MEPROBAMATE OVERDOSAGE - A CONTINUING PROBLEM - SENSITIVE GC-MS QUANTITATION AFTER SOLID-PHASE EXTRACTION IN 19 FATAL CASES

We describe a simple method for the urinary identification and blood q uantitation of meprobamate suitable for any toxicological laboratory. After urinary screening using GC-MS technology, quantitation is perfor med by GC-MS in the selected-ion monitoring mode. Isolation of the dru g is achieved by solid phase extraction on a C-18 cartridge. A specifi c elution is obtained by three volumes of acetone:triethylamine (99:1 v/v). Lidocaine is used as internal standard. RSDs (%) of the within-d ay and between-day precision studies are always less than 7.2 on the e ntire range of calibration. Linearity is inspected using an analysis o f variance ANOVA. Homogeneity of the variances is tested using Hartley 's test. Weighted linear regression is then computed. Limits of detect ion and quantification are given by an analysis of the blanks. The pre sent method was applied in our laboratory over a period of 1 year. Mep robamate appeared as a drug which still has a significant frequency (5 .5%) and is the most frequently involved in fatal pharmaceutical overd oses (15.3%). Post mortem concentrations ranged from 41 to 397 mg/l (m ean=182) and are compared to those of the literature. Copyright (C) 19 97 Elsevier Science Ireland Ltd.