Rebound--the relative worsening of symptoms on discontinuation of treatment as compared to baseline symptoms--is distinguished from withdrawal. Case reports and a clinical study are presented to illustrate the management of patients with panic disorder who are taking short- and intermediate-acting benzodiazepines and are experiencing rebound anxiety. The authors present the results of switching over to clonazepam 48 patients with panic disorder who were experiencing rebound effects with alprazolam. Eighty-two percent (39) of the patients rated clonazepam as being "better" than alprazolam due to decreased dosing frequency and lack of interdose anxiety. The authors conclude that clonazepam can be a useful alternative to alprazolam and other short-acting benzodiazepines in the treatment of anxiety disorders. Clonazepam offers the advantage of antipanic efficacy without the relative side effect problems seen with tricyclic antidepressants and monoamine oxidase inhibitors.