Objective: To evaluate the efficacy and tolerability of risperidone in comparison with clonidine in the treatment of children and adolescents with Tourette's syndrome (TS).
Method: Following a 7- to 14-day single-blind, placebo lead-in, 21 subjects aged 7 to 17 years were randomly assigned to 8 weeks of double-blind treatment with clonidine or risperidone. Research scales evaluated tics and comorbid obsessive-compulsive and attention-deficit/hyperactivity symptoms.
Results: Risperidone and clonidine appeared equally effective in the treatment of tics in an intent-to-treat analysis, as rated by the Yale Global Tic Severity Scale (YGTSS). Risperidone produced a mean reduction in the YGTSS of 21%; clonidine produced a 26% reduction. Among subjects with comorbid obsessive-compulsive symptoms, 63% of the risperidone group and 33% of the clonidine group responded to treatment (not significant). The most common adverse event seen with both treatments was sedation, which was mild to moderate in severity. Sedation subsequently resolved with continued administration of the medication or with a dose reduction. No clinically significant extrapyramidal symptoms were observed.
Conclusions: In this pilot study, risperidone demonstrated efficacy equivalent to clonidine in the treatment of tic symptoms in children and adolescents with TS. Further research is needed to clarify the role of atypical antipsychotics in TS and to delineate potential benefits for comorbid obsessive-compulsive and attention-deficit/hyperactivity symptoms.