Match the choice of PD drug class to disease stage and the individual side-effect profile, and use the tolcapone versus entacapone distinction to drive COMT inhibitor selection. When levodopa efficacy fluctuates after meals, instruct the patient to separate medication intake from protein-rich food by at least thirty to ninety minutes.

Amantadine is mainly useful when dyskinesia control matters more than simple symptom relief; We have the dopamine precursor, which is levodopa combined with carbidopa—commonly known as Sinemet or Sinemet C-R; Anticholinergics such as trihexyphenidyl and benztropine are reserved for tremor or dystonia that do not respond well to levodopa; Dopamine agonists remain useful as early therapy or as adjuncts for fluctuation control; COMT inhibitors are used to prolong levodopa benefit when wearing off becomes an issue