Patient considerations in early management of Parkinson's disease: focus on extended-release pramipexole.

This article reviews the role of an extended-release formulation of pramipexole in the treatment of Parkinson's disease at an early stage. Pramipexole is a nonergot D(2)/D(3) synthetic aminobenzothiazole derivative that is effective as monotherapy in early disease and as an adjunct to levodopa in patients with motor fluctuations. Although levodopa is the current "gold standard" for treatment of Parkinson's disease, its effectiveness fades rapidly and its use results in serious motor fluctuations (on-off, wearing-off, freezing, involuntary movements) for most patients with the disease. Pramipexole has selective actions at dopamine receptors belonging to the D(2) subfamily, where it possesses full activity similar to dopamine itself. Its preferential affinity for the D(3) receptor subtype could contribute to its efficacy in the treatment of both the motor and psychiatric symptoms of Parkinson's disease. The best approach to medical management of early Parkinson's disease remains controversial. While enormous progress has been made in the treatment of the disease, challenges still remain. A variety of treatment-related and patient-related factors must be taken into account when making these decisions. The current approach to treatment of early Parkinson's disease depends in part on individual patient factors, including age, severity and nature of symptoms and their impact, presence of cognitive dysfunction, possible underlying behavioral factors predisposing to impulse control disorders, and other comorbidities. Today, the once-daily extended-release formulation of pramipexole offers the advantages of easy continuous delivery of drug and convenience to patients, particularly early in the disease when monotherapy is the rule. Thus, a new "levodopa-sparing" paradigm for treating Parkinson's disease may now be possible, whereby patients are initially treated with pramipexole and levodopa is added only as necessary.