Recent articles in the press have trumpeted a new era in the management of Parkinson's disease: dopamine agonists have now replaced levodopa for initial treatment.

The dopamine agonist pramipexole (Mirapex - Boehringer Ingelheim) is the second drug approved by the FDA for treatment of moderate to severe restless legs syndrome (RLS). Ropinirole (Requip), another dopamine agonist, was approved for RLS in 2005. Both of these drugs were first approved for treatment of Parkinson's disease.

Pramipexole (Mirapex - Pharmacia & Upjohn) and ropinirole (Requip - SmithKline Beecham), two new dopamine agonists, have been approved by the US Food and Drug Administration (FDA) for treatment of both early (without levodopa) and advanced (with levodopa) Parkinson's disease. Bromocriptine (Parlodel) and pergolide (Permax) are older dopamine agonists marketed in the USA for adjunctive use with levodopa.

Ropinirole (Requip - GlaxoSmithKline), a dopamine agonist already available for treatment of Parkinson's disease, is now the first drug approved by the FDA for treatment of moderate to severe restless legs syndrome (RLS).

Rotigotine (Neupro - Schwarz Pharma), a nonergot dopamine agonist in a transdermal patch formulation, was recently approved by the FDA for treatment of early Parkinson's disease (PD).

The motor symptoms of Parkinson's disease (PD) are caused primarily by degeneration of dopaminergic neurons in the substantia nigra. The nonmotor symptoms of the disease are thought to be caused by degeneration of other neurotransmitter systems. No disease-modifying drugs are available for treatment of PD.

Apomorphine (Apokyn - Mylan/Bertek), an injected non-ergot dopamine agonist, was recently approved by the FDA for intermittent subcutaneous (SC) treatment of hypomobility ("off" episodes) in patients with advanced Parkinson's disease. It has been available in Europe for many years.

Levodopa combined with carbidopa (Sinemet) is the treatment of choice for Parkinson's disease (Medical Letter, 30:113, 1988). After prolonged treatment, however, the symptoms of the disease often become difficult to manage. The benefit from each dose becomes shorter (the 'wearing-off' effect), sudden fluctuations occur between mobility and immobility (the 'on-off' phenomenon), and abnormal involuntary movements (dyskinesias) may become frequent. The dopamine agonist bromocriptine (Parlodel) can ameliorate some of these effects. Two new drugs, pergolide (Permax - Lilly), another dopamine...

Cabergoline (Dostinex - Pharmacia & Upjohn), an ergot alkaloid derivative recently marketed for treatment of hyperprolactinemia, is a selective D2 dopamine agonist that inhibits prolactin-secreting cells in the pituitary. Bromocriptine (Parlodel - Sandoz), the drug most commonly used for this condition, is also a D2 agonist, but affects D1 receptors as well.

The FDA has approved a new tablet formulation of bromocriptine mesylate (Cycloset – VeroScience) for treatment of type 2 diabetes in adults. Bromocriptine (Parlodel, and others) is an ergot-derived dopamine agonist that has been used for more than 20 years to treat hyperprolactinemia, acromegaly, Parkinson’s disease and restless leg syndrome.