[Human toxicokinetic of hexobarbital after acute multi-drug intoxication]

A 33-year-old man was hospitalized unconscious on suspicion of acute diazepam and hexobarbital intoxication, a barbiturate not marketed in France. Its quantification was developed by gas chromatography coupled with mass spectrometry detection and validated on one-hundred microL of plasma extracted by a liquid/liquid method. Hexobarbital and diazepam concentrations in initial plasma samples were at toxic levels, respectively 15 900 ng/mL and 13 800 ng/mL. Hexobarbital toxicokinetic was studied during 175 h and analysed with a non-compartmental model. Half-life value of 61,8 h was found, being much longer than already published hexobarbital half-lives (between 3.2 h and 6.9 h). The reasons of this long half-life were discussed according to metabolism and pharmacogenetic.