Entacapone
Indications
Entacapone is used for:
Parkinson's disease
Adult Dose
Oral
Adjunct to levodopa treatment in Parkinson's disease
Adult: 200 mg w/ each levodopa/dopa decarboxylase inhibitor dose. Max: 200 mg 10 times daily (2,000 mg daily).
Hepatic Impairment
Safety and efficacy not established
Child Dose
Renal Dose
Renal Impairment
Dose adjustment not necessary
Administration
May be taken with or without food.
Contra Indications
History of neuroleptic malignant syndrome and nontraumatic rhabdomyolysis. Phaeochromocytoma. Hepatic impairment.
Precautions
Levodopa-induced orthostatic hypotension may be aggravated. Abrupt withdrawal. Concomitant use with a selective MAO-A and MAO-B inhibitor, or concomitant use with a selective MAO-A plus a selective MAO-B inhibitor. Biliary obstruction. Impairs ability to drive and operate machinery. Pregnancy and lactation. Children and elderly.
Lactation: excretion in milk unknown; use with caution
Pregnancy-Lactation
Pregnancy Category: C
Lactation: excretion in milk unknown; use with caution
Interactions
Drugs metabolised by COMT e.g. adrenaline, apomorphine, dobutamine, dopamine, isoprenaline, methyldopa, noradrenaline and remiterol. Iron preparations and levodopa. Avoid ethanol.
Side Effects
Side effects of Entacapone :
>10%
Dyskinesia (25%), Nausea (14%), Diarrhea (10%), Hyperkinesia (10%), Urine discoloration (10%)
1-10%
Hypokinesia (9%), Dizziness (8%), Abdominal pain (8%), Fatigue (6%), Constipation (6%), Back pain (4%), Vomiting (4%), Dry mouth (3%), Dyspnea (3%), Increased sweating (2%), Back pain (2%), Anxiety (2%), Somnolence (2%), Dyspepsia (2%), Flatulence (2%), Purpura (2%), Asthenia (2%), Hallucinations (1-4%), Taste perversion (1%), Agitation (1%), Gastritis (1%), Bacterial infection (1%)
Frequency Not Defined
Insomnia, Postural hypotension, Confusion, Dopaminergic side affects due to increased dopamine levels
Rare: rhabdomyolysis, retroperitoneal fibrosis
Mode of Action
Entacapone is a selective, reversible, peripheral inhibitor of COMT, an enzyme involved in the metabolism of dopamine and levodopa. It is used in patients with Parkinson's disease and "end-of-dose" motor fluctuations that cannot be stabilised on levodopa combinations alone.