Based on their results, Brawman-Mintzer et al. 2005 suggest that adjunctive risperidone at low doses may represent a useful tool in the management of symptomatic GAD patients. They found statistically significant improvements in core anxiety symptoms, as demonstrated by greater reduction in HAM-A total scores (p=.034) and HAM-A psychic anxiety factor scores (p=.047) compared to placebo.
Brawman-Mintzer et al. 2005 also conclude that between-group differences in reported adverse events were not clinically significant. However, scrutinizing published data, a statistically significant difference can be detected: more risperidone-treated patients reported somnolence (9 out of 19 patients) over placebo group (3 of 20 patients); Fisher's exact, two tailed p=.047.
This statistical difference can be arguably of clinical relevance, since risperidone-induced calming effects may be in fact attributed to sedation rather than to specific anxiolytic effects. Somnolence in low doses risperidone group can be partially explained by drug-drug interactions