&NA;A double‐blind comparison of clonazepam and lorazepam was conducted in 24 patients with acute mania. Patients received either clonazepam or lorazepam alone for 14 days. Treatment with lorazepam produced marked improvement in symptomatology, while treatment with clonazepam failed to demonstrate a significant therapeutic effect. Sixty‐one percent of patients responded to treatment with lorazepam, with 38.5% achieving remission. This compares to an 18.2% response rate and 0% remission rate in patients treated with clonazepam. These findings support the usefulness of lorazepam in the treatment of acute mania.(J Clin Psychopharmacol 1990;10:403‐408)