Forty-eight patients currently experiencing panic attacks were randomly assigned to double-blind treatment with alprazolam, diazepam, or placebo. Efficacy was assessed using the Hamilton Rating Scale for Anxiety and a panic attack frequency rating scale. Results indicate that the two active treatments appeared equally effective in reducing both the frequency of panic attacks and the severity of generalized anxiety when compared with placebo. Overall, these data support the use of benzodiazepines in the treatment of panic disorder.