A double-blind trial of bromocriptine in Parkinson's disease

Twenty-two patients entered a double-blind trial to test the efficacy of bromocriptine therapy in patients with Parkinson's disease who were already stabilized on conventional L-Dopa therapy. Of these, three patients who were receiving placebo withdrew when no improvement occurred and control became complicated. Another four patients taking active drug withdrew because of side effects, but only in one case was the symptom (nausea and vomiting) thought to be a true effect of the drug. Of the 15 patients who completed the trial, nine were taking active drug and six took placebo. Although more than half the patients in each group were subjectively improved, measurement scales of functional disability and physical examination revealed no significant change in either group. Side effects encountered included nausea, dyskinesia, and hallucinations. It was concluded that bromocriptine does not offer any additional benefit to patients with Parkinson's disease who are stabilized on L-Dopa therapy, but may have a place in those patients who encounter side effects due to fluctuations in serum and tissue levels of L-Dopa.