Included in the formulation
Included in the list (Order of the Government of the Russian Federation No. 2782-r of 30.12.2014):VED
ONLS
АТХ:C.02.C.A.04 Doxazosin
Pharmacodynamics:Doxazosin has an antihypertensive, vasodilating, hypolipidemic, spasmolytic action.
Selectively blocks postsynaptic alpha1-adrenoceptors (affinity to alpha ratio1 /alpha2 less than 600). Reduces the overall peripheral vascular resistance. The antihypertensive effect is partly due to the screening of alpha1adrenoreceptors in the central nervous system. Adrenolitic action is manifested most in the vessels of the kidneys, skin, in less - in the celiac, cerebral and pulmonary vessels. During physical activity, the vasodilating effect is strongly pronounced in the kidneys and skin and less in the muscles. Reduces pre- and postnagruzku, reduces the need for myocardium in oxygen. Systemic arterial pressure decreases moderately without the onset of reflex tachycardia. Reduces the level of total cholesterol, atherogenic fractions of lipoproteins and increases the content high-density lipoproteins. Suppresses the synthesis of collagen in the vascular wall. Inhibits the aggregation of platelets, increases the concentration of tissue activator plasminogen. Reduces the tone of smooth muscle cells stroma and capsules of the prostate, as well as the neck of the bladder.
Pharmacokinetics:When ingestion is absorbed quickly and fairly fully, the simultaneous intake of food slows the absorption by 1 hour. Bioavailability is 62-69%, which reflects the effect of "first passage" through the liver. Cmax is achieved in 2-3 hours. At evening reception time of achievement Cmax lengthened to 5 hours. In plasma, 98-99% of the drug is associated with proteins. Intensively biotransformed in the liver, mainly by demethylation or hydroxylation. Several active metabolites are detected. The final half-life is 19-22 hours. It is included in enterohepatic circulation, and therefore the greater part (63%) is excreted through the intestine with feces, including 5-19% unchanged; through the kidneys only 9% is released.
The effect begins to appear 1-2 hours after ingestion and reaches a maximum after 5-6 hours. The antihypertensive effect develops gradually and lasts up to 24 hours, remaining with the change in the position of the body. Violation of the function of the liver lengthens the action. With prolonged use, blood pressure is reduced by an average of 22/15 mm Hg. Reduces the degree of hypertrophy of the left ventricle.The effect of the first dose in the form of postural hypotension is not very pronounced. Orthostatic hypotension can develop only with prolonged use of high doses. Effective with isolated systolic hypertension and its combination with metabolic disorders (obesity, hyperlipidemia, decreased glucose tolerance). In heart failure, the level of atrial natriuretic peptide release is reduced. It is often used to treat elderly patients with prostate adenoma. Highly effective with its conservative therapy: the effect is assessed from 9 to 18 points of the IPSS (International System for Total Symptom Assessment). A distinct decrease in the severity of obstructive and inflammatory symptoms associated with prostatic hyperplasia (incomplete emptying of the bladder, nocturia, increased urination, burning) and improvement in urodynamics are noted in 66-71% of patients. The improvement usually occurs within 1-2 weeks of treatment, reaches a maximum at 14 weeks and persists for a long time. Reception of the drug in normotonics is not accompanied by a decrease in blood pressure.
The efficacy in the treatment of chronic heart failure and pheochromocytoma is shown.
Indications:Arterial hypertension (monotherapy or in combination with other antihypertensive drugs, including the thiazide diuretics, beta-blockers, calcium channel blockers, ACE inhibitors), benign prostatic hyperplasia (both in the presence of hypertension, and with normal blood pressure).
IX.I26-I28.I27.0 Primary pulmonary hypertension
IX.I10-I15.I15.9 Secondary hypertension, unspecified
IX.I10-I15.I15.0 Renovascular hypertension
XIV.N40-N51.N40 Hyperplasia of the prostate
Contraindications:Stenosis of the aortic and mitral valves, orthostatic hypotension, severe liver function, pregnancy, breast-feeding, age and 18 years of age.
Carefully:It should be borne in mind that the effect of the first reception is especially pronounced against the background of diuretic therapy, and also with a sodium-restricted diet. In elderly people reduce dosage. When driving and production work must consider the possibility of orthostatic hypotension and decreased concentration and reaction rate (usually at the beginning of treatment).With caution apply when there is a violation of the liver (in case of deterioration in the functional status of the liver drug immediately canceled).
Pregnancy and lactation:The action category for the fetus is FDA-C. The drug has strict contraindications for use in pregnancy and lactation.
Dosing and Administration:Inside. Begin treatment with 1 mg per day, once, with a gradual increase (after 1-2 weeks) to 2 mg, then to 4-8 mg. The maximum daily dose for benign prostatic hyperplasia is 8 mg, with arterial hypertension 16 mg for a single dose.
Side effects:The effect of the "first dose" - hypotension, dizziness, syncopal conditions (rarely); postural orthostatic hypotension (with long-term treatment), edema, tachycardia, rhythm disturbances, fatigue, dyspnea, dizziness, headache, nervousness, irritability, pathological drowsiness, blurred vision, rhinitis, xerostomia, abdominal discomfort, nausea, obstipation, pain in chest, cerebrovascular accident, incontinence (rarely).
Overdose:Symptoms: pronounced hypotension, syncopal conditions.
Treatment: it is necessary to give the patient a horizontal position on the back, the head at the level of the trunk, in case of inefficiency - intravenous infusions and the introduction of vasopressor drugs.
Interaction:Doxazosin enhances the antihypertensive effect of antihypertensive drugs. The estrogens, causing fluid retention, contribute to high blood pressure. Non-steroidal anti-inflammatory drugs (especially indomethacin) can reduce the hypotensive effect of doxazosin. Doxazosin reduces the pressor effect of metameninol, ephedrine. It blocks alpha-adrenergic effects of epinephrine, which can lead to severe arterial hypotension and tachycardia. There was no adverse interaction with simultaneous use of doxazosin and thiazide diuretics, furosemide, beta-blockers, calcium channel blockers, ACE inhibitors, antibiotics, oral hypoglycemic agents, indirect anticoagulants and uricosuric agents. Alcohol can increase unwanted reactions.
Special instructions:Before the start of therapy for benign prostatic hyperplasia, it is necessary to exclude its cancer degeneration.