Available treatments for Tourette Syndrome (TS) are far from perfect. None eliminates all tics, and many treatments have substantial side effects. Recently, doctors have found that tics can be reduced by low doses of medications that mimic the action of dopamine. Dopamine is a neurotransmitter (brain messenger) which is associated with control of movement. The benefit from dopamine look-alikes may seem surprising since for years, dopamine blockers have been known to reduce tics. Levodopa is a naturally occurring amino acid which has been used for decades to treat other movement disorders. When given as a medicine, it is absorbed by the brain and turned into dopamine. We recently gave a single dose of levodopa to each of six volunteers with TS. We found that they had temporary improvement in their tics. However, until we compare levodopa to a placebo (sugar pill), we do not know for sure that the levodopa actually brought about the improvement. Also, we do not know how long such improvement, if any, may last. This study is designed to test whether levodopa, given for two months, can actually reduce tics in children and adults. If so, levodopa may provide a new choice for treatment. Moreover, such a result may require rethinking of prevailing views about the nature of the abnormality in the dopamine system that causes TS symptoms. Kevin J. Black, M.D. Washington University School of Medicine, St. Louis, MO Award: $27,735 Tourette Association of America Inc. – Research Grant Award 2000-2001