Comtan

• Antiparkinson Agents
• Antidyskinetics
• Central Nervous System Agents
• ATC:N04BX02

• Comtan
• Entacapona [Inn-Spanish]
• Entacapone [Usan:Inn]
• Entacaponum [Inn-Latin]

• No information avaliable

C₁₄H₁₅N₃O₅

http://www.rxlist.com/cgi/generic3/entac.htm

Comtan FDA

No information avaliable

305.286 g/mol

No information avaliable

No information avaliable

Solid

0.53

Tablet

For as an adjunct to levodopa / carbidopa to treat patients with idiopathic Parkinson's Disease who experience the signs and symptoms of end-of-dose "wearing-off".

Entacapone is used in the treatment of Parkinson’s disease as an adjunct to levodopa/carbidopa therapy. Entacapone is a selective and reversible inhibitor of catechol-O-methyltransferase (COMT). In mammals, COMT is distributed throughout various organs with the highest activities in the liver and kidney. COMT also occurs in the heart, lung, smooth and skeletal muscles, intestinal tract, reproductive organs, various glands, adipose tissue, skin, blood cells and neuronal tissues, especially in glial cells. COMT catalyzes the transfer of the methyl group of S-adenosyl-L-methionine to the phenolic group of substrates that contain a catechol structure. Physiological substrates of COMT include dopa, catecholamines (dopamine, norepinephrine, and epinephrine) and their hydroxylated metabolites. The function of COMT is the elimination of biologically active catechols and some other hydroxylated metabolites. In the presence of a decarboxylase inhibitor, COMT becomes the major metabolizing enzyme for levodopa, catalyzing the metabolism to 3-methoxy-4-hydroxy-L-phenylalanine (3-OMD) in the brain and periphery.

Entacapone is rapidly absorbed (approximately 1 hour). The absolute bioavailability following oral administration is 35%.

Side effect include increase the occurrence of orthostatic hypotension, severe rhabdomyolysis, dyskinesia, hallucinations, hyperkinesia, hypokinesia, dizziness, fatigu,e gastrointestinal effects including abdominal pain constipation diarrhea nausea

Patients should be instructed to take C.M.A. only as prescribed.

Patients should be informed that hallucinations can occur.

Patients should be advised that they may develop postural (orthostatic) hypotension with or without symptoms such as dizziness, nausea, syncope, and sweating. Hypotension may occur more frequently during initial therapy. Accordingly, patients should be cautioned against rising rapidly after sitting or lying down, especially if they have been doing so for prolonged periods, and especially at the initiation of treatment with COMTAN.

Patients should be advised that they should neither drive a car nor operate other complex machinery until they have gained sufficient experience on C.M.A. to gauge whether or not it affects their mental and/or motor performance adversely. Because of the possible additive sedative effects, caution should be used when patients are taking other CNS depressants in combination with COMTAN.

Patients should be informed that nausea may occur, especially at the initiation of treatment with COMTAN.

Patients should be advised of the possibility of an increase in dyskinesia.

Patients should be advised that treatment with entacapone may cause a change in the color of their urine (a brownish orange discoloration) that is not clinically relevant. In controlled trials, 10% of patients treated with C.M.A. reported urine discoloration compared to 0% of placebo patients.

Although C.M.A. has not been shown to be teratogenic in animals, it is always given in conjunction with levodopa/carbidopa, which is known to cause visceral and skeletal malformations in the rabbit. Accordingly, patients should be advised to notify their physicians if they become pregnant or intend to become pregnant during therapy.

Entacapone is excreted into maternal milk in rats. Because of the possibility that entacapone may be excreted into human maternal milk, patients should be advised to notify their physicians if they intend to breastfeed or are breastfeeding an infant.

Humans and other mammals