The records for Coroner's Inquests in one district during a 6 year period were examined retrospectively to establish the number and nature of deaths which were due to errors in the prescription or administration of medicines, and those due to adverse drug reactions. The district has a population of 1.19 million (1991), and a total of 3277 inquests were opened during the period 1986-1991. Ten of the deaths were identified as due to errors of prescribing or giving drugs. During the same period, 36 deaths were caused by adverse drug reactions. These 46 deaths made up approximately one in 2000 of all deaths during the study period. About a fifth of deaths related to prescribing and administering drugs are due to errors and may be more easily preventable than deaths due to adverse reactions.