The concept of drug automatism.

The drug-automatism hypothesis implies a medication-induced absence of intentionality for self-poisoning and a relative amnesia for serial or single overdosage. Controversy stems from problems encountered in the formulation and verfication of the hypothesis. The author reviews the literature, presents a case associated with a proprietary sleeping preparation, and discusses psychopharmacological and psychophysiological elements in the mechanism of drug automatism and its differential diagnosis.