The drug treatment of Parkinson's disease.

The drug treatment of Parkinson's disease should be tailored to the age of the patient, coexistence of dementia or postural hypotension, duration of the disease process and the emergence of side effects. In the early stages of the disease when disability is minimal, amantadine or anti-cholinergic drugs may suffice. As the patient's lifestyle becomes hampered, levodopa in combination with carbidopa or benserazide is introduced. Mild dopa induced dyskinesia can be ignored but when it is troublesome the dose of levodopa should be reduced. Fluctuations are minimised by giving small doses of levodopa frequently throughout the day or by adding bromocriptine to the drug regimen. Postural symptoms often respond to fludrocortisone and elevation of the head of the bed. In elderly or demented patients anticholinergic drugs and amantadine should be avoided. In these patients small doses of levodopa alone may be preferable to the combined preparations. More effective drugs with fewer side effects are likely to emerge with future successful research into the different types of dopamine receptors and other possible transmitters.