[Occurrence of diazepam in blood samples of drivers under the influence of alcohol (author's transl)].

Diazepam was determined by radioimmunoassay and gas chromatography in 2050 unselected blood or serum specimens of subjects, who were sus,ected of driving under the influence of alcohol in the years 1974 and 1976. A "cut-off" limit of 20 ng/ml was selected. Diazepam was found in 46 samples corresponding to 2.24%, 27 samples (1.3%) exhibited concentrations of 20--100 ng/ml, 14 samples (0.7%) of 100--500 ng/ml, 1 sample (0.05%) of 500--1000 ng/ml and 4 samples (0.2%, as related to the total of 2050 samples) of more than 1000 ng/ml. Furthermore, 44 blood specimens of subjects were analyzed, who had claimed diazepam intake before the blood sample was withdrawn. Diazepam was found in 27 cases corresponding to 61%. Finally, blood specimens of 219 unselected inpatients of a surgical ward were investigated; 59 of these (27%) were found to be diazepam-positive.