- Description, composition and properties
- Release form and price
- Indications for use
- Dosage and features of administration
- Interaction with other drugs
- Contraindications
- Adverse reactions
- Overdose
- Reviews
One of the modern medications for high blood pressure with proven effectiveness is Doxazosin tablets. We will talk further about the properties, composition, indications for use, main contraindications and features of the use of the drug in hypertensive patients.
Brief information about the medicine
Release form
The drug is produced in the form of tablets that are intended for oral administration. Round tablets are packaged in blisters, jars or bottles. Available in packs of 30, 50 or 100 tablets. The kit includes instructions for using Doxazosin.
Compound
The drug includes:
- doxazonin mesylate – the main substance;
- lactose;
- starch;
- sodium glycolate;
- magnesium salt of stearic acid;
- sodium dodecyl sulfate;
- microcrystalline cellulose.
Packaging of Doxazosin tablets
pharmachologic effect
Doxazosin tablets have hypolipidemic, antihypertensive, antispasmodic and vasodilating effects.
Manufacturer
The drug is produced in Russia and Canada:
- pharmaceutical enterprise Obolenskoye;
- NIOPIK State Research Center;
- zio-Health;
- Skopinsky Pharmaceutical Plant;
- Nu-Pharm Inc.
Terms and conditions of storage
It is recommended to store the medication out of the reach of children and in a dark place. The optimal storage temperature should be between 15-25 degrees. It is recommended to store in a dry place.
The shelf life is 2 years. After the expiration date, the drug is disposed of.
Conditions for dispensing from a pharmacy
The tablets can be bought at a pharmacy without a prescription from a doctor.
Price
The cost of Doxazosin tablets is 100-300 rubles. The price varies depending on the number of tablets in the package.
Analogs
Doxazosin, analogues of which can be found on the pharmacological market, can be replaced only as prescribed by a doctor. The most common analogues:
- Cardura;
- Artesin;
- Kamiren.
Such drugs have a similar principle of action and are widely used to treat arterial hypertension and benign prostatic hyperplasia.
Doxazosin, instructions for use of which are in each package, can be replaced with other alpha-blockers - drugs such as Omnic, Tamsulosin, Terazosin, Alfuzosin, Silodosin.
Pharmacodynamics: effect on blood pressure
The drug belongs to the pharmacological class of alpha-blockers. The drug blocks alpha receptors, lowers vascular tone, and reduces triglycerides and cholesterol.
How do alpha blockers work?
Doxazosin reduces blood pressure, lipid concentrations, relieves spasms and dilates blood vessels. The drug inhibits platelet aggregation, increases the level of plasminogen, and decreases the tone in cellular tissues, the prostate gland, and the bladder. The action of the drug is aimed at reducing overall vascular resistance, lowering blood pressure, pressure in the urethra, and reducing sphincter resistance.
After taking the medication, the pressure decreases after 2-6 hours, the effect of one tablet lasts for a day. With prolonged use, left ventricular hypertrophy may decrease.
Doxazosin tablets composition
One tablet contains:
Active substance: doxazosin mesylate in terms of doxazosin 1 or 2 or 4 mg.
Excipients: lactose, calcium phosphate, Kollidon 30, sodium dodecyl sulfate, calcium stearate, talc.
Photo of the packaging of doxazosin tablets 0.002 g with the composition indicated
Photo of the packaging of doxazosin tablets 0.004 g with the composition indicated
Description
Tablets are white or white with a creamy tint, round, biconvex in shape.
Pharmacotherapeutic group: alpha1 - adrenergic blocker
ATX code: CQ2CA04
Pharmacological properties
Pharmacodynamics
Doxazosin is a selective competitive blocker of postsynaptic alpha1-adrenoreceptors. By reducing vascular muscle tone, doxazosin reduces total peripheral vascular resistance, which leads to a decrease in blood pressure (BP). After a single dose of the drug, the maximum hypotensive effect is observed in the period from 2 to 6 hours, and in general the hypotensive effect persists for 24 hours. During treatment with doxazosin in patients with arterial hypertension, there are no differences in blood pressure values in the standing and lying positions. Effective for arterial hypertension, including those accompanied by metabolic disorders (obesity, decreased glucose tolerance).
Reduces the risk of developing coronary heart disease.
Taking the drug in “normotensive” patients is not accompanied by a decrease in blood pressure.
With long-term use of doxazosin in patients, there is no change in tolerance to the therapeutic antihypertensive effect.
During treatment with doxazosin, a decrease in the concentration of triglycerides and total cholesterol in the blood plasma is observed. At the same time, there is a slight (4-13%) increase in the HDL/total cholesterol ratio. With long-term treatment with doxazosin, regression of left ventricular hypertrophy, suppression of platelet aggregation and an increase in the content of active plasminogen in tissues are observed.
Due to the fact that doxazosin blocks alpha1-adrenergic receptors located in the stroma and capsule of the prostate gland and in the neck of the bladder, there is a decrease in resistance and pressure in the urethra, and a decrease in the resistance of the internal sphincter. Therefore, the administration of doxazosin to patients with symptoms of benign prostatic hyperplasia leads to a significant improvement in urodynamics and a decrease in the manifestations of symptoms of the disease. It has an effect in 66-71% of patients, the onset of action is after 1-2 weeks of treatment, maximum after 14 weeks, the effect lasts for a long time.
Pharmacokinetics
After oral administration in therapeutic doses, doxazosin is well absorbed from the gastrointestinal tract, absorption - 80-90% (simultaneous food intake slows down absorption by 1 hour), time to reach maximum concentration - 3 hours, when taken in the evening - 5 hours. Bioavailability - 60 -70% (presystemic metabolism). Communication with blood plasma proteins is about 98%. Elimination from blood plasma occurs in 2 phases, with a final half-life of 19-22 hours, which allows the drug to be administered once a day. Rapidly metabolized in the liver by o-demethylation and hydroxylation.
It is excreted through the intestines, mainly in the form of metabolites, up to 65%; only 5% is excreted unchanged in the urine.
Studies of the pharmacokinetics of doxazosin in elderly patients and in patients with kidney disease did not reveal significant pharmacokinetic differences.
Instructions for use and dosage
According to the instructions, you can take the tablets at any time of the day, regardless of meals. But doctors recommend taking the drug before meals, since food slows down the absorption process. In the evening, the absorption time of the substance increases, so it is recommended to take the tablets once a day in the morning. Doxazosin should be taken whole with water if you have high blood pressure.
Doxazosin should be taken for blood pressure as prescribed by a doctor, who draws up an individual treatment regimen for each patient. The initial daily dosage is 1 mg. It is recommended to take the first tablet before bedtime, since after the first tablet your blood pressure may drop significantly, down to critical levels.
The dosage can be gradually increased if the prescribed dose does not produce the required hypotensive effect. It is allowed to increase the dose no earlier than 7-14 days after starting therapy with Doxazosin. Once the therapeutic effect is achieved, the dosage is gradually reduced, leaving the maintenance dose at 1 mg.
For prostate hyperplasia and normal blood pressure, the daily dosage is 2-4 mg. The maximum daily dose of the alpha-blocker Doxazosin for adenoma is 8 mg.
Composition and release form
Doxazosin is available in the form of tablets, the color of which varies from white to light cream. The medicine is sold in packages with contour cells. The number of tablets may vary, from 7 pieces to 50 pieces. The medicine can also be sold in cardboard packs; the number of tablets in this case can vary from 10 to 100 pieces per package. The price for Doxazosin will also differ accordingly.
The main active component of the drug is doxazosin; its content in one tablet is equal to one, two or four mg, depending on the concentration. Auxiliary ingredients are milk sugar, starch, magnesium, sodium glycolate, sodium.
special instructions
Patients with diagnosed diseases should take this blood pressure medication with caution:
- swelling of the pulmonary tissue, which is caused by stenosis of the mitral or aortic valve;
- ventricular dysfunction syndrome;
- heart failure.
The drug should be used strictly as prescribed by the doctor.
Patients with impaired liver function should take the drug under medical supervision if medications that affect liver function are also prescribed. If the condition worsens, it is necessary to stop therapy with the drug Doxazosin for blood pressure.
When starting to use Doxazosin for high blood pressure, it is necessary to refrain from driving or performing work that requires concentration, as psychomotor reactions may slow down.
Alcohol increases the likelihood and degree of development of adverse drug reactions.
Contraindications
Situations when the drug Doxazodine cannot be used include those under 18 years of age, when all systems are not yet fully formed and the active substance of this drug can have a negative effect on the reproductive and cardiac systems.
Also, contraindications to taking the drug include the following conditions and situations:
- the presence of serious damage to the kidneys and liver;
- severe and acute heart failure;
- the presence of malignant neoplasms in the body;
- obstruction of the bile ducts with stones in them;
- presence of a stone in the bladder.
Also, the drug cannot be prescribed for the treatment of women and adolescents with mitral valve stenosis and existing serious concomitant diseases.
Side effects
Main side effects:
- headaches;
- prostration;
- dizziness;
- rapid fatigue;
- sleepy state;
- nasal congestion;
- gagging.
When using Doxazosin with high blood pressure, additional adverse reactions from the cardiovascular system may occur:
- increased heart rate;
- heart rhythm disturbance;
- painful manifestations in the sternum;
- heart attack;
- angina pectoris;
- cerebrovascular diseases.
In rare cases, doxazosin from pressure leads to the development of additional reactions:
- skin rashes;
- yellowing of the skin;
- difficulty defecating;
- blood from the nose;
- involuntary urination;
- constant feeling of hunger;
- strong drop in pressure.
Most often, adverse reactions develop at the beginning of drug therapy, then the body adapts and health returns to normal.
Side effects are more likely to occur when you start taking the drug
What does Doxazosin treat?
The drug is prescribed to combat benign prostatic hyperplasia (adenoma). In this case, the presence or absence of arterial hypertension does not affect the therapeutic effect. The therapeutic effect of the drug is observed when used as a measure to prevent coronary myocardial disease. The medication helps reduce the number of cholesterol plaques on the walls of blood vessels.
When taken with antibacterial drugs (especially Amoxicillin), it is used to treat purulent endocarditis and to prepare for surgery to remove pheochromocytoma (adrenal tumor).
The drug is prescribed to combat benign prostatic hyperplasia (adenoma).
