A case of alprazolam, but not lorazepam, inducing manic symptoms.

A patient developed manic symptoms during treatment with alprazolam. These symptoms remitted upon discontinuation of treatment, but reemerged during a second trial with alprazolam. Subsequent administration of an equivalent dosage of lorazepam did not induce manic symptoms. The clinical and theoretical implications of these findings are discussed in relation to the possible mechanisms of action of alprazolam, a novel benzodiazepine.