Included in the formulation
АТХ:C.02.D.B.02 Hydralazine
Pharmacodynamics:Hydralazine has a vasodilating, hypotensive effect. Decreases the afterload on the heart.It changes the intracellular calcium metabolism, suppresses the contractility of the smooth muscles of the vessels, expands the arterioles and (to a small extent) the veins, reduces the peripheral resistance.
Pharmacokinetics:Absorbed by 90%. Bioavailability is from 10 (for "fast acetylators") to 31% (for "slow acetylators"). The connection with plasma proteins is 87%. Vd - 1,5 ± 1 l / kg. Biotransformiruetsya in the liver to active metabolites. The half-life is 3-7 hours; with chronic renal failure (with creatinine clearance less than 20 ml / min) - up to 16 hours; increases with chronic heart failure. Clearance - 56 ± 13 ml / (min ± kg), decreases with chronic heart failure. Eliminated by the kidneys is 52-90% (in unchanged form, 2-4% of the substance is taken with ingestion, 11-14% with intravenous administration), with feces about 10%.
Indications:Arterial hypertension, hypertensive crisis, congestive heart failure with high afterload, eclampsia.
IX.I10-I15.I10 Essential [primary] hypertension
IX.I10-I15.I15 Secondary Hypertension
IX.I30-I52.I50 Heart failure
XV.O10-O16.O15 Eclampsia
Contraindications:Hypersensitivity, severe atherosclerosis, mitral heart defects.
Carefully:Aortic aneurysm, cerebrovascular insufficiency, phenylketonuria, systemic lupus erythematosus, peripheral neuropathy, active autoimmune processes, renal failure.
Pregnancy and lactation:Recommendations of the FDA category C. Insufficiently well studied in pregnant women. Pregnant women have developed anxiety, epigastric pain, fever, headache, hypotension, nausea and vomiting, palpitations, decreased placental perfusion, tachycardia, tremor. In newborns from mothers who took hydralazine - thrombocytopenia, leukopenia, petechial rash, hematomas; the symptoms disappeared within 1-3 weeks. With the delay of intrauterine development of the fetus development of fetal distress was noted. The risk of fetal distress development is increased in the case of hydralazine without volume preload (infusion therapy). It is recommended that hydralazine Only in those cases where the expected benefit to the mother exceeds the potential risk to the fetus.
It penetrates into breast milk in small amounts, complications are not registered. The American Academy of Pediatrics hydralazine compatible with breastfeeding.Apply with lactation strictly according to the doctor's prescription.
Dosing and Administration:Inside, after a meal, starting with 10-25 mg 2-4 times a day, with a gradual increase to 100-200 mg per day (in 4 divided doses). Higher doses: single dose - 100 mg, daily - 300 mg.
Side effects:Allergic reactions, skin vasculitis, angina, swelling, lupus syndrome, anorexia, nausea, vomiting, constipation, diarrhea, lymphadenopathy, peripheral neuritis, headache, tachycardia, hypotension, face redness, dyspnea, lacrimation, nasal congestion.
Overdose:Headache, excessive lowering of blood pressure, tachycardia, myocardial ischemia, myocardial infarction, increased sweating, shock.
Treatment is symptomatic.
Interaction:Diazoxide, other antihypertensive drugs - increase the hypotensive effect of hydralazine.
Nonsteroidal anti-inflammatory drugs, especially indomethacin, estrogens, sympathomimetic drugs - weaken the hypotensive effect of hydralazine.
Special instructions:When monotherapy occurs reflex tachycardia, the shock volume of blood rises, fluid retention develops (as a result of activation of the sympathoadrenal system and renin-angiotensin-aldosterone system). Rational combinations with diuretics, sympatholytic drugs and β-blockers. In elderly people and people with coronary heart disease, it is possible to develop the phenomenon of "stealing" (do not inject intravenously!). Orthostatic hypotension is rare (due to selective expansion of arterioles).
Monitoring of titer of antinuclear antibodies, blood pressure, general blood test (hydralazine should be canceled with a decrease in the amount of hemoglobin, erythrocytes, development of leukopenia, agranulocytosis, purpura).