A placebo controlled trial of risperidone in Tourette syndrome (2003)

Risperidone is dopamine antagonist, which means it reduces the binding of dopamine to dopamine receptors. As with other dopamine antagonists, risperidone initiated social anxiety in some users.  

Neurology. 2003 Apr 8;60(7):1130-5.

Scahill L, Leckman JF, Schultz RT, Katsovich L, Peterson BS.


Child Study Center, School of Nursing, Yale University, New Haven, CT 06520, USA. [email protected]



To evaluate the efficacy and safety of risperidone in children and adults with Tourette syndrome.


This was an 8-week, randomized, double-blind, placebo-controlled trial. The primary outcome measure was the Total Tic score of the Yale Global Tic Severity Scale (YGTSS).


Thirty-four medication-free subjects (26 children and 8 adults) ranging in age from 6 to 62 years (mean = 19.7 +/- 17.0 years) participated. YGTSS Total Tic scores were similar at baseline (26.0 +/- 5.1 for risperidone vs 27.4 +/- 8.5 for placebo). After 8 weeks of treatment (mean daily dose of 2.5 +/- 0.85), the 16 subjects on risperidone showed a 32% reduction in tic severity from baseline, compared to a 7% reduction for placebo patients (n = 18) (F[2,64] = 6.07; p = 0.004). The 12 children randomized to risperidone showed a 36% reduction in tic symptoms compared to an 11% decrease in the 14 children on placebo (F[2,48] = 6.38; p = 0.004). Two children on risperidone showed acute social phobia, which resolved with dose reduction in one subject but resulted in medication discontinuation in the other. A mean increase in body weight of 2.8 kg was observed in the risperidone group compared to no change in placebo (F[2,64] = 10.68; p = 0.0001). No extrapyramidal symptoms and no clinically significant alterations in cardiac conduction times or laboratory measures were observed.


Risperidone appears to be safe and effective for short-term treatment of tics in children or adults with Tourette syndrome. Longer-term studies are needed to evaluate the durability of efficacy and safety over time.