title: Influence of COMT inhibition on levodopa pharmacology and therapy.
abstract: Catechol O-methyltransferase (COMT) is an important enzyme that is linked directly to therapy with levodopa. Considering the demonstrated mechanism of action and pharmacologic profiles of COMT inhibitors, it is reasonable to hypothesize that these agents would improve the disability associated with Parkinson's disease. Two basic classes of COMT inhibitors are being studied in patients with PD: those that act exclusively extracerebrally or peripherally (e.g., entacapone) and those that cross the blood-brain barrier (e.g., tolcapone). With COMT inhibition, greater peripheral bioavailability of levodopa occurs in humans without an enhancement of peak plasma levels. It is reasonable to suggest that COMT inhibition will be associated with prolonged effects of levodopa in PD, without increased peak dose toxicity in the form of dyskinesias and hallucinations.
authors.affiliation: Rush University/Rush-Presbyterian St. Luke's Medical Center, Chicago, IL 60612, USA.
authors.forename: C G
authors.initials: CG
authors.lastname: Goetz
mesh_terms: D000818:Animals; D000978:Antiparkinson Agents / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000627:therapeutic use; D001577:Benzophenones / Q000494:pharmacology* / Q000627:therapeutic use; D065098:Catechol O-Methyltransferase Inhibitors; D015259:Dopamine Agents / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000627:therapeutic use; D004791:Enzyme Inhibitors / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000627:therapeutic use; D006207:Half-Life; D006801:Humans; D007980:Levodopa / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000627:therapeutic use; D009596:Nitrophenols; D010300:Parkinson Disease / Q000188:drug therapy* / Q000201:enzymology*; D000077867:Tolcapone
chemical_list: D000978:Antiparkinson Agents; D001577:Benzophenones; D065098:Catechol O-Methyltransferase Inhibitors; D015259:Dopamine Agents; D004791:Enzyme Inhibitors; D009596:Nitrophenols; D007980:Levodopa; D000077867:Tolcapone