ABSTRACT
Drug therapy is central to the management of patients with Parkinson's disease (PD). The primary aim of therapy is to relieve symptoms and improve function. The choice of initial drug therapy has to take into account a variety of clinical factors and the emphasis should be on informing the patient of the short- and long-term benefits and risks of particular drug classes. The rationale for levodopa in the treatment of PD centres around the notion that the symptoms of the disease result from a deficiency of the neurotransmitter dopamine in the striatum; this occurs as a result of progressive degeneration of the pigment-containing cells of the pars compacta of the substantia nigra. Amantadine is an unusual drug. Its anti-parkinsonian effect was discovered by chance when it was being used as an anti-viral agent. Pramipexole is an effective adjunct therapy to producing significant reductions in 'off' time and reduction in the dose of levodopa.
