entacapone
Also found in: Dictionary, Wikipedia.
entacapone
[en-tak´ah-pōn]entacapone
Pharmacologic class: Catechol O-methyltransferase (COMT) inhibitor
Therapeutic class: Antidyskinetic
Pregnancy risk category C
Action
Inhibits COMT, the primary enzyme involved in metabolizing levodopa. This inhibition increases levodopa blood level and duration of action, easing symptoms of Parkinson's disease.
Availability
Tablets: 200 mg
Indications and dosages
➣ Adjunctive treatment of idiopathic Parkinson's disease in patients experiencing wearing off of carbidopa-levodopa effects
Adults: 200 mg P.O. with each carbidopa-levodopa dose, to a maximum of eight times daily (1,600 mg)
Contraindications
• Hypersensitivity to drug
Precautions
Use cautiously in:
• hepatic or renal dysfunction, hypertension, heart disease
• pregnant and breastfeeding patients.
Administration
• Give without regard to food.
• Administer at same time as carbidopa-levodopa. Make sure patient swallows tablet whole.
☞ Don't withdraw drug abruptly.

Adverse reactions
CNS: dizziness, depression, drowsiness, disorientation, memory loss, agitation, delusions, hallucinations, paranoia, euphoria, dyskinesia, hyperkinesia, light-headedness, paresthesia, heaviness of limbs, numbness of fingers
CV: tachycardia, orthostatic hypotension, hypertension
GI: nausea, vomiting, epigastric pain, flatulence
GU: urine discoloration
Respiratory: upper respiratory tract infection, dyspnea, sinus congestion
Other: fever
Interactions
Drug-drug. Ampicillin, chloramphenicol, cholestyramine, erythromycin, probenecid, rifampin: decreased entacapone excretion
Bitolterol, dobutamine, dopamine, epinephrine, isoetherine, isoproterenol, methyldopa, norepinephrine: increased heart rate, increased risk of arrhythmias, excessive blood pressure changes
MAO inhibitors: increased risk of toxicity
Drug-behaviors. Alcohol use: increased risk of adverse reactions
Patient monitoring
• Monitor vital signs, watching especially for orthostatic hypotension.
• Evaluate neurologic status closely. Check for hallucinations and new onset or exacerbation of dyskinesia.
• Assess respiratory status, particularly for dyspnea and signs and symptoms of upper respiratory tract infection.
• Monitor nutritional and hydration status if patient experiences vomiting.
Patient teaching
• Instruct patient to swallow tablet whole and to take it at same time as carbidopa-levodopa.
☞ Caution patient not to stop taking drug abruptly.
• Advise patient to move slowly when sitting up or standing, to avoid dizziness or light-headedness from sudden blood pressure decrease.
• Caution patient to avoid driving and other hazardous activities until drug no longer affects concentration and alertness.
☞ Instruct patient (and caregiver) to institute safety measures at home to prevent injury related to disease or drug's adverse CNS effects.
• As appropriate, review all other significant adverse reactions and interactions, especially those related to the drugs and behaviors mentioned above.
entacapone
A nitrocatechol-class COMT (catechol-O-methyltransferase) inhibitor used to improve motor performance in Parkinson patients receiving l-DOPA/carbidopa.Adverse effects
Dyskinesia, which often resolves with ongoing therapy; diarrhoea, nausea and abdominal pain; asymptomatic red-brown urine.