Description of the active substance:
This information is a reference and it is not enough that the drug has been prescribed by a doctor ..
PHARMACHOLOGIC EFFECT
Selective competitive blocker of postsynaptic? 1- adrenoreceptors. Causes the expansion of peripheral vessels, which leads to a decrease in OPSS and a decrease in blood pressure. Promotes an increase in the ratio of HDL / total cholesterol, a decrease in the total level of triglycerides and cholesterol.
With long-term use, regression of left ventricular hypertrophy is observed, suppression of platelet aggregation and an increase in the content of plasminogen activator in tissues. The blockade? 1- adrenoreceptors located in the stroma and capsule of the prostate gland in the neck of the bladder leads to a decrease in resistance and pressure in the urethra, a decrease in resistance in its internal opening. Improves urodynamics and reduces the manifestations of benign prostatic hyperplasia.
PHARMACOKINETICS
After oral administration, it is well absorbed from the digestive tract. C max in plasma is achieved through 1.5-3.6 hours. Binding to plasma proteins is 98-99%.Intensively metabolized in the liver. T 1/2 is 19-22 hours. It is excreted mainly through the intestines in the form of metabolites, 5% - in unchanged form; 9% is excreted by the kidneys.
INDICATIONS
Arterial hypertension. Benign prostatic hyperplasia (symptomatic treatment).
DOSING MODE
The initial dose is 1 mg / day. After 1-2 weeks, depending on the clinical situation, the dose can be increased to 2 mg / day, and then after 1-2 weeks - up to 4 mg, 8 mg or 16 mg / day to achieve the optimal therapeutic effect. On average, the daily dose is 2-4 mg.
The maximum dose: 16 mg / day.
SIDE EFFECT
From the cardiovascular system: orthostatic reactions (including faints), tachycardia, arrhythmia, peripheral edema.
From the side of the digestive system: nausea.
From the side of the central nervous system: dizziness, headache, fatigue, irritability, asthenia, drowsiness.
Other: rhinitis.
CONTRAINDICATIONS
Severe hepatic impairment; urinary tract infections; anuria; progressive renal failure; arterial hypotension with orthostatic disorders (including in anamnesis); arterial hypotension (refers only to the indication of benign prostatic hyperplasia); concomitant obstruction of the upper urinary tract; chronic urinary tract infections; stones in the bladder; obstructive disorders of the digestive tract; esophageal obstruction; decrease in the diameter of the lumen of the digestive system of any degree; lactose intolerance, lactase deficiency or glucose-galactose malabsorption (due to the presence of lactose in the formulation); children and adolescents under 18; lactation period (breastfeeding); hypersensitivity to quinazoline derivatives (eg, prazosin, terazosin, doxazosin).
As a monotherapy: patients with bladder overflow; anuria with or without progressive renal failure.
PREGNANCY AND LACTATION
Adequate and strictly controlled studies of the safety of doxazosin during pregnancy and lactation (breastfeeding) have not been conducted. The application is only possible in cases where the potential benefit to the mother exceeds the potential risk to the fetus or child.
APPLICATION FOR VIOLATIONS OF THE FUNCTION OF KIDNEYS
Use with caution for violations of liver function.
APPLICATION FOR CHILDREN
Clinical experience with doxazosin in children is absent.
APPLICATION IN ELDERLY PATIENTS
After taking doxazosin in the initial dose, elderly persons may develop orthostatic hypotension (the phenomenon of the first dose), especially when standing. In this regard, the initial dose is recommended before bedtime.
SPECIAL INSTRUCTIONS
With caution should be used for pulmonary edema caused by stenosis of the mitral valve or aortic stenosis; heart failure with increased cardiac output; right ventricular failure due to pulmonary embolism or exudative pericarditis; left ventricular failure with low filling pressure; disorders of cerebral circulation; in elderly patients;simultaneous use with PDE-5 inhibitors (threat of symptomatic arterial hypotension); with hepatic insufficiency; during pregnancy; when performing an operation to remove cataracts.
After taking doxazosin in the initial dose, orthostatic hypotension may develop (the phenomenon of the first dose), especially when standing. More often this condition is observed in patients with hypovolemia, sodium deficiency, in the elderly. In this regard, the initial dose is recommended before bedtime.
Clinical experience with doxazosin in children is absent.
Impact on the ability to drive vehicles and manage mechanisms
When taking doxazosin, especially at the beginning of treatment, care should be taken when performing work that requires an increased rate of psychomotor reactions, due to the possible development of drowsiness, dizziness.
DRUG INTERACTION
With simultaneous use with antihypertensive drugs, mutual enhancement of effects is possible.
When used simultaneously with PDE-5 inhibitors (sildenafil, tadalafil, tardenafil, vardenafil), some patients may develop symptomatic arterial hypotension.
Do not take doxazosin simultaneously with other blockers? 1- adrenoreceptors.
At simultaneous application with blockers of calcium channels there is a certain risk of development of the expressed arterial hypotension.
At simultaneous application with nitrates, means for the general anesthesia, tricyclic antidepressants, ethanol the hypotensive effect strengthening probably is possible.
With the simultaneous use of drugs that affect the metabolic rate in the liver, it is possible to slow or accelerate the metabolism of doxazosin.
Estrogens and sympathomimetic agents can reduce the hypotensive effect of doxazosin. Eliminating the alpha-adrenostimulating effects of epinephrine (adrenaline), doxazosin can lead to tachycardia and arterial hypotension.
