Ülke: ABD
Dil: İngilizce
Kaynak: NLM (National Library of Medicine)
METHYLDOPA (UNII: 56LH93261Y) (METHYLDOPA ANHYDROUS - UNII:M4R0H12F6M)
Teva Pharmaceuticals USA Inc
METHYLDOPA
METHYLDOPA ANHYDROUS 250 mg
PRESCRIPTION DRUG
Abbreviated New Drug Application
METHYLDOPA- METHYLDOPA TABLET, FILM COATED TEVA PHARMACEUTICALS USA INC ---------- METHYLDOPA TABLETS USP 2931 2932 DESCRIPTION Methyldopa USP is an antihypertensive drug. Methyldopa USP is the L-isomer of alpha-methyldopa. Its chemical name is levo-3-(3,4- dihydroxyphenyl)- 2-methylalanine sesquihydrate. Its structural formula is: C H NO • 1 / H O M.W. 238.24 Methyldopa USP is a white to yellowish white, odorless fine powder and is sparingly soluble in water. Each tablet, for oral administration, contains 250 mg or 500 mg of methyldopa USP. Potency is calculated in the anhydrous basis. Inactive ingredients: calcium sulfate (anhydrous), citric acid (anhydrous), colloidal silicon dioxide, edetate disodium (dihydrate), ethyl cellulose, hydroxypropyl cellulose, hypromellose, magnesium stearate, methylcellulose, polyethylene glycol, sodium starch glycolate, talc, and titanium dioxide. CLINICAL PHARMACOLOGY Methyldopa is an aromatic-amino-acid 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 some pat Belgenin tamamını okuyun