1
|
Manchester KR, Waters L, Haider S, Maskell PD. The blood-to-plasma ratio and predicted GABA A-binding affinity of designer benzodiazepines. Forensic Toxicol 2022; 40:349-356. [PMID: 36454409 PMCID: PMC9715504 DOI: 10.1007/s11419-022-00616-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 02/16/2022] [Indexed: 01/26/2023]
Abstract
PURPOSE The number of benzodiazepines appearing as new psychoactive substances (NPS) is continually increasing. Information about the pharmacological parameters of these compounds is required to fully understand their potential effects and harms. One parameter that has yet to be described is the blood-to-plasma ratio. Knowledge of the pharmacodynamics of designer benzodiazepines is also important, and the use of quantitative structure-activity relationship (QSAR) modelling provides a fast and inexpensive method of predicting binding affinity to the GABAA receptor. METHODS In this work, the blood-to-plasma ratios for six designer benzodiazepines (deschloroetizolam, diclazepam, etizolam, meclonazepam, phenazepam, and pyrazolam) were determined. A previously developed QSAR model was used to predict the binding affinity of nine designer benzodiazepines that have recently appeared. RESULTS Blood-to-plasma values ranged from 0.57 for phenazepam to 1.18 to pyrazolam. Four designer benzodiazepines appearing since 2017 (fluclotizolam, difludiazepam, flualprazolam, and clobromazolam) had predicted binding affinities to the GABAA receptor that were greater than previously predicted binding affinities for other designer benzodiazepines. CONCLUSIONS This work highlights the diverse nature of the designer benzodiazepines and adds to our understanding of their pharmacology. The greater predicted binding affinities are a potential indication of the increasing potency of designer benzodiazepines appearing on the illicit drugs market.
Collapse
Affiliation(s)
- Kieran R. Manchester
- grid.6268.a0000 0004 0379 5283School of Nursing and Healthcare Leadership, University of Bradford, Bradford, UK
| | - Laura Waters
- grid.15751.370000 0001 0719 6059School of Applied Sciences, University of Huddersfield, Huddersfield, UK
| | - Shozeb Haider
- grid.83440.3b0000000121901201School of Pharmacy, University College London, London, UK
| | - Peter D. Maskell
- grid.8756.c0000 0001 2193 314XForensic Medicine and Science, University of Glasgow, Glasgow, UK
| |
Collapse
|
2
|
Favretto D, Visentin S, Jones AW. Prevalence and concentrations of sedative-hypnotic drugs in blood of drivers involved in road traffic crashes in the Padova region of Italy - not so easy to interpret. Forensic Sci Int 2021; 330:111097. [PMID: 34814082 DOI: 10.1016/j.forsciint.2021.111097] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 10/31/2021] [Accepted: 11/02/2021] [Indexed: 11/28/2022]
Abstract
BACKGROUND & OBJECTIVES This study reports the prevalence and concentrations of sedative-hypnotic drugs as exemplified by benzodiazepines (BZD) and zolpidem (Z-hypnotic) in blood samples from drivers involved in road traffic accidents (RTA) in the Padova region of Italy. Another aim of the study was to estimate the prevalence of these drugs with concentrations in blood above the therapeutic intervals and above specific per se limits. METHODS A total of 4066 blood samples collected from drivers involved in RTA were analysed for the presence of alcohol, drugs of abuse and medicinal drugs with sedative-hypnotic properties. Prevalence of drivers positive for BZDs and zolpidem were reported according to the reporting limit of our laboratory (1 ng/mL) in a sort of zero tolerance approach and compared with the prevalence according to analytical cut-offs used in the "European Union's research project on Driving Under the Influence of Drugs, Alcohol and Medicines" (DRUID). The impairment-based, per se limits adopted in Norway and in England and Wales and the values used to define "therapeutic ranges" in blood and in plasma/serum were also applied to the case study. RESULTS 175 blood samples were positive for sedative-hypnotics above 1 ng/mL, with the following prevalence: diazepam 44%, nordazepam 41.8%, lorazepam 32.6%, zolpidem 28%, oxazepam 25.6%, alprazolam 16%, delorazepam 11,6%, lormetazepam 11,6%, temazepam 11.6%, clonazepam 11.6%, triazolam 6.9%, N-desalkylflurazepam 4.6%, bromazepam 2.3%. When applying DRUID analytical cut-offs, the prevalence of BZDs and zolpidem sharply decreases. Applying the impairing cut-offs used in Norway, 56% of positive samples were above the limits equivalent to a BAC of 0.2 g/L, 39% above the limits corresponding to 0.5 g/L, and 23% above the cut-off corresponding to 1.2 g/L. Only 1% of the drivers had drug concentrations above the per se concentration limits adopted in England and Wales [26]. When comparing blood levels with therapeutic ranges in plasma, bromazepam, lormetazepam and delorazepam were often found above the highest limits. The adjustment of the concentrations with the plasma-to-blood ratios causes a significant increase of cases above the therapeutic ranges in plasma. CONCLUSIONS Sedative-hypnotic drugs are medicinal substances frequently identified in drivers involved in RTA, commonly in concentrations associated with driving impairment. Besides the concentrations of drugs in blood, several factors have to be considered to conclude that a driver was impaired. The frequent association with alcohol, cocaine and other BZDs, confirms the abuse potential of these medications.
Collapse
Affiliation(s)
- Donata Favretto
- University Hospital of Padova, Legal Medicine and Toxicology, Via Falloppio 50, Padova, Italy.
| | | | - Alan W Jones
- Division of Drug Research, Department of Biomedical and Clinical Sciences, Linköping University, SE-581 85 Linköping, Sweden.
| |
Collapse
|
3
|
Czerwinska J, Parkin MC, George C, Kicman AT, Dargan PI, Abbate V. Pharmacokinetics of Mephedrone and Its Metabolites in Whole Blood and Plasma after Controlled Intranasal Administration to Healthy Human Volunteers. J Anal Toxicol 2021; 45:730-738. [PMID: 32986113 DOI: 10.1093/jat/bkaa134] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 08/21/2020] [Accepted: 09/23/2020] [Indexed: 12/14/2022] Open
Abstract
Mephedrone is a popular synthetic cathinone, known for its psychostimulant effects. At present, there is no data available on the pharmacokinetics of mephedrone and its metabolites in concurrently collected whole blood and plasma samples after a controlled intranasal administration to healthy volunteers. In this study, six healthy male volunteers nasally insufflated 100 mg of pure mephedrone hydrochloride (Day 1). Whole blood and plasma samples were collected at different time points after the administration and were analyzed for the presence of mephedrone and its metabolites, dihydro-mephedrone (DHM), nor-mephedrone (NOR), hydroxytolyl-mephedrone (HYDROXY), 4-carboxy-mephedrone (4-CARBOXY) and dihydro-nor-mephedrone (DHNM), by validated liquid chromatography-tandem mass spectrometry methods. All analytes were detected in whole blood and plasma for 6 h post administration, with mephedrone and NOR also being detectable on Day 2 in some participants. 4-CARBOXY, followed by NOR, was the most abundant metabolite in both matrices. Compared to other psychostimulants, mephedrone showed rapid absorption (mean Tmax of 52.5 ± 20.7 min in plasma and 55.0 ± 18.2 min in whole blood) and elimination (mean t1/2 of 1.98 ± 0.30 h in plasma and 2.12 ± 0.33 h in whole blood). In addition, statistical analysis showed that median whole blood to plasma distribution ratios, reported here for the first time, were statistically different from 1 (unity) for mephedrone (median: 1.11), DHM (median: 1.30) and NOR (median: 0.765). It is hoped that the study will aid forensic and clinical toxicologists in detection, identification and interpretation of cases associated with mephedrone use.
Collapse
Affiliation(s)
- Joanna Czerwinska
- King's Forensics, Department of Analytical, Environmental and Forensic Sciences, King's College London, London, UK
| | - Mark C Parkin
- King's Forensics, Department of Analytical, Environmental and Forensic Sciences, King's College London, London, UK.,Eurofins Forensic Services, Toxicology Department, Teddington, UK
| | | | - Andrew T Kicman
- King's Forensics, Department of Analytical, Environmental and Forensic Sciences, King's College London, London, UK
| | - Paul I Dargan
- Clinical Toxicology, Guy's and St Thomas' NHS Foundation Trust and King's Health Partners, London, UK.,Clinical Toxicology, Faculty of Life Sciences and Medicine, King's College London, London, UK
| | - Vincenzo Abbate
- King's Forensics, Department of Analytical, Environmental and Forensic Sciences, King's College London, London, UK
| |
Collapse
|
4
|
Ji B, Xue Y, Xu Y, Liu S, Gough AH, Xie XQ, Wang J. Drug-Drug Interaction Between Oxycodone and Diazepam by a Combined in Silico Pharmacokinetic and Pharmacodynamic Modeling Approach. ACS Chem Neurosci 2021; 12:1777-1790. [PMID: 33950681 PMCID: PMC8374491 DOI: 10.1021/acschemneuro.0c00810] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Opioids and benzodiazepines have complex drug-drug interactions (DDIs), which serve as an important source of adverse drug effects. In this work, we predicted the DDI between oxycodone (OXY) and diazepam (DZP) in the human body by applying in silico pharmacokinetic (PK) and pharmacodynamic (PD) modeling and simulation. First, we studied the PK interaction between OXY and DZP with a physiologically based pharmacokinetic (PBPK) model. Second, we applied molecular modeling techniques including molecular docking, molecular dynamics (MD) simulation, and the molecular mechanics/Poisson-Boltzmann surface area (MM-PBSA) free energy method to predict the PD-DDI between these two drugs. The PK interaction between OXY and DZP predicted by the PBPK model was not obvious. No significant interaction was observed between the two drugs at normal doses, though very high doses of DZP demonstrated a non-negligible inhibitory effect on OXY metabolism. On the contrary, the molecular modeling study shows that DZP has potential to compete with OXY at the same binding pocket of the active μ-opioid receptor (MOR) and κ-opioid receptor (KOR). MD simulation and MM-PBSA calculation results demonstrated that there is likely a synergetic effect between OXY and DZP binding to opioid receptors, as OXY is likely to target the active MOR while DZP selectively binds to the active KOR. Thus, pharmacokinetics contributes slightly to the DDI between OXY and DZP although an overdose of DZP has been brought to attention. Pharmacodynamics is likely to play a more important role than pharmacokinetics in revealing the mechanism of DDI between OXY and DZP.
Collapse
Affiliation(s)
- Beihong Ji
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, The University of Pittsburgh, 3501 Terrace St, Pittsburgh, PA 15261,NIH National Center of Excellence for Computational Drug Abuse Research, The University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, USA
| | - Ying Xue
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, The University of Pittsburgh, 3501 Terrace St, Pittsburgh, PA 15261,NIH National Center of Excellence for Computational Drug Abuse Research, The University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, USA.,Department of Pharmacy and Therapeutics, School of Pharmacy, The University of Pittsburgh, 3501 Terrace St, Pittsburgh, PA 15261
| | - Yuanyuan Xu
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, The University of Pittsburgh, 3501 Terrace St, Pittsburgh, PA 15261,NIH National Center of Excellence for Computational Drug Abuse Research, The University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, USA
| | - Shuhan Liu
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, The University of Pittsburgh, 3501 Terrace St, Pittsburgh, PA 15261,NIH National Center of Excellence for Computational Drug Abuse Research, The University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, USA
| | - Albert H Gough
- Computational and Systems Biology, The University of Pittsburgh, Drug Discovery Institute, 800 Murdoch Building, 3420 Forbes Avenue, Pittsburgh, Pennsylvania, 15260, USA
| | - Xiang Qun Xie
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, The University of Pittsburgh, 3501 Terrace St, Pittsburgh, PA 15261,NIH National Center of Excellence for Computational Drug Abuse Research, The University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, USA.,To whom correspondence should be addressed: Xiang-Qun Xie: Corresponding author, , School of Pharmacy, University of Pittsburgh; Junmei Wang: Corresponding author, , School of Pharmacy, University of Pittsburgh
| | - Junmei Wang
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, The University of Pittsburgh, 3501 Terrace St, Pittsburgh, PA 15261,NIH National Center of Excellence for Computational Drug Abuse Research, The University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, USA.,To whom correspondence should be addressed: Xiang-Qun Xie: Corresponding author, , School of Pharmacy, University of Pittsburgh; Junmei Wang: Corresponding author, , School of Pharmacy, University of Pittsburgh
| |
Collapse
|
5
|
Study on the Pharmacokinetics of Diazepam and Its Metabolites in Blood of Chinese People. Eur J Drug Metab Pharmacokinet 2020; 45:477-485. [DOI: 10.1007/s13318-020-00614-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
6
|
Menzies EL, Archer JR, Dargan PI, Parkin MC, Yamamoto T, Wood DM, Braithwaite RA, Elliott SP, Kicman AT. Detection of cocaine and its metabolites in whole blood and plasma following a single dose, controlled administration of intranasal cocaine. Drug Test Anal 2019; 11:1419-1430. [DOI: 10.1002/dta.2657] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 05/23/2019] [Accepted: 05/27/2019] [Indexed: 01/04/2023]
Affiliation(s)
- Eleanor L. Menzies
- Analytical and Environmental Sciences Research Division, Faculty of Life Sciences and MedicineKing's College London UK
| | - John R.H. Archer
- Clinical ToxicologyGuy's and St Thomas' NHS Foundation Trust London UK
- Clinical Toxicology, Faculty of Life Sciences and Medicine, King's College LondonSt Thomas' Hospital London UK
| | - Paul I. Dargan
- Clinical ToxicologyGuy's and St Thomas' NHS Foundation Trust London UK
- Clinical Toxicology, Faculty of Life Sciences and Medicine, King's College LondonSt Thomas' Hospital London UK
| | - Mark C. Parkin
- Analytical and Environmental Sciences Research Division, Faculty of Life Sciences and MedicineKing's College London UK
| | - Takahiro Yamamoto
- Clinical ToxicologyGuy's and St Thomas' NHS Foundation Trust London UK
| | - David M. Wood
- Clinical ToxicologyGuy's and St Thomas' NHS Foundation Trust London UK
- Clinical Toxicology, Faculty of Life Sciences and Medicine, King's College LondonSt Thomas' Hospital London UK
| | - Robin A. Braithwaite
- Analytical and Environmental Sciences Research Division, Faculty of Life Sciences and MedicineKing's College London UK
| | - Simon P. Elliott
- Alere ForensicsMalvern Hills Science Park Malvern Worcestershire UK
| | - Andrew T. Kicman
- Analytical and Environmental Sciences Research Division, Faculty of Life Sciences and MedicineKing's College London UK
| |
Collapse
|
7
|
Liao HW, Lin SW, Lin YT, Lee CH, Kuo CH. Identification of potential sphingomyelin markers for the estimation of hematocrit in dried blood spots via a lipidomic strategy. Anal Chim Acta 2018; 1003:34-41. [DOI: 10.1016/j.aca.2017.11.041] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 11/16/2017] [Accepted: 11/17/2017] [Indexed: 11/28/2022]
|
8
|
|
9
|
Post-mortem concentrations of drugs determined in femoral blood in single-drug fatalities compared with multi-drug poisoning deaths. Forensic Sci Int 2016; 267:96-103. [DOI: 10.1016/j.forsciint.2016.08.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 07/26/2016] [Accepted: 08/05/2016] [Indexed: 11/17/2022]
|
10
|
Ralvenius WT, Acuña MA, Benke D, Matthey A, Daali Y, Rudolph U, Desmeules J, Zeilhofer HU, Besson M. The clobazam metabolite N-desmethyl clobazam is an α2 preferring benzodiazepine with an improved therapeutic window for antihyperalgesia. Neuropharmacology 2016; 109:366-375. [PMID: 27392635 PMCID: PMC4981430 DOI: 10.1016/j.neuropharm.2016.07.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 05/27/2016] [Accepted: 07/04/2016] [Indexed: 12/14/2022]
Abstract
Data from genetically modified mice suggest that benzodiazepine (BDZ)-site agonists with improved selectivity for α2-subtype GABAA receptors (α2GABAAR) are potentially useful for the treatment of neuropathic pain. Subtype-selective compounds available for preclinical tests in rodents support this concept but have not been approved for human use, hindering proof-of-concept studies in patients. We recently proposed that N-desmethyl clobazam (NDMC), the main metabolite of the licensed BDZ clobazam (CBZ), is responsible for most of the antihyperalgesia observed in mice after CBZ administration. In order to assess a potentially favorable pharmacological profile of NDMC, we analyzed differences in the GABAAR subtype specificity of CBZ, NDMC and diazepam (DZP) in recombinant receptors. DZP and CBZ potentiated sedating α1GABAARs and antihyperalgesic α2GABAARs with similar efficacies, whereas NDMC preferred α2GABAARs over α1GABAARs across a wide concentration range. In vivo, DZP and NDMC reduced neuropathic pain at doses between 3 and 30 mg/kg. At these doses, DZP had strong locomotor sedating effects while NDMC caused no or only weak sedation. Sedative effects of NDMC became apparent when the action of NDMC was restricted to α1GABAARs. However, when GABAAR point-mutated mice were studied that allow the analysis of antihyperalgesia and sedation in isolation, we found that, compared to DZP, NDMC had a significantly improved therapeutic window, consistent with its more favorable α2/α1 in vitro activity ratio. Given that NDMC should share the safety profile of its parent compound CBZ, it should be well-suited for proof-of-concept studies in human volunteers or patients.
Collapse
Affiliation(s)
- William T Ralvenius
- Institute of Pharmacology and Toxicology, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Mario A Acuña
- Institute of Pharmacology and Toxicology, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Dietmar Benke
- Institute of Pharmacology and Toxicology, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Alain Matthey
- Division of Clinical Pharmacology and Toxicology, Multidisciplinary Pain Center, Department of Anesthesiology, Pharmacology and Intensive Care, Geneva University Hospitals, University of Geneva, 4 rue Gabrielle-Perret-Gentil, CH-1211 Geneva, Switzerland
| | - Youssef Daali
- Division of Clinical Pharmacology and Toxicology, Multidisciplinary Pain Center, Department of Anesthesiology, Pharmacology and Intensive Care, Geneva University Hospitals, University of Geneva, 4 rue Gabrielle-Perret-Gentil, CH-1211 Geneva, Switzerland
| | - Uwe Rudolph
- Laboratory of Genetic Neuropharmacology, McLean Hospital, 115 Mill Street, Belmont, MA 02478, USA; Department of Psychiatry, Harvard Medical School, 401 Park Drive, Boston, MA 02215, USA
| | - Jules Desmeules
- Division of Clinical Pharmacology and Toxicology, Multidisciplinary Pain Center, Department of Anesthesiology, Pharmacology and Intensive Care, Geneva University Hospitals, University of Geneva, 4 rue Gabrielle-Perret-Gentil, CH-1211 Geneva, Switzerland
| | - Hanns Ulrich Zeilhofer
- Institute of Pharmacology and Toxicology, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland; Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology (ETH) Zurich, Vladimir-Prelog-Weg 10, CH-8093 Zürich, Switzerland; Drug Discovery Network Zurich (DDNZ), CH-8057 Zurich, Switzerland.
| | - Marie Besson
- Division of Clinical Pharmacology and Toxicology, Multidisciplinary Pain Center, Department of Anesthesiology, Pharmacology and Intensive Care, Geneva University Hospitals, University of Geneva, 4 rue Gabrielle-Perret-Gentil, CH-1211 Geneva, Switzerland
| |
Collapse
|
11
|
Kanegawa N, Collste K, Forsberg A, Schain M, Arakawa R, Jucaite A, Lekander M, Olgart Höglund C, Kosek E, Lampa J, Halldin C, Farde L, Varrone A, Cervenka S. In vivo evidence of a functional association between immune cells in blood and brain in healthy human subjects. Brain Behav Immun 2016; 54:149-157. [PMID: 26820224 DOI: 10.1016/j.bbi.2016.01.019] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 12/27/2015] [Accepted: 01/23/2016] [Indexed: 11/24/2022] Open
Abstract
Microglia, the resident macrophages in the central nervous system, are thought to be maintained by a local self-renewal mechanism. Although preclinical and in vitro studies have suggested that the brain may contain immune cells also from peripheral origin, the functional association between immune cells in the periphery and brain at physiological conditions is poorly understood. We examined 32 healthy individuals using positron emission tomography (PET) and [(11)C]PBR28, a radioligand for the 18-kDa translocator protein (TSPO) which is expressed both in brain microglia and blood immune cells. In 26 individuals, two measurements were performed with varying time intervals. In a subgroup of 19 individuals, of which 12 had repeat examinations, leukocyte numbers in blood was measured on each day of PET measurements. All individuals were genotyped for TSPO polymorphism and categorized as high, mixed, and low affinity binders. We assessed TSPO binding expressed as total distribution volume of [(11)C]PBR28 in brain and in blood cells. TSPO binding in brain was strongly and positively correlated to binding in blood cells both at baseline and when analyzing change between two PET examinations. Furthermore, there was a significant correlation between change of leukocyte numbers and change in TSPO binding in brain, and a trend-level correlation to change in TSPO binding in blood cells. These in vivo findings indicate an association between immunological cells in blood and brain via intact BBB, suggesting a functional interaction between these two compartments, such as interchange of peripherally derived cells or a common regulatory mechanism. Measurement of radioligand binding in blood cells may be a way to control for peripheral immune function in PET studies using TSPO as a marker of brain immune activation.
Collapse
Affiliation(s)
- Naoki Kanegawa
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, Stockholm, Sweden
| | - Karin Collste
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, Stockholm, Sweden
| | - Anton Forsberg
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, Stockholm, Sweden
| | - Martin Schain
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, Stockholm, Sweden
| | - Ryosuke Arakawa
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, Stockholm, Sweden
| | - Aurelija Jucaite
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, Stockholm, Sweden
| | - Mats Lekander
- Department of Clinical Neuroscience, Osher Center for Integrative Medicine, Karolinska Institutet, Stockholm, Sweden; Stress Research Institute, Stockholm University, Stockholm, Sweden
| | - Caroline Olgart Höglund
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; Department of Medicine Solna and CMM, Karolinska Institutet and Karolinska University Hospital Solna, Stockholm, Sweden
| | - Eva Kosek
- Department of Clinical Neuroscience, Osher Center for Integrative Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Jon Lampa
- Department of Medicine, Rheumatology Unit, Center of Molecular Medicine (CMM), Karolinska Institutet, Stockholm, Sweden
| | - Christer Halldin
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, Stockholm, Sweden
| | - Lars Farde
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, Stockholm, Sweden
| | - Andrea Varrone
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, Stockholm, Sweden
| | - Simon Cervenka
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, Stockholm, Sweden.
| |
Collapse
|
12
|
Jones AW, Gladh SA, Windberg CN, Johansen SS. Stability of -Hydroxybutyrate in Blood Samples from Impaired Drivers after Storage at 4 C and Comparison of GC-FID-GBL and LC-MS-MS Methods of Analysis. J Anal Toxicol 2015; 39:294-9. [DOI: 10.1093/jat/bkv007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
13
|
Sedative and hypnotic drugs—Fatal and non-fatal reference blood concentrations. Forensic Sci Int 2014; 236:138-45. [DOI: 10.1016/j.forsciint.2014.01.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Revised: 12/30/2013] [Accepted: 01/05/2014] [Indexed: 11/20/2022]
|
14
|
Langel K, Gjerde H, Favretto D, Lillsunde P, Øiestad EL, Ferrara SD, Verstraete AG. Comparison of drug concentrations between whole blood and oral fluid. Drug Test Anal 2013; 6:461-71. [PMID: 24039237 DOI: 10.1002/dta.1532] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 08/08/2013] [Accepted: 08/08/2013] [Indexed: 11/10/2022]
Abstract
The relationship of drug concentrations between oral fluid and whole blood was evaluated by studying the linear correlation of concentrations and calculating the oral fluid to blood concentration ratios (OF/B) for different substances. Paired oral fluid and whole blood samples were collected from volunteers and persons suspected of drug use in four European countries. Oral fluid samples were collected with the Saliva∙Sampler™ device. All samples were analyzed for drugs of abuse and psychoactive medicines with validated gas and liquid chromatography-mass spectrometric methods. The median OF/B ratios were, for amphetamines 19-22, for opioids 1.8-11, for cocaine and metabolites 1.7-17, for tetrahydrocannabinol (THC) 14, for benzodiazepines 0.035-0.33, and for other psychoactive medicines 0.24-3.7. Most of the these results were close to theoretical values based on the physicochemical properties of the drugs and to values presented earlier, but there was a lot of inter-individual variation in the OF/B ratios. For all substances, except for lorazepam (R(2) = 0.031) and THC (R(2) = 0.030), a correlation between the oral fluid and whole blood concentrations was observed. Due to large variation seen here, drug findings in oral fluid should not be used to estimate the corresponding concentrations in whole blood (or vice versa). However, detection of drugs in oral fluid is a sign of recent drug use and oral fluid can be used for qualitative detection of several drugs, e.g. in epidemiological prevalence studies. By optimizing the sampling and the analytical cut-offs, the potential of oral fluid as a confirmation matrix could be enhanced.
Collapse
Affiliation(s)
- Kaarina Langel
- Department of Alcohol, Drugs, and Addiction, National Institute for Health and Welfare, Helsinki, Finland
| | | | | | | | | | | | | |
Collapse
|
15
|
Launiainen T, Ojanperä I. Drug concentrations in post-mortem femoral blood compared with therapeutic concentrations in plasma. Drug Test Anal 2013; 6:308-16. [PMID: 23881890 PMCID: PMC4237191 DOI: 10.1002/dta.1507] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Revised: 06/06/2013] [Accepted: 06/06/2013] [Indexed: 12/04/2022]
Abstract
Therapeutic drug concentrations measured in plasma are of limited value as reference intervals for interpretation in post-mortem (PM) toxicology. In this study, drug concentration distributions were studied in PM femoral venous blood from 57 903 Finnish autopsy cases representing all causes of death during an 11-year period. Cause-of-death information was obtained from death certificates issued by forensic pathologists. Median, mean, and upper percentile (90th, 95th, 97.5th) concentrations were calculated for 129 drugs. To illustrate how PM median concentrations relate to established therapeutic ranges in plasma, a PM blood/plasma relationship was calculated for each drug. Males represented 75% of the subjects and showed a lower median age (55 yrs) than females (59 yrs). In 43% of these cases, blood alcohol concentration was higher than 0.2‰, and the median was 1.8‰. Sixty-one (47%) of the 129 drugs showed a PM blood/plasma relationship of 1. For 22 drugs (17%), the relationship was <1, and for 46 drugs (35%), the relationship was >1. No marked correlation was found between the PM blood/plasma relationship and the volume of distribution (Vd). For 36 drugs, more than 10% of cases were fatal poisonings attributed to this drug as the main finding. These drug concentration distributions based on a large database provide a helpful reference not only to forensic toxicologists and pathologists but also to clinical pharmacologists in charge of interpreting drug concentrations in PM cases. © 2013 The Authors. Drug Testing and Analysis published by John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
- Terhi Launiainen
- University of Helsinki, Hjelt Institute, Department of Forensic Medicine, PO Box 40 (Kytösuontie 11), FI-00014, Helsinki, Finland
| | | |
Collapse
|
16
|
Hsu YC, Chen BG, Yang SC, Wang YS, Huang SP, Huang MH, Chen TJ, Liu HC, Lin DL, Liu RH, Jones AW. Methadone concentrations in blood, plasma, and oral fluid determined by isotope-dilution gas chromatography–mass spectrometry. Anal Bioanal Chem 2012; 405:3921-8. [DOI: 10.1007/s00216-012-6460-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2012] [Revised: 08/29/2012] [Accepted: 09/26/2012] [Indexed: 11/24/2022]
|
17
|
Jones AW, Holmgren A. Concentrations of zolpidem and zopiclone in venous blood samples from impaired drivers compared with femoral blood from forensic autopsies. Forensic Sci Int 2012; 222:118-23. [DOI: 10.1016/j.forsciint.2012.05.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Revised: 05/03/2012] [Accepted: 05/06/2012] [Indexed: 11/28/2022]
|
18
|
Jones AW, Holmgren A. Concentrations of diazepam and nordiazepam in 1,000 blood samples from apprehended drivers--therapeutic use or abuse of anxiolytics? J Pharm Pract 2012; 26:198-203. [PMID: 22797834 DOI: 10.1177/0897190012451910] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Using an in-house forensic toxicology database, we selected 1000 cases of driving under the influence of drugs (DUIDs) over a 12-month period if diazepam (D) and nordiazepam (ND) were both present in the blood samples. Quantitative analysis of D and ND in blood was done by solvent extraction (butyl acetate) and capillary column gas chromatography (GC) with a nitrogen-phosphorous (N-P) detector. The limits of quantitation of this analytical method for D and ND in blood were 0.05 mg/L. The correlation between D and ND concentrations in blood was statistically significant (r = .58, P < .001), as expected for a parent drug and its primary metabolite. However, the frequency distributions were markedly skewed to the right with mean (median) and highest concentrations of 0.37 (0.20) and 6.1 mg/L for D and 0.39 (0.20) and 5.6 mg/L for ND. The mean (median) total concentration (D + ND) was 0.76 mg/L (0.50 mg/L), and the concentration ratios D/ND and ND/D were 1.29 (median 0.95) and 1.41 (median 1.06), respectively. In 90 cases (9%), the concentration of D in blood exceeded 0.83 mg/L, which corresponds to an upper therapeutic limit in plasma (∼1.5 mg/L), assuming a plasma/blood distribution ratio of 1.8:1.
Collapse
Affiliation(s)
- Alan W Jones
- Department of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Linköping, Sweden.
| | | |
Collapse
|
19
|
Tan A, Gagné S, Lévesque IA, Lachance S, Boudreau N, Lévesque A. Impact of hemolysis during sample collection: How different is drug concentration in hemolyzed plasma from that of normal plasma? J Chromatogr B Analyt Technol Biomed Life Sci 2012; 901:79-84. [DOI: 10.1016/j.jchromb.2012.06.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2012] [Revised: 05/26/2012] [Accepted: 06/01/2012] [Indexed: 10/28/2022]
|
20
|
Discovery pharmacokinetic studies in mice using serial microsampling, dried blood spots and microbore LC–MS/MS. Bioanalysis 2012; 4:1077-95. [DOI: 10.4155/bio.12.85] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Background: Initial pharmacokinetic (PK) studies of discovery compounds are conducted in mice to demonstrate exposure prior to conducting efficacy studies. PK information obtained from a single mouse by serial blood microsampling, dried blood spot collection and analyses using microbore (1 mm internal diameter column) LC–MS/MS is presented. Ex vivo blood to plasma concentration ratios (BPRs) from mouse PK studies were compared with in vitro BPRs for 15 compounds. Results: Two compounds were orally dosed and blood was collected at time points via serial blood sampling. The calculated PK parameters (AUC, Tmax and Cmax) were comparable across liquid blood, dried blood spot and plasma matrices. The BPR results from both methods were comparable. Conclusion: Serial blood microsampling has led to reduced animal and compound usage with improved PK data. Ex vivo BPR is suitable in a discovery setting. Microbore LC–MS/MS is well suited in instances where sample volume is limited, and enables faster analyses, reduced solvent use, and less frequent MS source cleaning.
Collapse
|
21
|
Sjögren E, Bredberg U, Lennernäs H. The Pharmacokinetics and Hepatic Disposition of Repaglinide in Pigs: Mechanistic Modeling of Metabolism and Transport. Mol Pharm 2012; 9:823-41. [DOI: 10.1021/mp200218p] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Erik Sjögren
- Department of Pharmacy, Uppsala University, Box 580, S-751 23 Uppsala, Sweden
| | | | - Hans Lennernäs
- Department of Pharmacy, Uppsala University, Box 580, S-751 23 Uppsala, Sweden
| |
Collapse
|
22
|
Vuckovic D, de Lannoy I, Gien B, Yang Y, Musteata FM, Shirey R, Sidisky L, Pawliszyn J. In vivo solid-phase microextraction for single rodent pharmacokinetics studies of carbamazepine and carbamazepine-10,11-epoxide in mice. J Chromatogr A 2011; 1218:3367-75. [DOI: 10.1016/j.chroma.2010.07.060] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2010] [Revised: 07/19/2010] [Accepted: 07/24/2010] [Indexed: 10/19/2022]
|
23
|
Jones AW, Kugelberg FC, Holmgren A, Ahlner J. Drug poisoning deaths in Sweden show a predominance of ethanol in mono-intoxications, adverse drug-alcohol interactions and poly-drug use. Forensic Sci Int 2010; 206:43-51. [PMID: 20630671 DOI: 10.1016/j.forsciint.2010.06.015] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2010] [Revised: 06/10/2010] [Accepted: 06/13/2010] [Indexed: 11/30/2022]
Abstract
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 < 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 < 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) 0.5mg/L (0.2mg/L), amphetamine (N = 39) 2.0mg/L (1.2mg/L), dextropropoxyphene (N = 33) 3.9 mg/L (2.9 mg/L), dihydro-propiomazine (N = 32) 1.6 mg/L (1.0mg/L) and 7-amino-flunitrazepam (N = 28), 0.4 mg/L (0.3mg/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.
Collapse
Affiliation(s)
- A W Jones
- Department of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, 587 58 Linköping, Sweden.
| | | | | | | |
Collapse
|
24
|
Adverse interaction of warfarin and paracetamol: evidence from a post-mortem study. Eur J Clin Pharmacol 2009; 66:97-103. [PMID: 19779704 DOI: 10.1007/s00228-009-0727-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2009] [Accepted: 09/03/2009] [Indexed: 10/20/2022]
Abstract
PURPOSE The aim of the study was to establish the prevalence and nature of potential adverse drug combinations of warfarin in a large post-mortem toxicology database. The concomitant use of warfarin and non-steroidal anti-inflammatory drugs (NSAIDs) was of interest as these drugs have been associated with internal bleeding both in clinical and post-mortem study settings. Another purpose was to obtain facts related to the questioned safety of warfarin-paracetamol and warfarin-tramadol combinations. METHODS The post-mortem database was searched for a 1-year period. All warfarin-positive cases and cases containing interacting drugs, as defined by the SFINX interaction database (Swedish, Finnish, Interaction X-referencing), were included. For controls, all cases containing paracetamol or tramadol were also included, and for each warfarin-positive case, an age-, sex- and alcohol-matched control case was sourced. The contribution of anticoagulant use to the deaths was evaluated from the death certificates based on medico-legal autopsies. RESULTS In 33% of the 328 warfarin-positive cases, at least one interacting drug was present, and paracetamol was the most abundant, accounting for 49% (n = 53). When paracetamol and warfarin were detected simultaneously, the number of fatal bleeds was 4.6 and 2.7 times higher compared to paracetamol or warfarin use alone respectively. The presence of an NSAID in combination with warfarin was rare, as only six cases were identified. A majority (66%) of the post-mortem blood samples had a warfarin concentration below 0.5 mg/l, and for the rest of the cases, the mean concentration was 0.70 mg/l. CONCLUSIONS This study supports the clinical evidence suggesting that warfarin-paracetamol interactions may create significant life-threatening conditions. It also accentuates the significant role post-mortem database research can have in improving drug safety.
Collapse
|
25
|
Aoyama K, Yoshinari K, Kim HJ, Nagata K, Yamazoe Y. Simultaneous Expression of Plural Forms of Human Cytochrome P450 at Desired Ratios in HepG2 Cells: Adenovirus-mediated Tool for Cytochrome P450 Reconstitution. Drug Metab Pharmacokinet 2009; 24:209-17. [DOI: 10.2133/dmpk.24.209] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
26
|
Musteata FM, de Lannoy I, Gien B, Pawliszyn J. Blood sampling without blood draws for in vivo pharmacokinetic studies in rats. J Pharm Biomed Anal 2008; 47:907-12. [DOI: 10.1016/j.jpba.2008.03.028] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2008] [Revised: 03/20/2008] [Accepted: 03/21/2008] [Indexed: 10/22/2022]
|
27
|
Jones AW, Holmgren A, Kugelberg FC. Concentrations of scheduled prescription drugs in blood of impaired drivers: considerations for interpreting the results. Ther Drug Monit 2007; 29:248-60. [PMID: 17417081 DOI: 10.1097/ftd.0b013e31803d3c04] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
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.
Collapse
Affiliation(s)
- A W Jones
- Department of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Artillerigatan 12, Linköping, Sweden.
| | | | | |
Collapse
|
28
|
Es-haghi A, Zhang X, Musteata FM, Bagheri H, Pawliszyn J. Evaluation of bio-compatible poly(ethylene glycol)-based solid-phase microextraction fiber for in vivo pharmacokinetic studies of diazepam in dogs. Analyst 2007; 132:672-8. [PMID: 17592586 DOI: 10.1039/b701423f] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Solid-phase microextraction probes based on poly(ethylene glycol)/C18-bonded silica were used for in vivo monitoring of drugs from circulating blood of beagles, over a period of 8 h. After sampling, the extracted drugs were subsequently quantified by liquid chromatography coupled with tandem mass spectrometry. External calibrations in whole blood and phosphate-buffered saline were used to correlate the amount of analytes extracted in regard to the total and free concentrations in blood respectively. The probe provided sufficient sensitivity for the drugs in the blood matrix, while the need for drawing blood was eliminated. The limit of detections of the method from whole blood were 1.7, 1.4 and 2.8 ng mL(-1) for the analysis of diazepam, nordiazepam and oxazepam respectively, and the linear range was from 4 ng mL(-1) to 2 microg mL(-1). The method was applied for the monitoring of pharmacokinetic profiles of intravenous administration of diazepam and its two main metabolites in dogs, and the results were compared with profiles determined by conventional methods. This approach offered increased sensitivity and accuracy, short extraction time, and convenient calibration for in vivo sampling for dynamic monitoring.
Collapse
Affiliation(s)
- Ali Es-haghi
- Department of Chemistry, University of Waterloo, Ontario, Canada N2L 3G1
| | | | | | | | | |
Collapse
|
29
|
Abstract
Abstract
Background: We sought to develop a technique with the potential to partly replace current methods of analysis based on blood draws. To achieve this goal, we developed an in vivo microextraction technique that is faster than conventional methods, interferes minimally with the investigated system, minimizes errors associated with sample preparation, and limits exposure to hazardous biological samples.
Methods: Solid-phase microextraction devices based on hydrophilic polypyrrole and polyethylene glycol coatings were used for direct extraction of drugs from the flowing blood of beagle dogs, over a period of 8 h. The drugs extracted on the probes were subsequently quantified by liquid chromatography coupled to tandem mass spectrometry. Two calibration strategies—external and standard on the fiber—were used to correlate the amount extracted with the in vivo concentration.
Results: Diazepam and its metabolites were successfully monitored over the course of a pharmacokinetic study, repeated 3 times on 3 beagles. The fast microextraction technique was validated by comparison with conventional plasma analysis, and a correlation factor of 0.99 was obtained. In addition to total concentrations, the method was useful for determining free drug concentrations.
Conclusions: The proposed technique has several advantages and is suitable for fast clinical analyses. This approach could be used not only for drugs, but for any other endogenous or exogenous compounds.
Collapse
Affiliation(s)
- Florin Marcel Musteata
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada
| | | | | |
Collapse
|
30
|
Jones AW. Driving under the influence of drugs in Sweden with zero concentration limits in blood for controlled substances. TRAFFIC INJURY PREVENTION 2005; 6:317-22. [PMID: 16266940 DOI: 10.1080/15389580500253760] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
OBJECTIVE This article describes the background and implementation in Sweden of zero-concentration limits for controlled drugs in the blood of drivers. Eliminating the need to prove that a person's ability to drive safely was impaired by drugs has greatly simplified the prosecution case, which now rests primarily on the forensic toxicology report. Driving under the influence of a prescription drug listed as a controlled substance is exempt from the zero-limit law provided the medication was being used in accordance with a physician's direction and the person was not considered unfit to drive. METHODS The prevalence of driving under the influence of drugs (DUID) in Sweden was evaluated from police reports with the main focus on the toxicological findings. A large case series of DUID suspects was compared before and after introducing zero concentration limits in blood for controlled substances on July 1, 1999. The spectrum of drugs used by typical offenders and the concentrations of various licit and illicit substances in blood were evaluated and compared. RESULTS Immediately after the zero-limit law came into force, the number of cases of DUID submitted by the police for toxicological analysis increased sharply and is currently ten-fold higher than before the new legislation. Statistics show that about 85% of all blood samples sent for toxicological analysis have one or more banned substances present. Amphetamine is by far the leading drug of abuse in Sweden and was identified in about 50-60% of all DUID suspects either alone or together with other controlled substances. The next most frequently encountered illicit drug was tetrahydrocannabinol (THC), with positive findings in about 20-25% of cases. Various prescription drugs, mainly sedative-hypnotics like diazepam and flunitrazepam, were also highly prevalent and these occurred mostly together with illicit substances. Opiates, such as 6-acetyl morphine and morphine, the metabolites of heroin, were high on the list of substances identified. Most DUID suspects in Sweden were men (85%) who were poly-drug users combining illicit substances, like amphetamine and/or cannabis, with a prescription medication such as various benzodiazepines. CONCLUSIONS Sweden's zero-concentration limit has done nothing to reduce DUID or deter the typical offender because recidivism is high in this population of individuals (40-50%). Indeed, many traffic delinquents in Sweden are criminal elements in society with previous convictions for drunk and/or drugged driving as well as other offenses. The spectrum of drugs identified in blood samples from DUID suspects has not changed much since the zero-limit law was introduced.
Collapse
Affiliation(s)
- Alan Wayne Jones
- Department of Forensic Toxicology, University Hospital, Linköping, Sweden.
| |
Collapse
|
31
|
Jones AW. Driving under the influence of chlormethiazole. Forensic Sci Int 2005; 153:213-7. [PMID: 15975749 DOI: 10.1016/j.forsciint.2005.05.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2005] [Revised: 04/28/2005] [Accepted: 05/07/2005] [Indexed: 11/30/2022]
Abstract
This article describes a case of driving under the influence of the sedative-hypnotic-anticonvulsant drug chlormethiazole. The suspect, who was a physician, was driving dangerously on a busy highway and caused a traffic collision. When apprehended by the police, the man had bloodshot and glazed eyes and pupil size was enlarged. He could not answer the questions properly and his gait was unsteady. A roadside breath-alcohol screening test was positive but an evidential breath-alcohol test conducted about one hour later was below the legal limit for driving of 0.10 mg/L (10 microg/100 mL or 0.021 g/210 L). Because of the special circumstances of the traffic crash and the man's appearance and behaviour, the police suspected that drugs other than alcohol were involved and obtained a venous blood sample for toxicological analysis. The blood contained 0.23 mg/g alcohol, which is above the legal limit for driving in Sweden 0.20 mg/g (20 mg/100 mL or 0.020 g/100 mL), and codeine was also present at a therapeutic concentration of 0.02 mg/L. The conflict between the clinical signs of impairment and the toxicology report prompted a reanalysis of the blood sample with major focus on sedative-hypnotic drugs. Analysis by capillary GC-NPD identified chlormethiazole at a concentration of 5mg/L, the highest so far encountered in traffic cases in Sweden. In 13 other impaired driving cases over 10 years the mean (median) and range of concentrations of chlormethiazole were 1.6 mg/L (1.6 mg/L) and 0.3-3.3 mg/L. This case report underscores the need to consider clinical observations and the person's behaviour in relation to the toxicology report when interpreting and testifying in drug-impaired driving cases.
Collapse
Affiliation(s)
- Alan Wayne Jones
- Department of Forensic Toxicology, University Hospital, 581 85 Linköping, Sweden.
| |
Collapse
|
32
|
Affiliation(s)
- T A Brettell
- Office of Forensic Sciences, New Jersey State Police, New Jersey Forensic Science and Technology Complex, 1200 Negron Road, Horizon Center, Hamilton, New Jersey 08691, USA
| | | | | |
Collapse
|
33
|
|
34
|
Jones AW, Holmgren A, Holmgren P. High concentrations of diazepam and nordiazepam in blood of impaired drivers: association with age, gender and spectrum of other drugs present. Forensic Sci Int 2004; 146:1-7. [PMID: 15485715 DOI: 10.1016/j.forsciint.2004.05.020] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2004] [Revised: 05/25/2004] [Accepted: 05/25/2004] [Indexed: 11/22/2022]
Abstract
A zero-concentration limit for controlled scheduled drugs in the blood of motorists was introduced in Sweden in 1999 and the annual number of arrests for driving under the influence of drugs (DUID) has since increased eight-fold. However, for prescription drugs that might cause impairment (e.g. benzodiazepines) additional proof is needed to justify prosecution, such as whether the medication was being misused. Over a 2-year period, we found 94 cases of DUID in which the concentrations of diazepam in blood was 1.1 microg/g or more. Diazepam (D) and nordiazepam (ND) were determined in whole blood by capillary gas chromatography with a limit of quantitation of 0.05 microg/g for each compound. The mean (median) and maximum concentrations of D were 2.0 microg/g (1.7 microg/g) and 7.8 microg/g and the corresponding ND concentrations were 1.5 microg/g (1.0 microg/g) and 7.6 microg/g, respectively. The concentration of D in blood exceeded 2 microg/g in 21% of cases and was over 3.0 microg/g in 11% of cases. D and ND were the only drugs present in eight cases (seven men and one women) and in another five cases ethanol was present at concentrations ranging from 0.81 to 1.98 mg/g. Polydrug use was very common in these DUID suspects and D and ND coexisted with amphetamine in 20% of cases, tetrahydrocannabinol in 18% of cases and with both these illicit drugs in 12% of cases. The next most prevalent drug combination was D, ND and morphine (mostly derived from heroin), seen in 13% of cases. Other psychoactive prescription drugs were identified in blood including alprazolam, flunitrazepam, oxazepam, zolpidem and zopiclone. This case series of DUID suspects demonstrate the high frequency of polydrug use showing preference for illicit drugs like amphetamine, cannabis and heroin, in that order. Furthermore, Swedish traffic delinquents frequently overdose with prescription drugs as exemplified here by unusually high concentrations of D and its active metabolite ND.
Collapse
Affiliation(s)
- A W Jones
- Department of Forensic Toxicology, University Hospital, 58185 Linköping, Sweden.
| | | | | |
Collapse
|