 1683-1690Article in journal (Refereed)
    Abstract [en]
    • The thymoleptic drug citalopram (CIT) belongs to the selective serotonin reuptake inhibitors (SSRIs) and is today extensively used in psychiatry. Further clarification of the enantiomer-selective distribution of racemic CIT in both clinical and toxic doses is highly warranted.

    • By a steady-state in vivo paradigm, rats underwent chronic systemic exposure for 10 days by using osmotic pumps and the total as well as the individual distributions of the S- and R-enantiomers of CIT, and its metabolites in serum and two different brain regions, were analysed.

    • In serum, the S/R ratios in the groups treated with 10, 20, or 100 mg kg−1 day−1 were 0.94, 0.83, and 0.34, respectively. The ratios were almost the same in the brain regions.

    • In the group treated with 100 mg kg−1 day−1, the serum and brain total CIT levels were found to be 20 times and 6 – 8 times higher than in the rats treated with 10 or 20 mg kg−1 day−1, respectively. In all groups, the CIT levels were higher in brain tissue as compared to serum.

    • In a spontaneous open-field behavioural test, a correlation between clinical and toxic drug concentrations was observed.

    • In conclusion, the R-enantiomer was present in an increased proportion compared with the S-enantiomer when higher steady-state CIT concentration was prevailing. This is of particular interest, since the S-enantiomer is responsible for the inhibition of serotonin reuptake in vitro. The present data may be of importance, as full understanding on where different racemic or enantiomeric drug effects of CIT and its main metabolites are unravelled.

  • 48.
    Kugelberg, Fredrik
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology.
    Apelqvist, Gustav
    Carlsson, Björn
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Pharmacology.
    Ahlner, Johan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology.
    Bengtsson, Finn
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Pharmacology.
    Sustained citalopram treatment in experimental hepatic encephalopathy: Effects on entrainment to the light-dark cycle and melatonin2006In: Basic & Clinical Pharmacology & Toxicology, ISSN 1742-7835, E-ISSN 1742-7843, Vol. 99, no 1, p. 80-88Article in journal (Refereed)
    Abstract [en]

    Patients with chronic hepatic encephalopathy often display altered diurnal rhythm as well as other affective disturbances which motivate treatment with antidepressants. We investigated the effects of sustained treatment with citalopram (10 mg/kg daily, 10 days) on 24-hr behavioural open-field activities in portacaval-shunted (PCS) rats and sham-operated control rats. In addition, the daytime and nighttime serum melatonin levels, as well as the serum concentrations of the enantiomers of citalopram and its metabolites, were analyzed. Untreated PCS rats showed reduced locomotor and rearing activities during nighttime. Citalopram treatment resulted in elevated behavioural activity in the PCS rats during night, indicative of an improved entrainment to the light-dark cycle, whereas no behavioural effect could be observed in sham rats. Higher melatonin levels in both PCS and sham rats were observed during nighttime compared with daytime, but the untreated PCS rats also showed higher daytime melatonin level than the corresponding sham group. Citalopram treatment seemed not to have any major effect on the melatonin levels. Higher serum levels of both citalopram and metabolites were observed in PCS rats as compared to sham rats. An altered ratio between the S- and R-enantiomers could also be observed in the PCS rats. In conclusion, the present data support the contention of a disturbed diurnal rhythm, and that the melatonin activity may be altered, in chronic hepatic encephalopathy. The citalopram treatment resulted in similar behavioural performances and daytime serum melatonin levels in PCS rats and controls, although pharmacokinetic differences were present between the groups. © Basic & Clinical Pharmacology & Toxicology 2006, All rights reserved.

  • 49.
    Kugelberg, Fredrik C.
    Linköping University, Department of Medicine and Care, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Chiral and toxicological aspects of citalopram: an experimental study in rats2003Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Citalopram (CIT) is a selective serotonin reuptake inhibitor (SSRI), which is used for the treatment of different psychiatric disorders. The indications for prescription of OT are linked to high risks for intentional intoxications. CIT is one of the most commonly found drugs in Swedish forensic autopsy cases. CIT is a chiral compound, which exists as a racemic mixture (50:50) of the S-(+)-enantiomer (S-CIT) and the R-(-)-enantiomer (R-CIT). The main metabolites, demethylcitalopram (DCIT) and didemethylcitalopram (DCIT), are also chiral compounds. The SSRI effect of CIT is mediated by S-CIT. The routine toxicological screening is an achiral analysis, in which the total amount of the two enantiomers of CIT and metabolites are measured. An extended analysis of the disposition of the Sand R-enantiomers may provide additional information in interpreting forensic toxicological results. Hence, the blood and brain dispositions of the enantiomers of CIT, DCIT and DDCIT in vivo as well as postmortem were studied in an animal model, which also included studies of the behavioural activity.

    Rats underwent systemic CIT exposure of clinically relevant and high/toxic doses, which were administered acute, chronic or acute-on-chronic. Samples from serum/blood and two brain regions (cortex and mesencephalon-pons) were collected for analysis of the concentrations of the enantiomers of CIT and metabolites using a chiral high performance liquid chromatography (HPLC) method. The open-field locomotor and rearing activities were examined after the chronic CIT exposure.

    Following chronic CIT administration, R-CIT was present in an increased proportion compared with S-CIT when higher CIT concentration prevailed. Higher drug levels were observed in brain than in serum, and the drug levels between the two compartments correlated well. The rats treated with the high/toxic dose displayed lower behavioural activity during the first test hour as compared to controls and rats given clinically relevant doses. No major effects of CIT on the behavioural rhythm were observed. Shortly after the acute CIT administration, the ratio between S- and R-CIT was close to unity, whereas R-OT was found in higher amount than S-CIT at the end of the study period. The heart blood levels of CIT and metabolites increased postmortem in comparison with the levels observed antemortem after acute, chronic and acute-on-chronic administration. Irrespective of administered dose, the ratios between the S- and R-enantiomers of CIT and DCIT, as well as the CIT/DCIT ratios, were similar antemortem and postmortem.

    Chiral analysis provided additional information regarding the different administration procedures as compared to achiral analysis. The stereoselective in vivo disposition of the enantiomers of CIT and metabolites was found similar in blood and brain. An equal degree of postmortem redistribution was also seen regarding the enantiomers of CIT and metabolites. These findings may facilitate and improve the interpretation of forensic toxicological results in humans.

    List of papers
    1. In vivo steady-state pharmacokinetic outcome following clinical and toxic doses of racemic citalopram to rats
    Open this publication in new window or tab >>In vivo steady-state pharmacokinetic outcome following clinical and toxic doses of racemic citalopram to rats
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    2001 (English)In: British Journal of Pharmacology, ISSN 0007-1188, E-ISSN 1476-5381, Vol. 132, no 8, p. 1683-1690Article in journal (Refereed) Published
    Abstract [en]
    • The thymoleptic drug citalopram (CIT) belongs to the selective serotonin reuptake inhibitors (SSRIs) and is today extensively used in psychiatry. Further clarification of the enantiomer-selective distribution of racemic CIT in both clinical and toxic doses is highly warranted.

    • By a steady-state in vivo paradigm, rats underwent chronic systemic exposure for 10 days by using osmotic pumps and the total as well as the individual distributions of the S- and R-enantiomers of CIT, and its metabolites in serum and two different brain regions, were analysed.

    • In serum, the S/R ratios in the groups treated with 10, 20, or 100 mg kg−1 day−1 were 0.94, 0.83, and 0.34, respectively. The ratios were almost the same in the brain regions.

    • In the group treated with 100 mg kg−1 day−1, the serum and brain total CIT levels were found to be 20 times and 6 – 8 times higher than in the rats treated with 10 or 20 mg kg−1 day−1, respectively. In all groups, the CIT levels were higher in brain tissue as compared to serum.

    • In a spontaneous open-field behavioural test, a correlation between clinical and toxic drug concentrations was observed.

    • In conclusion, the R-enantiomer was present in an increased proportion compared with the S-enantiomer when higher steady-state CIT concentration was prevailing. This is of particular interest, since the S-enantiomer is responsible for the inhibition of serotonin reuptake in vitro. The present data may be of importance, as full understanding on where different racemic or enantiomeric drug effects of CIT and its main metabolites are unravelled.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-26749 (URN)10.1038/sj.bjp.0704015 (DOI)11344 (Local ID)11344 (Archive number)11344 (OAI)
    Available from: 2009-10-08 Created: 2009-10-08 Last updated: 2017-12-13Bibliographically approved
    2. Effects of chronic citalopram treatment on central and peripheral spontaneous open-field behaviours in rats
    Open this publication in new window or tab >>Effects of chronic citalopram treatment on central and peripheral spontaneous open-field behaviours in rats
    2002 (English)In: Pharmacology and Toxicology, ISSN 0901-9928, E-ISSN 1600-0773, Vol. 90, no 6, p. 303-310Article in journal (Refereed) Published
    Abstract [en]

    The spontaneous open-field behavioural effects of 10 days of chronic treatment with two clinical doses (10 and 20 mg/kg daily) and one high/toxic dose (100 mg/kg daily) of the selective serotonin reuptake inhibitor citalopram (delivered subcutaneously by implanted osmotic pumps) were examined in rats. Central and peripheral arena locomotor and rearing activities were recorded simultaneously, and the data were assessed during the first hour as well as during the following 24 hr (the latter for effects on the diurnal rhythm). Rats treated with 100 mg/kg daily exhibited lower peripheral locomotor and rearing activities than the other groups during the first test hour. The ratio between central and peripheral activity increased in a dose-dependent non-proportional manner during the first test hour, indicating a general increase in the central arena activity exerted by the rats when treated with citalopram. No major differences were observed between any of the four groups in overall behavioural activities over the 24-hr period. This study indicated that the open-field locomotor and rearing behaviours in normal rats were affected by increasing doses of racemic citalopram, particularly during the first hour of adaptation.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-27659 (URN)10.1034/j.1600-0773.2002.900603.x (DOI)12397 (Local ID)12397 (Archive number)12397 (OAI)
    Available from: 2009-10-08 Created: 2009-10-08 Last updated: 2017-12-13Bibliographically approved
    3. Stereoselective single-dose kinetics of citalopram and its metabolites in rats
    Open this publication in new window or tab >>Stereoselective single-dose kinetics of citalopram and its metabolites in rats
    2003 (English)In: Chirality, ISSN 0899-0042, E-ISSN 1520-636X, Vol. 15, no 7, p. 622-629Article in journal (Refereed) Published
    Abstract [en]

    The single-dose kinetics of the enantiomers of citalopram (CIT) and its metabolites, demethylcitalopram (DCIT) and didemethylcitalopram (DDCIT), were investigated after administration of 10, 20, or 100 mg/kg (s.c.) rac-CIT to rats. Samples from serum and two brain regions were collected 1, 3, 10, or 20 h postdose for HPLC analysis. In the 100 mg/kg rats, the enantiomeric (S/R) serum concentration ratios of CIT decreased during the study period (0.93 at 1 h vs. 0.59 at 20 h; P < 0.001). In the 10 and 20 mg/kg rats, the decrease in serum S/R CIT ratios was not so evident as in the 100 mg/kg rats. In all three groups the S/R CIT ratio was almost the same in the brain as in serum, although both CIT enantiomer levels in the brain were found to be 5–10 times higher than the levels in serum. The serum and brain metabolite levels were low in the 10 and 20 mg/kg rats, whereas the levels increased during the study period in the 100 mg/kg rats. In conclusion, the CIT enantiomers were shown for the first time to be stereoselectively metabolized after single-dose administration to rats, as previously shown in steady-state dosing studies in humans and rats. Chirality 15:622–629, 2003. © 2003 Wiley-Liss, Inc.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-26746 (URN)10.1002/chir.10266 (DOI)11341 (Local ID)11341 (Archive number)11341 (OAI)
    Available from: 2009-10-08 Created: 2009-10-08 Last updated: 2017-12-13Bibliographically approved
    4. Postmortem redistribution of the enantiomers of citalopram and its metabolites: an experimental study in rats
    Open this publication in new window or tab >>Postmortem redistribution of the enantiomers of citalopram and its metabolites: an experimental study in rats
    Show others...
    2004 (English)In: Journal of Analytical Toxicology, ISSN 0146-4760, E-ISSN 1945-2403, Vol. 28, no 8, p. 631-637Article in journal (Refereed) Published
    Abstract [en]

    A rat model was used to study if postmortem redistribution of the S- and R-enantiomers of citalopram (CIT) and its metabolites demethylcitalopram (DCIT) and didemethylcitalopram (DDCIT) occurs after three different subcutaneous dosing procedures with racemic CIT. Two groups underwent chronic administration (20 mg/kg daily) using osmotic pumps. After 10 days, 1 of these groups received an acute-on-chronic drug challenge with a single injection of 100 mg/kg. The third group received the single 100 mg/kg dose only. Heart blood and brain samples were collected antemortem and 1, 3, or 24 h postmortem for enantioselective HPLC analysis. Increased postmortem blood drug and metabolite concentrations compared with corresponding antemortem concentrations were observed in all groups (p < 0.05 to p < 0.001). At 24 h after death, the ratios between postmortem and antemortem blood concentrations were around 3–4 for CIT as well as for the metabolites. In the brain, no major differences between antemortem and postmortem drug and metabolite concentrations were observed. The enantiomeric (S/R) concentrations ratios of CIT and metabolites in blood and brain were of similar magnitude before and after death. No differences between antemortem and postmortem parent drug-to-metabolite (P/M) ratios for CIT/DCIT in blood were observed. Finally, this animal model demonstrates that the S- and R-enantiomers of CIT and its metabolites were redistributed to the same extent postmortem.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-24023 (URN)10.1093/jat/28.8.631 (DOI)3578 (Local ID)3578 (Archive number)3578 (OAI)
    Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2017-12-13Bibliographically approved
  • 50.
    Kugelberg, Fredrik C.
    et al.
    Linköping University, Department of Medicine and Care, Clinical Pharmacology. Linköping University, Department of Neuroscience and Locomotion, Psychiatry. Linköping University, Faculty of Health Sciences.
    Apelqvist, Gustav
    Department of Clinical Pharmacology, Institute of Laboratory Medicine,Lund University, Lund, Sweden.
    Bengtsson, Finn
    Linköping University, Department of Medicine and Care, Clinical Pharmacology. Linköping University, Department of Neuroscience and Locomotion, Psychiatry. Linköping University, Faculty of Health Sciences.
    Effects of chronic citalopram treatment on central and peripheral spontaneous open-field behaviours in rats2002In: Pharmacology and Toxicology, ISSN 0901-9928, E-ISSN 1600-0773, Vol. 90, no 6, p. 303-310Article in journal (Refereed)
    Abstract [en]

    The spontaneous open-field behavioural effects of 10 days of chronic treatment with two clinical doses (10 and 20 mg/kg daily) and one high/toxic dose (100 mg/kg daily) of the selective serotonin reuptake inhibitor citalopram (delivered subcutaneously by implanted osmotic pumps) were examined in rats. Central and peripheral arena locomotor and rearing activities were recorded simultaneously, and the data were assessed during the first hour as well as during the following 24 hr (the latter for effects on the diurnal rhythm). Rats treated with 100 mg/kg daily exhibited lower peripheral locomotor and rearing activities than the other groups during the first test hour. The ratio between central and peripheral activity increased in a dose-dependent non-proportional manner during the first test hour, indicating a general increase in the central arena activity exerted by the rats when treated with citalopram. No major differences were observed between any of the four groups in overall behavioural activities over the 24-hr period. This study indicated that the open-field locomotor and rearing behaviours in normal rats were affected by increasing doses of racemic citalopram, particularly during the first hour of adaptation.

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