Open fluoxetine treatment of mixed anxiety disorders in children and adolescents.

An open-label pilot study examined fluoxetine treatment in 16 outpatients (9-18 years old) with mixed anxiety disorders. Following nonresponse to psychotherapy, fluoxetine monotherapy was started at 5 mg daily and was increased weekly by 5 or 10 mg daily for 6-9 weeks until improvement occurred or to a maximum of 40 mg (children under 12) or 80 mg (adolescents). Among patients on fluoxetine, severity of illness ratings were "much improved" (mean final Clinical Global Impression scale score 2.8 +/- 0.7). Clinical improvement occurred in 10 of 10 patients with current separation anxiety disorder, 8 of 10 with social phobia, 4 of 6 with specific phobia, 3 of 5 with panic disorder, and 1 of 7 with generalized anxiety disorder. Mean time to improvement was 5 weeks. Mean doses were 24 mg (0.7 mg/kg) for children and 40 mg (0.71 mg/kg) for adolescents. Side effects were transient and included drowsiness (31% of patients), sleep problems (19%), decreased appetite (13%), nausea (13%), abdominal pain (13%), and excitement (13%). No patient developed disinhibition, akathisia, or suicidality. These preliminary findings suggest fluoxetine effectiveness in separation anxiety disorder and social phobia. Youths with only one anxiety disorder appeared to respond to lower doses of fluoxetine than patients with multiple anxiety disorders (0.49 +/- 0.14 versus 0.80 +/- 0.28 mg/kg, p < 0.05).