DOUBLE-BLIND, FIXED-DOSE, PLACEBO-CONTROLLED STUDY OF PAROXETINE IN THE TREATMENT OF PANIC DISORDER

Objective: This study teas designed to determine the minimum paroxetin e dose effective for treating panic disorder. Method: Of 425 patients with DSM-III-R panic disorder with or without agoraphobia who underwen t a 2-week drug-free screening period, 278 patients were randomly assi gned to double-blind treatment with a 10-week course of placebo or par oxetine at a dose of 10, 20, or 40 mg/day. Results: At 40 mg/day, paro xetine was superior to placebo across the majority of outcome measures . Despite a mean of 9.5 to 11.6 full panic attacks during the screenin g period, 86.0% of the patients taking 40 mg of paroxetine, 65.2% of t hose taking 20 mg, 67.4% of those taking 10 mg, and 50.0% of the place bo-treated patients were free of full panic attacks during the 2 weeks ending at week 10. The 40-mg paroxetine group experienced significant ly greater global improvement than the placebo group and significantly greater improvement in frequency of full and limited-symptom panic at tacks, intensity of full panic attacks, phobic fear, anxiety, and depr essive symptoms, usually evident by week 4. All doses of paroxetine we re well tolerated and adverse effects were consistent with those assoc iated with selective serotonin reuptake inhibitors. Conclusions: Parox etine is art effective and well-tolerated short-term treatment of pani c disorder. The minimum dose demonstrated to be significantly superior to placebo was 40 mg/day, although some patients did respond at lower doses.