Quantification of Loperamide by Gas Chromatography Mass Spectrometry.

Due to reported pharmacological activity similar to classical opioids at supratherapeutic concentrations, abuse of the anti-diarrheal medication loperamide (Imodium AD™) has become a target in the opioid epidemic. While this phenomenon is not new, published quantitative analytical methods use liquid chromatography tandem mass spectrometry. Described here is an 11 min method for quantification of loperamide in postmortem whole blood by gas chromatography mass spectrometry. Validation studies performed followed SWGTOX guidelines and included: accuracy, specificity, limit of detection (LOD), regression model analysis, stability, and matrix recovery enhancement and/or suppression. The accuracy study consisted of inter-day, intra-day, reproducibility and dilution integrity experiments. Inter-day and intra-day accuracy, precision and coefficient of variation (CV) were measured; normalized results were 1.05 ± 0.09 with 8.87% CV (n = 36) and 1.03 ± 0.09 with 8.53% CV (n = 27), respectively. Reproducibility was evaluated through standard addition with an observed CV of 10.84% (n = 10). Dilution integrity (2× and 4×) resulted in 0.94 ± 0.13 with a CV of 13.9% (n = 5). No interference was observed through analyses of the internal standard (loperamide-d6), endogenous compounds (10 blank matrices) or 60 commonly encountered analytes. The LOD/decision point was 100 ng/mL (CV 8.40%). A linear calibration model was established from 100 to 1,000 ng/mL. Stability was examined; observed analyte-to-internal standard response resulted in 6.59% CV. Recovery was determined for loperamide and loperamide-d6 (31% and 36%, respectively). Neither matrix suppression nor enhancement was observed with loperamide at 750 ng/mL and loperamide-d6 at 300 ng/mL (-6.5% and -4.2%); however, some suppression was exhibited at lower concentrations (-39.8%). The designed method was determined to be sufficient for the analysis of loperamide-related death cases in Alabama (n = 8) and offers postmortem toxicology laboratories an alternative approach that is both highly selective and specific.

High urine ethanol and negative blood and vitreous ethanol in a diabetic woman: a case report, retrospective case survey, and review of the literature.

Several studies have shown that ethanol can be produced in urine infected with yeast or bacteria in vitro. We present the unusual case of a diabetic woman in whom ethanol was produced in her urine in vivo. The decedent was a 19-year-old woman who was noncompliant with her diabetes treatment. She presented to a local hospital in severe diabetic ketoacidosis and died shortly thereafter. Upon arrival at the hospital, a blood glucose of 553 mg/dL was detected. A urinalysis was positive for ketones (> 80 mg/dL), glucose (> 1000 mg/dL), and large budding yeast forms. A drug screen performed on the urine was positive for ethanol. At the coroner/medical examiner office, an autopsy was negative for significant anatomic findings. Toxicology analysis revealed a urine ethanol level 0.32 g/dL, although no ethanol was detected in blood or vitreous samples. A urine gram stain and culture identified Candida glabrata. A retrospective case review of all deaths related to diabetes examined at the coroner/medical examiner office from 1986 to 2003 did not reveal other cases with similar findings. This case of a noncompliant, juvenile-diabetic woman illustrates a rare finding of apparent in vivo glucose fermentation by C. glabrata to form ethanol in the urine. This case also highlights a potential difficulty in toxicologic analysis and interpretation using urine only.

Polydrug fatality involving metaxalone.

A 29-year old female with a history of depression was found dead in a hotel room. The death scene investigation found empty pill bottles and an empty liter bottle of wine. Metaxalone, a centrally acting muscle relaxant, along with citalopram, ethanol, and chlorpheniramine were identified in the postmortem samples and quantitated by gas chromatography-mass spectrometry. The concentration of metaxalone in femoral vein blood was 39 mg/L. The heart blood concentration was 54 mg/L. Femoral vein blood concentrations of citalopram and chlorpheniramine were 0.77 mg/L and 0.04 mg/L, respectively. Ethanol levels were 0.13 g/dL in vitreous and 0.08 g/dL in heart blood. Other tissue samples were also analyzed. The authors consider the metaxalone concentrations toxic and potentially fatal. The citalopram concentrations were lower than those reported in fatal cases for this drug alone. Death was ascribed to polydrug abuse/overdose with metaxalone a major contributor. This represents the first reported case to our knowledge in which a metaxalone overdose significantly contributed to death.