A prospective multicentre study of all acute poisonings among adults admitted to hospital (n = 1145) or dying outside hospital (n = 67) in Oslo was performed during 1980. Of the 1212 episodes, 98.3% were self-poisonings, giving an annual incidence of 2.8 per 1000 inhabitants (0/00), 3.1 0/00 in males and 2.6 0/00 in females. The main toxic agents among the self-poisoned patients were ethanol (19.7%), benzodiazepines (17.8%), opiates (14.9%), neuroleptics (10.4%) and antidepressants (9.3%). In 58.9% of the episodes more than one toxic agent was taken. Abuse among the self-poisoned patients was significantly (p less than 0.005) more common among males than females (64.2 v. 34.5%). The rate of suicide attempts was significantly (p less than 0.005) higher among females than males (20.2 v. 12.9%), females showing increasing rate with age. However, when excluding abusers the rate of suicide attempts was similar in both sexes (27.6 v. 25.0%). Compared to a reference population self-poisonings were most common in the lower middle and the lowest social classes. Patients in these social classes, however, showed a lower rate of suicide attempts than those in the two highest social classes. Overall mortality was 6.0% (n = 73), but 91.8% of all deaths occurred outside hospital indicating the importance of including these figures when self-poisonings are studied.