Anxiety and Xanax: Clinical studies

Anxiety Disorders: Xanax tablets were compared to placebo in double blind clinical studies (doses up to 4 mg/day) in patients with a diagnosis of anxiety or anxiety with associated depressive symptomatology.

Xanax was significantly better than placebo at each of the evaluation periods of these four week studies as judged by the following psychometric instruments: Physician's Global Impressions, Hamilton Anxiety Rating Scale, Target Symptoms, Patient's Global Impressions, and Self-Rating Symptom Scale.

Panic Disorder: Support for the effectiveness of Xanax in the treatment of panic disorder came from three short-term, placebo-controlled studies (up to 10 weeks) in patients with diagnoses closely corresponding to DSM-III-R criteria for panic disorder.

The average dose of Xanax was 5-6 mg/day in two of the studies, and the doses of Xanax were fixed at 2 and 6 mg/day in the third study.

In all three studies, Xanax was superior to placebo on a variable defined as "the number of patients with zero panic attacks" (range, 37-83% met this criterion), as well as on a global improvement score. In two of the three studies, Xanax was superior to placebo on a variable defined as "change from baseline on the number of panic attacks per week" (range, 3.3-5.2), and also on a phobia rating scale.

A subgroup of patients who were improved on Xanax during short-term treatment in one of these trials was continued on an open basis up to 8 months, without apparent loss of benefit.