Methyldopa is used alone or in combination with other classes of antihypertensive agents in the management of hypertension. Although other antihypertensive drug classes (angiotensin-converting enzyme [ACE] inhibitors, angiotensin II receptor antagonists, calcium-channel blockers, and thiazide diuretics) are preferred for the initial management of hypertension in adults, centrally acting agents such as methyldopa may be considered as add-on therapy if goal blood pressure cannot be achieved with the recommended drugs.
IV methyldopate hydrochloride may be used for the management of hypertension when parenteral hypotensive therapy is necessary.
Methyldopa generally is most effective when used with a diuretic. The use of a diuretic may prevent tolerance to methyldopa and permit reduction of methyldopa dosage. Diuretics may also prevent sodium retention and increased plasma volume that may occur after prolonged methyldopa therapy.
(See Cautions: Cardiovascular Effects.)Methyldopa also has been used with other antihypertensive agents, permitting a reduction in the dosage of each drug and, in some patients, minimizing adverse effects while maintaining blood pressure control. (See Drug Interactions: Diuretics and Hypotensive Agents.)The possibility that geriatric patients may not tolerate the adverse cognitive effects of centrally acting hypotensive agents such as methyldopa should be considered. Methyldopa is generally considered to be safe for use in patients with renal failure.
Hypertension during Pregnancy
Methyldopa has been used effectively for the management of hypertension in pregnant women without apparent substantial adverse effects on the fetus.
The goal of antihypertensive treatment in pregnant women with hypertension is to minimize the acute complications of maternal hypertension while avoiding therapy that would compromise fetal well-being. Antihypertensive therapy is recommended in pregnant women with chronic hypertension who have persistent, severely elevated levels of blood pressure (e.g., systolic blood pressure of 160 mm Hg or higher or diastolic blood pressure of 105 mm Hg or higher); it is less clear whether antihypertensive therapy should be initiated in women with mild to moderate chronic hypertension. Although methyldopa has been used for many years in the management of hypertension in pregnant women and historically has been considered the initial agent of choice when antihypertensive therapy is necessary during pregnancy, the American College of Obstetricians and Gynecologists (ACOG) and other experts currently recommend use of one of several agents (labetalol, nifedipine, or methyldopa) when initiation of antihypertensive therapy is necessary in a pregnant woman. In women who are already receiving antihypertensive therapy prior to pregnancy, ACOG states there are insufficient data to make recommendations regarding the continuance or discontinuance of such therapy; treatment decisions should be individualized in these situations. Antihypertensive therapy can reduce the risk of severe hypertension but has not been shown to prevent the development of preeclampsia. Use of methyldopa in association with careful prenatal management during pregnancy appears to be safe for mother and fetus.
(See Pregnancy under Cautions: Pregnancy, Fertility, and Lactation.)
IV methyldopate hydrochloride has been used for the management of hypertensive emergencies; however, because of the slow onset of action of this drug, other agents (e.g., labetalol, esmolol, fenoldopam, nicardipine, sodium nitroprusside) are preferred.
Methyldopa and methyldopate hydrochloride are not recommended for use in patients with pheochromocytoma.