There are 4 classes of drugs used to treat PD symptoms. They work on a
different part of the neurotransmission system. They are; 1.) Replacement
therapy. Sinemet a dopamine precursor (it is cnverted into dopamine).
2.) Dopamine agonists. (Mirapex, Requip) They directly stimulate the dopamine receptors. 3.) Inhibitirs of dopamine metabolism. Comptan
(Entacapone) inhibits the enymye COMP, and Azilect inhibits the enzyme
COMT. 4.) Anticholinergic agents. ( Cogentin, Artane).