Bromocriptine: low-dose therapy in Parkinson disease.

In a double-blind trial with a placebo phase, low-dose bromocriptine therapy (average dose, 15 mg per day) produced a significant improvement in 25 idiopathic parkinsonian patients. Tremor and bradykinesia were equally and significantly improved in both the levodopa-treated and the de novo patients. Rigidity was most improved in the levodopa-treated subjects. Age was not a factor in determining the dose of bromocriptine or the degree of improvement. Adverse effects occurred in 30% but were mild and dose-dependent. Four subjects, unable to tolerate initial doses of bromocriptine, withdrew from the trial. A low initial dose (1 mg per day) and slow escalation in dosage produced an optimal, though delayed improvement. Low-dose bromocriptine therapy is effective, does not induce significant dyskinesia nor on-off phenomenon, and is probably an alternative to levodopa as a drug of first choice in Parkinson disease.