[Serum benzodiazepine research by the immunoenzymatic method in emergency toxicology: test interpretation aids]

The analyst in toxicology is daily confronted with blood benzodiazepine research. The sensitivity of the immunoenzyme technique initially designed for urine testing has been improved. Nevertheless some discrepancies persist between clinical and biological observation. This work based on kinetic characteristics of benzodiazepine and analytical sensitivity indicates drug quantities which should be ingested to have a positive test. These quantities are computed for a man and a woman of average weight of 70 kg and 50 kg and for a child weighing 13 kg (about three years old). They are then compared to quantities usually considered as toxic. Nevertheless, these values have to be adapted on a case to case basis. As a general observation, analytical sensitivities for benzodiazepine are variable but the immunoenzyme technique ensures a good covering of real toxic quantities of the drug. Flunitrazepam is the one which has the worst covering probability.