Methyldopa

(MDPA) from the class of phenylethylamines , stimulant, relaxant. Methyldopa is an effective antihypertensive drug. When introduced into the body, it penetrates the blood-brain barrier and is metabolized in the central nervous system , turning first into α-methyldopamine, then into α-methyloradrenaline. The latter, like clonidine , stimulates central a2- adrenergic receptors , inhibits sympathetic impulse, which leads to a decrease in blood pressure. Hypotension is accompanied by a slowdown in heart contractions, a decrease in cardiac output and a decrease in peripheral vascular resistance.

Methyldopa is used as a hypotensive agent in various forms of hypertension, especially in stages IIA and IIB.

The drug is usually well tolerated. Orthostatic hypotension is rare. The drug does not have a direct effect on heart function and usually does not cause a decrease in glomerular filtration rate and a decrease in blood flow in the kidneys. Due to the effect on the adrenergic systems of the brain, the drug often has a sedative effect.

Methyldopa is taken orally in the form of tablets (0.25 g each). Adults are usually prescribed starting from 0.25 g 2-3 times a day. If necessary, increase the dose to 1-1.5-2 g per day. The maximum daily dose for adults is 3 g.

If necessary, children are prescribed starting from 0.01 g (10 mg / kg) per day (in 2–4 doses), then the dose is selected individually depending on the effect. The maximum daily dose for children is 65 mg / kg.

Often, methyldopa is prescribed in combination with saluretics and other antihypertensive drugs, while the dose of methyldopa can be slightly reduced. The combination with saluretics is especially indicated in cases of fluid retention in the body and the appearance of edema.

It should be borne in mind that after cessation of the use of methyldopa, the hypotensive effect stops relatively quickly, the increase in blood pressure usually occurs within 48 hours.

In a number of patients, addiction develops 1–1.5 months after the start of taking the drug and the hypotensive effect decreases; it is advisable in these cases to prescribe methyldopa in combination with other antihypertensive agents and diuretics (hydrochlorothiazide). With combination therapy, the dose is slightly reduced. With a combination of methyldopa in a dose of 0.5 g with 0.05 g (50 mg) of hydrochlorothiazide, drugs can be used once a day.

When using methyldopa, headache, general weakness, dyspeptic symptoms (nausea, vomiting) may develop, redness of the upper half of the body, and an increase in body temperature are possible. In rare cases, the development of reversible leukopenia and thrombocytopenia is possible. Sometimes hemolytic anemia develops. Possible liver dysfunction with the development of cholestasis, jaundice.

Treatment with the drug should be carried out under the control of liver function and blood picture.

Methyldopa is secreted mainly by the kidneys. In case of impaired renal function, the drug should be prescribed in reduced doses. The urine of patients taking methyldopa becomes dark when standing (reaction with the drug and its metabolites).

When prescribing methyldopa to patients of the elderly and senile, care should be taken, since a sharp decrease in blood pressure is possible. It should be prescribed starting with 0.25 g and only gradually increase the dose.

When using the drug, one should take into account its ability to have a sedative effect.

The drug is contraindicated in acute liver diseases (hepatitis, cirrhosis, etc.), with pheochromocytoma, pregnancy. Methyldopa penetrates into the mother’s milk, and therefore it is necessary to carefully weigh the possible positive effect and risk when using the drug in nursing mothers. According to the 2011 Recommendations of the European Society of Cardiology for the Treatment of Cardiovascular Diseases during Pregnancy, α-methyldopa is the drug of choice for long-term use of pregnant hypertension.

Release form: tablets on 0,25 g.