Clinical Pharmacology of Dopamine Agonists in Parkinson’s Disease

Oral levodopa is the most effective symptomatic treatment for Parkinson’s disease. Dopamine agonists are useful adjuvants to levodopa in the pharmacotherapy of parkinsonian patients. Monotherapy with dopamine agonists in early Parkinson’s disease has been advocated in order to delay the occurrence of complications associated with long term administration of levodopa. The use of dopamine agonists alone provides an adequate antiparkinsonian effect in only a minority of patients. In early stages of Parkinson’s disease, dopamine agonists can produce a clinical response comparable with levodopa but, thereafter, their efficacy wanes. Early initiation of combination therapy with levodopa and dopamine agonists appears to reduce the severity and delay the appearance of the complications associated with long term administration of levodopa.