Acute carbon tetrachloride poisoning in 19 patients was confirmed by means of laboratory analysis of blood specimens. The whole-blood carbon tetrachloride concentrations ranged from 0.1-31.5 mg/l. Vomiting (11 patients), abdominal pain (5), diarrhoea (4), and coma/drowsiness (6) were the commonest symptoms and signs. Out of 13 patients treated with intravenous acetylcysteine 7 showed mild hepatic damage, 1 had moderate hepatic damage, and 1 with a history of alcoholism sustained massive hepatorenal damage and needed haemodialysis. Of the 6 patients (1 lost to follow-up) who were not given acetylcysteine 3 had hepatorenal failure and needed dialysis, and 1 died. The possibility of carbon tetrachloride poisoning after ingestion of, or exposure to, chlorinated hydrocarbons and in patients presenting with hepatic or renal impairment without obvious cause should not be ignored. Prompt treatment with acetylcysteine may minimise subsequent hepatorenal damage.