Purpose: Excessive sweating (hyperhidrosis) is an overlooked and potentially disabling symptom, which is often seen in social anxiety disorder (SAD). We conducted a retrospective review of data acquired in patients with SAD who had participated in placebo-controlled clinical trials of fluoxetine, cognitive behavior therapy, clonazepam and gabapentin. Four specific topics were addressed: (1) overall levels of sweating; (2) characteristics of those with hyperhidrosis; (3) a comparison of active treatments relative to placebo on hyperhidrosis; and (4) an examination of baseline sweating severity as a predictor of treatment outcome.
Methods: Using the Brief Social Phobia Scale (BSPS) and Social Phobia Inventory (SPIN), we examined the above questions.
Results: Hyperhidrosis was found in 24.8-32.3% of 375 subjects assessed, depending upon the scale used. Hyperhidrosis was associated with higher levels of disability, fear, avoidance, and other physiologic symptoms. While treatment in general was associated with a reduction in the rate of hyperhidrosis from 23.7% to 9.7% (BSPS), and 34.0% to 15.5% (SPIN), only fluoxetine differed significantly from placebo in respect of change in sweating score from baseline to endpoint. In an ANCOVA, gabapentin differed from placebo on the SPIN.
Conclusion: We conclude that hyperhidrosis is frequently seen in patients with SAD, and that its response to treatment is variable. Further attention should be paid to the possible importance of this symptom in social anxiety.