Paroxetine treatment of generalized anxiety disorder: a double-blind, placebo-controlled study.

OBJECTIVE This study assessed the efficacy of two fixed doses of paroxetine in the treatment of generalized anxiety disorder. METHOD Outpatients (N=566) with generalized anxiety disorder and no other axis I disorder were eligible if they scored >/=20 on the Hamilton Rating Scale for Anxiety (with a score of 2 or higher on the anxious mood and tension items). Following a 1-week placebo run-in phase, patients were randomly assigned to 8 weeks of treatment with paroxetine, 20 or 40 mg/day, or placebo. The primary outcome measure was the change from baseline in total score on the Hamilton anxiety scale. Response was defined as a rating of "very much improved" or "much improved" on the Clinical Global Impression global improvement measure; remission was defined as a Hamilton anxiety scale score </=7. Change in functional impairment was measured with the Sheehan Disability Scale. RESULTS At 8 weeks, reductions in total score on the Hamilton anxiety scale were significantly greater for both paroxetine groups. Response was achieved by 62% and 68% of the patients receiving 20 and 40 mg of paroxetine, respectively, compared with a 46% response rate in the placebo group. Remission was achieved by 30% and 36% of patients in the 20- and 40-mg paroxetine groups, respectively, compared with 20% given placebo. For all three domains of the Sheehan Disability Scale, significantly greater improvement was seen with paroxetine than placebo. Both doses of paroxetine were well tolerated. CONCLUSIONS This study demonstrates that paroxetine is an efficacious and well-tolerated treatment for generalized anxiety disorder.