We studied the efficacy of nimodipine in severely head-injured patients in a randomized study. Of 176 patients who received nimodipine, 2 mg/h iv for 2 day, 53% had a favorable outcome (moderate or good recovery). Of 175 control patients, 49% had a favorable outcome. This difference was not statistically significant but does not exclude the possibility that a study of a larger number of patients could show a clinically useful benefit.