Land: Verenigde Staten
Taal: Engels
Bron: NLM (National Library of Medicine)
METHYLDOPA (UNII: 56LH93261Y) (METHYLDOPA ANHYDROUS - UNII:M4R0H12F6M)
Cardinal Health
METHYLDOPA
METHYLDOPA ANHYDROUS 250 mg
PRESCRIPTION DRUG
Abbreviated New Drug Application
METHYLDOPA- METHYLDOPA TABLET CARDINAL HEALTH ---------- DESCRIPTION Methyldopa is an antihypertensive and is the L-isomer of alpha-methyldopa. It is levo-3-(3,4- dihydroxyphenyl)-2-methylalanine sesquihydrate. Methyldopa is supplied as tablets for oral administration, containing 250 mg and 500 mg of methyldopa. The amount of methyldopa is calculated on the anhydrous basis. Its molecular formula is C H NO •1 1/2 H O, with a molecular weight of 238.24, and its structural formula is: Methyldopa is a white to yellowish white, odorless fine powder and is sparingly soluble in water. The tablets contain the following inactive ingredients: colloidal silicon dioxide, croscarmellose sodium, hypromellose, magnesium stearate, microcrystalline cellulose, polydextrose, polyethylene glycol, sodium lauryl sulfate, titanium dioxide, triacetin, FD&C yellow #6 aluminum lake and FD&C blue #2 aluminum lake. CLINICAL PHARMACOLOGY Methyldopa is an aromatic-aminoacid decarboxylase inhibitor in animals and in man. Although the mechanism of action has yet to be conclusively demonstrated, the antihypertensive effect of methyldopa probably is due to its metabolism to alpha-methylnorepinephrine, which then lowers arterial pressure by stimulation of central inhibitory alpha-adrenergic receptors, false neurotransmission, and/or reduction of plasma renin activity. Methyldopa has been shown to cause a net reduction in the tissue concentration of serotonin, dopamine, norepinephrine, and epinephrine. Only methyldopa, the L-isomer of alpha-methyldopa, has the ability to inhibit dopa decarboxylase and to deplete animal tissues of norepinephrine. In man, the antihypertensive activity appears to be due solely to the L-isomer. About twice the dose of the racemate (DL-alpha-methyldopa) is required for equal antihypertensive effect. Methyldopa has no direct effect on cardiac function and usually does not reduce glomerular filtration rate, renal blood flow, or filtration fraction. Cardiac output usually is maintained without cardiac acceleration. In so Lees het volledige document