[Initial treatment of Parkinson's disease]

The initial treatment of Parkinson's disease should be addressed to improve symptoms, slow down the progression of the illness and avoid long and short term complications. Drugs currently available for symptomatic treatment are levodopa, dopaminergic agonists, anticholinergics and amantadine. Levodopa is still the goldstandard. Both the standard preparations of carbidopa/levodopa or benserazide/levodopa and the slow release preparations are suitable for initial treatment. However, when to start levodopa remains controversial. Dopaminergic agonists are useful symptomatic drugs. They can be used in monotherapy, but usually require the addition of levodopa to obtain a satisfactory long term therapeutic response. Used as adjuvant treatment to levodopa, they help lowering the dosage of levodopa. Anticholinergic drugs effectively improve symptoms such as tremor and rigidity but their use is limited by their side effects, particularly in older people. Amantadine may be a useful drug for initial treatment of Parkinson's disease when symptoms are not severe. Symptomatic treatment should be considered individually in each patient. If there is only slight disability, treatment may be started with amantadine alone or with a dopaminergic agonist. If there is greater disability, levodopa or the simultaneous use of levodopa and a dopaminergic agonist should be considered. Anticholinergic drugs should be reserved for young patients with tremor as the main symptom. The newer dopamine agonists and inhibitors of catachol-o-methyltransferase (COMT) are coming therapeutic options. Selegiline, a MAOB inhibitor with a possible neuroprotective effect, should also be considered as initial option for Parkinson's disease.