Dopamine agonists in the treatment of Parkinson's disease.

Bromocriptine or pergolide can be used as initial monotherapy in Parkinson's disease. When used as an adjuvant to levodopa therapy, these drugs can result in clinical improvement and a decreased levodopa requirement. To avoid side effects, the starting dosage should be low (1.25 mg per day of bromocriptine or 0.05 mg of pergolide) and should be increased slowly. The standard daily dose of bromocriptine ranges from 7.5 to 60 mg, and of pergolide, from 0.75 to 4 mg. Combination therapy with low dosages of levodopa and a dopamine agonist may also decrease the incidence of side effects of both agents.