A total of 418 patients with aluminium phosphide poisoning admitted during January 1981 to December 1987, were studied and analysed for various clinical parameters. A steady increase in the number of patients was seen during the last 7 yr. Maximum number belonged to the younger generation and nature of poisoning was suicidal in most of these patients. Dose of poison consumed varied, but most patients consumed two tablets (6 g). A wide range of symptoms and signs was seen, the commonest being gastrointestinal manifestations and shock. Cardiac arrhythmias and conduction disturbances were seen in 38.2 per cent patients. The overall mortality was 77.2 per cent. Indices of a bad prognosis included poor response to dopamine infusion and continuous increase in its dosage, chest infections, adult respiratory distress syndrome and disseminated intravascular coagulation. The complications noticed were pericarditis, congestive cardiac failure, acute gastrointestinal haemorrhage and acute respiratory arrest. Histopathology of various organs showed changes suggestive of cellular hypoxia but the mechanism of ECG changes and of the complications could not be elucidated.