Lorazepam was compared with diazepam for the treatment of acute convulsions and status epilepticus in 102 children in a prospective, open, 'odd and even dates' trial. Convulsions were controlled in 76 per cent of patients treated with a single dose of lorazepam and 51 per cent of patients treated with a single dose of diazepam. Significantly fewer patients treated with lorazepam required additional anticonvulsants to terminate the seizure. Respiratory depression occurred in 3 per cent of lorazepam-treated patients and 15 per cent of diazepam-treated patients. No patient who received lorazepam required admission to the intensive care unit for either respiratory depression or persisting status epilepticus. Rectally administered lorazepam appeared to be particularly valuable (100 per cent efficacy) when venous access was not possible.