Pharmacological treatment for Tourette syndrome in children and adults: What is the quality of the evidence? A systematic review.

There are relatively few placebo-controlled trials of commonly prescribed medications. Studies are often of poor quality and short duration. There is evidence for the efficacy of each medication, but no drug is clearly superior. Clonidine and guanfacine are better tolerated than antipsychotics, but less effective. There is too little evidence to determine whether adults respond differently from children.