Summary: Buspirone, an anxiolytic unrelated to benzodiazepines that may act at the presynaptic dopamine receptor, was given to 11 patients with Parkinson's disease in an open label study. Seven patients completed the initial 10 week study achieving doses of 50–70 mg/day without any significant change in their clinical status. Six patients continued for an additional 3–11 weeks with increases in dose to 65–100 mg/day. Two of the three most severely affected patients had mild worsening of parkinsonian symptoms. Buspirone is ineffective in the treatment of Parkinson's disease, but at anxiolytic doses (<40 mg/day) does not adversely affect parkinsonian disability.