The use of anti-depressants and benzodiazepines in the perpetrators and victims of accidents.

The objective of this study was to determine whether there is a greater incidence of psychotropic drugs in the blood of those 'responsible' for an accident compared with those not 'responsible' for an accident. Blood samples were taken from people involved in accidents presenting at the accident and emergency departments of two teaching hospitals over a five-month period and analysed for the presence of alcohol, tricyclic anti-depressants (TCAs) and benzodiazepines (BZs). Details of the accident were used to produce a test group (accidents where a drug may have contributed) and a control group (accidents where the presence of a drug could not have been a factor). In total, 229 samples were collected. The only criterion for inclusion in the study was that the accident was of sufficient severity to merit the routine taking of a blood sample, in which case an additional amount was taken for the purposes of this investigation. In all, 63 samples (27.5%) were positive for at least one of alcohol, TCA or BZ. Of the accidents represented by these samples, 48 could have been caused by the presence of the drug (responsible group) and 15 could not (not responsible group). There was a significantly greater representation of TCAs and BZs in the blood taken from the responsible group compared with the not responsible group (P < 0.0045).