Concentrations of zolpidem and zopiclone in venous blood samples from impaired drivers compared with femoral blood from forensic autopsies

The concentrations of zolpidem and zopiclone were determined in peripheral blood samples in two forensic materials collected over a 10-year period (2001-2010). The z-hypnotics were determined in venous blood from living subjects (impaired drivers) and in femoral blood from deceased persons (forensic autopsies), with the latter classified as intoxication or other causes of death. The z-hypnotics were determined in blood by capillary column gas chromatography (GC) with a nitrogen-phosphorous (N-P) detector after solvent extraction with n-butyl acetate. The analytical limit of quantitation (LOQ) was 0.02mg/L for zopiclone and 0.05mg/L for zolpidem and these have remained unchanged throughout the study. When death was attributed to drug intoxication (N=918), the median concentration of zopiclone in blood was 0.20mg/L compared with 0.06mg/L for other causes of death (N=1215) and 0.07mg/L in traffic offenders (N=691) (p<0.001). Likewise, a higher median concentration (0.30mg/L) was found in intoxication deaths involving zolpidem (N=357) compared with 0.13mg/L for other causes of death (N=397) or 0.19mg/L in impaired drivers (N=837) (p<0.001). Median concentration in blood of both z-hypnotics were appreciably higher in intoxication deaths when no other substances were identified; 0 70mg/L (N=12) for zopiclone and 1.35mg/L (N=12) for zolpidem. The median concentrations of z-hypnotics in blood decreased as the number of co-ingested substances increased for intoxication deaths but not other causes of death. The most prevalent co-ingested substances were ethanol in autopsy cases and diazepam in the motorists. This large compilation of forensic cases should prove useful when toxicologists are required to interpret concentrations of z-hypnotics in blood samples in relation to cause of death.     

Windows of detection of zolpidem in urine and hair: application to two drug facilitated sexual assaults

A LC-MS/MS method for the detection of zolpidem in hair was developed to detect this drug after a single dose in possible drug facilitated sexual assaults. To determine the window of detection of zolpidem in both urine and hair, three volunteers received a 10 mg dose. Urine specimens were collected each 12 h for 144 h. Hair was sampled 3-5 weeks after exposure. Hair and urine extracts were separated on a Xterra MS C18 column using a gradient of acetonitrile and formate buffer. For each compound, detection was related to two daughter ions. Zolpidem was detected for up to 60 h in urine with peak concentrations obtained at 12 h. A single exposure to zolpidem was detected in hair at concentrations ranging from 1.8 to 9.8 pg/mg. Hair analysis was applied to two possible criminal cases. In the first case, zolpidem tested positive in the corresponding hair segment at 4.4 pg/mg. In the other case, zolpidem was detected in all the segments analyzed, demonstrating likely previous drug use in addition to recent exposure associated with a positive blood result.     

Fatal intoxication involving 2-methyl AP-237

Novel synthetic opioids contribute considerably to the opioid epidemic, especially with the frequent emergence of structurally similar compounds. This case report describes a fatal intoxication involving 2-methyl AP-237. A 54-year-old Caucasian male was found deceased from an apparent drug overdose. A plastic container labeled “2MAP” and a cut straw were found in the decedent's backpack at the scene. A white substance found in the container tested positive for fentanyl by field testing. According to his medical history, the decedent was treated for a drug overdose 3 years prior to his death. With no diagnostic findings at autopsy, the case was submitted for toxicological analysis. An unknown substance was detected in peripheral blood and urine using gas chromatography with nitrogen phosphorous detection (GC-NPD). Further testing was conducted using gas chromatography–mass spectrometry (GC–MS) and liquid chromatography-quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS) which confirmed the presence of 2-methyl AP-237 and potential metabolites in blood and urine. Quantitation by GC-NPD revealed concentrations of 2-methyl AP-237 in blood and urine at 480 ng/mL and 4200 ng/mL, respectively. The toxicological analysis also identified and quantitated alprazolam in the blood at 55 ng/mL. Additionally, the metabolism of 2-methyl AP-237 was investigated and three hydroxylated metabolites were identified in peripheral blood and urine. Limited literature is available for the detection and quantitation of 2-methyl AP-237 in postmortem specimens. Given the toxicological findings with unremarkable autopsy findings, this case is an example of a fatal intoxication involving 2-methyl AP-237.     

Zolpidem and driving impairment

Zolpidem, a non-benzodiazepine hypnotic, was identified in the blood of 29 subjects arrested for impaired driving. Zolpidem concentrations ranged from 0.05 to 1.4 mg/L (mean 0.29 mg/L, median 0.19 mg/L). In the subjects whose cases we reviewed where zolpidem was present with other drugs and/or alcohol, symptoms reported were generally those of CNS depression. Symptoms included slow movements and reactions, slow and slurred speech, poor coordination, lack of balance, flaccid muscle tone, and horizontal and vertical gaze nystagmus. In five separate cases, where zolpidem was the only drug detected (0.08-1.40 mg/L, mean 0.65 mg/L, median 0.47 mg/L), signs of impairment included slow and slurred speech, slow reflexes, disorientation, lack of balance and coordination, and "blacking out." Although no quantitative relationship between blood concentrations and degree of driving impairment is currently possible, it is reasonable to conclude that because of its specific activity as a sleep inducer, blood concentrations consistent with therapeutic doses of zolpidem have the potential to affect driving in a negative way, and that concentrations above the normal therapeutic range would further impair a person's level of consciousness and driving ability.     

Toxicology and characteristics of deaths involving zolpidem in new South wales, australia 2001-2010*

Abstract: All cases presenting to the New South Wales Department of Forensic Medicine between January 1, 2001 and September 31, 2010 in which zolpidem was detected, were retrieved. A total of 91 cases were identified. The mean age was 49.4 years, 65.9% were male, and 61.5% were suicides. Zolpidem was a factor contributing to death in 35 (37.3%) cases, of which 31 (34.1%) involved zolpidem toxicity. The median blood zolpidem concentration was 0.20 mg/L (range 0.05–3.50 mg/L), with no significant gender difference. Drug toxicity cases involving zolpidem had significantly higher median blood zolpidem concentrations than other cases (0.50 vs. 0.10 mg/L). In 83.5% of cases, psychoactive substances other than zolpidem were detected, most commonly antidepressants (46.2%), benzodiazepines (35.2%), opioids (26.4%), and alcohol (39.6%). In summary, zolpidem was a factor contributing to death in a large proportion of cases, predominately involving drug toxicity and suicide.     

The interpretation of cocaine and benzoylecgonine concentrations in postmortem cases.

This study examined cocaine and benzoylecgonine concentrations in 100 consecutive deaths where either compound was identified in blood or urine specimens to determine whether any relationship between these concentrations and cause of death can be found. Forty-seven of the 100 cases were deaths attributed to cocaine, narcotic or combined cocaine and narcotic intoxication. There were 13 cases of cocaine intoxication where no psychoactive substance other than ethanol was detected. The mean cocaine concentration in these deaths was 908 ng/ml; three cases had cocaine concentrations greater than 2000 ng/ml, while the other ten cases had cocaine concentrations less than or equal to 700 ng/ml. The mean cocaine concentration in non-cocaine deaths where no psychoactive substance other than ethanol was detected was 146 ng/ml. This difference was not statistically significant. However, the average blood benzoylecgonine concentration in the 13 cocaine deaths was significantly higher than in the 19 non-cocaine deaths. A review of combined cocaine and narcotic deaths suggest that the narcotic is the main causative agent in these deaths.     

Assessment of the acuteness of heroin deaths from the analysis of multiple blood specimens.

Data was compiled from 126 morphine-involved cases investigated by the Office of the Chief Medical Examiner, State of Maryland, USA. An investigation was conducted into whether comparison of morphine concentrations from a central and peripheral site could be used to determine whether a morphine death was acute or delayed. Fifty cases were identified as 'acute' because the urine free morphine concentration by radioimmunoassay (RIA) was less than 25 ng/mL; 76 cases were classified as 'random' because they had a urine morphine concentration greater than 25 ng/mL by RIA. The average heart blood to peripheral blood morphine concentration ratio in the acute deaths was 1.40. The average heart blood to peripheral blood morphine concentration ratio in the random deaths was 1.18. Because there was considerable overlap between the two groups of data, the authors conclude that it was not possible to predict 'acute' opiate intoxication deaths versus 'delayed' deaths when the only information available is heart and peripheral blood free morphine concentrations.     

Tramadol (Ultram) concentrations in death investigation and impaired driving cases and their significance

We reviewed a series of 66 deaths in Washington State between 1995-2000 in which tramadol (Ultram and Ultracet, Ortho-McNeil) was detected in the decedent's blood, in order to assess the role tramadol was determined to have played. Additionally, we reviewed a series of 83 impaired driving cases in which tramadol was detected in order to establish a non-lethal blood tramadol concentration reference range. In both populations, tramadol was consistently found together with other analgesic, muscle relaxant, and CNS depressant drugs. Death was rarely attributable to tramadol alone. However, tramadol may be a significant contributor to lethal intoxication when taken in excess with other drugs, via the potential interaction with serotonergic antidepressant medications, as well as the potential for increased CNS depression. Although the incidence of tramadol detection has increased consistently over the last eight years, there is no evidence of a corresponding increase in the number of cases in which death was attributed solely to tramadol. Blood drug concentrations in many deaths exceeded the therapeutic serum range of 0.28-0.61 mg/L; however, the concentrations overlapped almost completely with the range identified in living subjects arrested for impaired driving. These findings suggest caution in the interpretation of blood tramadol concentrations outside of the recognized therapeutic range. It also suggests that the drug, even when used in moderate excess, is not a principle cause of death in suicidal or accidental deaths.     

Acute intoxication with guaifenesin, diphenhydramine, and chlorpheniramine.

Mixed drug reactions are frequently encountered in emergency department overdose cases and also in fatal intoxications. Assessment of the relative contribution of each drug in producing adverse effects is often compounded by lack of case history and the paucity of cases reported in the literature. This report describes a fatal intoxication with three common over-the-counter medications: guaifenesin, diphenhydramine, and chlorpheniramine. A 48-year-old woman was found dead in the attic bedroom of her residence. Specimens obtained at autopsy for toxicologic analysis included heart blood, urine, bile, gastric contents, vitreous humor, and cerebrospinal fluid. The over-the-counter drugs were identified and quantitated by acid/neutral or basic liquid-liquid extraction followed by gas chromatographic analysis with nitrogen phosphorus detection. Concentrations of guaifenesin, diphenhydramine, and chlorpheniramine detected in the heart blood were 27.4, 8.8, and 0.2 mg/L, respectively. The cause of death was determined to be acute intoxication by the combined effects of guaifenesin, diphenhydramine, and chlorpheniramine, and the manner of death was determined to be suicide. To our knowledge, the blood guaifenesin concentration in this case is the highest reported concentration to date associated with an acute intoxication.     

Oral abuse of fentanyl patches (Duragesic): seven case reports

In order to increase the understanding regarding the oral abuse and potential toxicity of fentanyl patches seven cases were identified over a 3-year period where fentanyl, either alone or in combination with other factors, contributed to death following the oral abuse of Duragesic patches. The decedents comprised three females and four males with ages ranging from 20 to 51 years. Postmortem blood fentanyl concentrations were determined in all cases and ranged from 7 to 97 ng/mL. Two deaths were classified as a fentanyl overdose, three deaths were classified as a fentanyl and ethanol overdose, one death was considered a mixed drug intoxication and the remaining death was determined to be a combination of fentanyl and medical causes. These cases represent the largest reported series of deaths following the oral administration of transdermal fentanyl patches and provide detailed information on the potential for the abuse of transdermal Duragesic patches via this route. The postmortem blood fentanyl concentrations detected for each of the decedents demonstrate the potentially fatal blood concentrations that can arise after this relatively rare route of administration.     

Intoxication due to 1,4-butanediol

We report a case of intoxication resulting from the ingestion of a liquid, sold in the illicit market as "liquid ecstasy," which was found to contain 1,4-butanediol, a metabolic precursor of gamma-hydroxybutiric acid (GHB). Identification of the substance in the liquid was performed by gas chromatography-mass spectrometry (GC-MS).The toxicological analysis of blood, urine and gastric content of the victim was performed by immunoassay and gas chromatography with nitrogen-phosphorus detection as screening techniques and by means of GC-MS for confirmation and quantitation of 1,4-butanediol and GHB. The following drug concentrations were found: 82 microg/ml (blood), 401 microg/ml (urine) and 7.4 microg/ml (gastric content) for 1,4-butanediol and 103 microg/ml (blood), 430.0 microg/ml (urine) for GHB. In addition to these, other drugs detected and their blood concentration found in this case were methylenedioxymethylamphetamine (MDMA) 0.23 microg/ml and its metabolite methylenedioxyphenylamphetamine (MDA) 0.10 microg/ml. In the urine, a concentration of 0.10 microg/ml of benzoylecgonine was also found.     

Post-mortem cases involving amphetamine-based drugs in The Netherlands. Comparison with driving under the influence cases

In this study we reviewed the post-mortem cases in the years 1999-2004 that were presented at the Netherlands Forensic Institute. The concentrations of amphetamine-based drugs in femoral blood from cases of suspected unnatural death were compared with concentrations in whole blood from non-fatal cases of driving under the influence (DUI cases) and with literature. Furthermore, the combinations with other drugs and/or alcohol were investigated. Amphetamine-based drugs were present in 70 post-mortem cases and 467 DUI cases. The most detected amphetamine-based drug was MDMA, followed by amphetamine. The presence of MDA could usually be explained by metabolism of MDMA. Methamphetamine and MDEA were rarely present. Frequently, the amphetamine-based drugs were taken in combination with alcohol and/or other non-amphetamine-based drugs such as cocaine or cannabinoids. The 70 post-mortem cases were divided into 38 amphetamine-based drug caused (i.e. the amphetamine-based drug directly caused or contributed to the death) and 32 amphetamine-based drug related deaths (i.e. death was not directly caused by the amphetamine-based drug). In the latter category, other (poly)drug intoxications and death by violence or drowning were the most frequent causes of death. In 30 cases, MDMA caused death directly. The range in blood concentrations of MDMA in these cases was substantial, i.e. 0.41-84 mg/L with a median concentration of 3.7 mg/L (n=30). MDMA blood concentrations in the MDMA related deaths (n=20) and in the DUI cases (n=360) varied up to 3.7 and 4.0 mg/L, respectively. Seven victims died from the direct effects of amphetamine; the blood concentration of amphetamine ranged from 0.24 to 11.3 mg/L, with a median concentration of 1.7 mg/L (n=7). The median concentrations of amphetamine in the amphetamine related deaths (n=13) and the DUI cases (n=208) were much lower, i.e. 0.28 and 0.22 mg/L, respectively. Amphetamine blood concentrations up to 6.0 and 2.3 mg/L were seen in the drug related deaths and DUI cases, respectively. The most frequently encountered amphetamine-based drugs in the investigated deaths were MDMA and amphetamine. The majority of MDMA- and amphetamine-caused deaths, i.e. 90% of these deaths, occurred with blood concentrations above 1.5 and 0.80 mg/L, respectively. MDMA and amphetamine blood concentrations in drug related deaths and DUI cases, however, overlap the range of fatal concentrations. Therefore, MDMA or amphetamine concentrations should never be used alone to establish the cause of death.     

A review of methadone deaths in Jefferson County,Alabama

Interpretation of the concentration of a drug is more difficult when a combination of drugs is present in a decedent's blood. An increase in deaths resulting from co-intoxication with methadone and a benzodiazepine led the authors to perform a retrospective study of cases examined at the Jefferson County Coroner/Medical Examiner Office. They found 101 deaths wherein methadone was detected in the blood. Based on the drugs detected in the blood, these 101 cases were grouped into four categories: (1) pure methadone intoxication, (2) intoxication with methadone and benzodiazepine, (3) intoxication with methadone and other drugs excluding benzodiazepine, and (4) intoxication with methadone, benzodiazepines, and other drugs. Methadone was the sole intoxicant in 15 cases, with a mean concentration of 0.27 mg/L. Benzodiazepines were the most frequently detected co-intoxicant (60 of 101 cases). Benzodiazepine was the only co-intoxicant in 30 cases, and the mean methadone concentration in those 30 cases was 0.599 mg/L. Higher levels of methadone may occur in acute intoxication with methadone and benzodiazepine because benzodiazepines compete with methadone for methadone receptors. Higher levels of methadone may occur with chronic abuse of methadone and benzodiazepines because over time, benzodiazepines inhibit the hepatic enzymes that metabolize methadone.     

Fatal tolperisone poisoning: autopsy and toxicology findings in three suicide cases

Tolperisone (Mydocalm) is a centrally acting muscle relaxant with few sedative side effects that is used for the treatment of chronic pain conditions. We describe three cases of suicidal tolperisone poisoning in three healthy young subjects in the years 2006, 2008 and 2009. In all cases, macroscopic and microscopic autopsy findings did not reveal the cause of death. Systematic toxicological analysis (STA) including immunological tests, screening for volatile substances and blood, urine and gastric content screening by GC-MS and HPLC-DAD demonstrated the presence of tolperisone in all cases. In addition to tolperisone, only the analgesics paracetamol (acetaminophen), ibuprofen and naproxen could be detected. The blood ethanol concentrations were all lower than 0.10 g/kg. Tolperisone was extracted by liquid-liquid extraction using n-chlorobutane as the extraction solvent. The quantification was performed by GC-NPD analysis of blood, urine and gastric content. Tolperisone concentrations of 7.0 mg/l, 14 mg/l and 19 mg/l were found in the blood of the deceased. In the absence of other autopsy findings, the deaths in these three cases were finally explained as a result of lethal tolperisone ingestion. To the best of our knowledge, these three cases are the first reported cases of suicidal tolperisone poisonings.     

Phencyclidine: a 5-year retrospective review from the New York City Medical Examiner's Office

We report here a 5-year retrospective review of autopsy cases from the New York City Medical Examiner's Office that demonstrated phencyclidine (PCP) in the blood. There were a total of 138 cases. There were 52 deaths because of mixed drug intoxication: the blood PCP concentrations in these cases ranged from <1 to 598 ng/mL. There were 80 violent deaths in which PCP was quantified in the blood but was unrelated to the cause of death. There were five nonviolent deaths in which PCP exclusively was detected. In four of these, there were preexisting medical conditions that could also have contributed to death. In these, the highest PCP concentration was 361.3 ng/mL, a concentration lower than seven of the individuals in our violent death category. This suggests that lower concentrations may be fatal with comorbid conditions.     

Is urine a suitable material for the preliminary screening of drugs in autopsy cases?

This paper reports a survey of drug screening in the urine specimens of 45 autopsy cases whose livers contained medicinal substances. The extractions were carried out by a solid phase/liquid technique and the analyses by thin-layer chromatography. Nine compounds out of 43 actually present in the liver were not detectable in the urine; eight cases with high drug concentrations in the liver and also in the blood would have evaded the intoxication suspicion had the urine been used as the only material for the chemical survey. On the basis of these data we advocate that the preliminary drug screening of medical-examiner cases not be carried out on urine alone.     

Drug deposition in adipose tissue and skin: evidence for an alternative source of positive sweat patch tests

In a series of licit and illicit drug-related deaths, qualitative and quantitative analyses on extracts of adipose tissue and skin were performed by GC/MS. In all cases, the adipose tissue was found to contain drugs at concentrations lower than, approximately equal to, or even greater than the concentrations of the same analytes found in the blood, which may reflect a consequence of long-term chronic exposure, or acute intoxication, or some combination of both. Approximately one cubic inch of skin with adipose tissue was removed from the mid to lower abdominal region adjacent to the midline incision during autopsy. The drugs were recovered from the specimens following incubation and alkaline, acidic, and alkaline chloroform back extraction of one to three grams of tissue. Deuterated analogs of the analytes were added to the matrix at the beginning of the incubation period. Cocaine and free morphine (from heroin) were readily identified in several cases. The presence of these illicit drugs in adipose tissue raises significant forensic questions, especially the use of 'sweat patches' to monitor recent cocaine or heroin use in chronic drug users.