Methyldopa

Pharmacological properties

The drug acting on the central mechanisms of regulation of hell. penetrates the blood-brain barrier; it is metabolized with the formation of alpha-methylnoradrenaline, which stimulates the postsynaptic α-adrenergic receptors of the brain stem neurons in the central nervous system, which leads to inhibition of the vasomotor center. the hypotensive effect with prolonged use of the drug is mainly associated with a decrease in opss, the minute volume of blood does not change. increases glomerular filtration rate and renal blood circulation, reduces plasma renin level. It also causes a moderate decrease in cardiac output and heart rate. the effect of the drug appears 2 hours after application and lasts 24–48 hours.

After oral administration, about 50% of the drug is absorbed in the digestive tract. Protein binding - up to 20%. Up to 10% of the dose taken is metabolized to form alpha-methyldopa and alpha-methyl-radrenaline. It is allocated mainly by kidneys. About 70% of the absorbed drug is excreted in the urine in the form of methyldopa and its sulfoconjugates.

With prolonged use, the drug may accumulate in the body. The elimination half-life is no more than 8 hours; with renal failure - increases. After ingestion, the complete elimination of the drug occurs after 36 hours. It is removed during hemodialysis, peritoneal dialysis.

Indications

Mild and moderate ag, ag in pregnant women.

Application

The dose is set individually. as a rule, the initial dose of methyldopa for adults is 250 mg (1 tablet) 2-3 times a day for the first 2 days.

Then the daily dose is increased by 250 mg (1 tablet) sequentially every 2 days until an adequate level of blood pressure reduction is achieved. If necessary, increase the dose to 1-1.5 g / day. The maximum daily dose for adults is 3 g (12 tablets).

If necessary, children are prescribed Dopegit, starting with a dose of 10 mg / kg body weight (in 2–4 doses), in the future the dose is selected individually, depending on the effect obtained. The maximum daily dose for children is 65 mg / kg body weight.

Contraindications

Dopegit tablets should not be used if:

• allergies to any component that is part of the drug;

• active hepatitis and / or liver failure, cirrhosis;

• autoimmune hemolytic anemia;

• pheochromocytomas;

• hyperprolactinemia;

• porphyria;

• depression.

Side effects

From the cardiovascular system: peripheral edema, orthostatic hypotension, bradycardia.

From the side of the central nervous system: headache, dizziness, weakness, drowsiness, rarely - Parkinsons syndrome, hallucinations.

From the digestive tract: nausea, vomiting, dry mouth, diarrhea, constipation, pancreatitis, impaired liver function, jaundice, colitis.

From the hemopoietic system: rarely - leukopenia and thrombocytopenia, autoimmune hemolytic anemia.

From the endocrine system: gynecomastia, galactorrhea, decreased libido, impotence.

Allergic reactions: exanthema.

Rarely - fever, myalgia, arthralgia, lupus syndrome.

special instructions

With extreme caution, the drug should be used in patients with cerebrovascular accident; history of depression; Parkinsons disease (possibly exacerbation).

In case of kidney disease, before the use of Dopegitis, an examination should be carried out to determine the presence of renal failure.

During the first 1-3 months of treatment, it is recommended to periodically monitor the hemogram and the level of hepatic transaminases in the blood serum.

After the first 6-10 weeks of treatment, it is necessary to exclude the possibility of autoimmune hemolytic anemia (Coombs test), which must be repeated every 6 months to 1 year with long-term treatment.

In the treatment with methyldopa, the appearance of a positive catecholamine test is possible, indicating the possibility of developing pheochromocytoma.

The introduction of Dopegitis at a dose of ≥750 mg / day can also lead to the appearance of a positive porphobilinogen test. In connection with the effect of the drug on the water balance, peripheral edema may occur, which sometimes requires the appointment of diuretics. Since edema is the most common side effect when using the drug Dopegit, during treatment it is necessary to ensure control of the patient’s body weight, drinking and dietary regimen.

With general anesthesia, the narcotic effect may increase.

During pregnancy, women taking Dopegit, stop taking it is not necessary. The use of Dopegitis in this case should be carefully weighed taking into account the correlation of benefits for the mother with the potential risk to the child.

Methyldopa passes into breast milk, therefore, when prescribing Dopegit, the patient must stop breast-feeding.

During treatment, alcohol should be avoided.

It is necessary to refrain from potentially hazardous activities that require concentration, including driving.

Interactions

Caution should be exercised when taking dopegitis in combination with any of the following drugs:

• levodopa, levadopa / cardidopa - an increase in antihypertensive effect is possible;

• drugs belonging to the group of MAO inhibitors (for example, phenelzine, transcypromine) - it is possible to increase hypotension or hypertension with psychomotor agitation;

• drugs for the treatment of patients with depression (for example, tricyclic antidepressants) - a decrease in the antihypertensive effect, the appearance of tachycardia, agitation, headache;

• diuretics, apressin, calcium antagonists, ACE inhibitors, β-adrenergic receptor blockers, α-adrenergic receptor blockers or other antihypertensive drugs, as well as anesthetics enhance the effect of Dopegit;

• digoxin - the appearance of bradycardia, asystole;

• iron preparations weaken the effect of Dopegitis;

• indomethacin and other NSAIDs reduce the antihypertensive effect of Dopegitis;

• lithium - an increase in lithium toxicity is possible;

• alcohol and drugs that cause depression of the central nervous system increase the depressive effect;

• anticoagulants derivatives of coumarin, indion increase anticoagulant effect;

• anorexigenic drugs weaken the effect of Dopegitis;

• sympathomimetics dopamine, mesatone enhance the effect of Dopegit.

The combination of Dopegitis with tranquilizers causes an increase in the antihypertensive effect. When urine is alkylated, the concentration of Dopegitis in the blood increases, with acidization, the effect decreases.

The use of Dopegit in combination with any of these drugs can change their effect on the body or be dangerous to the body.

Overdose

Symptoms: severe arterial hypotension, tremor, bradycardia, atony of the stomach, vomiting, mental retardation.

Treatment: gastric lavage (if the drug has been taken recently); if detoxification is carried out with a significant delay, the use of hemodialysis is more effective than the forced diuresis method. According to the indications, plasma-replacing solutions, adrenomimetics (for example, epinephrine) are prescribed. In case of an overdose of Dopegit tablets, you should immediately consult a doctor at the nearest emergency department or hospital.

Storage conditions

At a temperature of 15–25 ° C.