Effects of DA agonist in Huntington disease hyperkinesia

Apomorphine, bromocryptine, lysuride, diazepam and cyproheptadine were administered to 11 patients with Huntington's disease (HD). The evaluation of the pharmacologic activity of different drugs on abnormal involuntary movements (AIM) was determined by means of an arbitrary clinical method. Apomorphine, diazepam and cyproheptadine succeeded in improving the AIM, while bromocryptine and lysuride did not modify the clinical pattern or provoked (bromocryptine) a worsening in some patients. The growth hormone (GH) responses to apomorphine and bromocryptine were determined in 6 patients. The relationship between clinical, endocrine results and pharmacologic action of apomorphine is discussed, suggesting that the reducing effect of apomorphine on AIM of HD may be due to its sedative action.