Prazosin Hydrochloride Tablets

Pharmacological action: 1. Prazosin hydrochloride is a selective postsynaptic a1 receptor blocker and a quinazoline derivative. It can relax vascular smooth muscle, dilate peripheral blood vessels, reduce peripheral vascular resistance, and lower blood pressure. 2. This product dilates arteries and veins, reduces cardiac preload and afterload, reduces left ventricular end-diastolic pressure, improves cardiac function, and has a rapid onset of action in the treatment of heart failure, reaching a peak in 1 hour and lasting for 6 hours. 3. This product has little effect on renal blood flow and glomerular filtration rate, and can relieve urination difficulties in patients with prostatic hyperplasia by blocking a1 receptors in the bladder neck, prostate capsule and glands, and urethra. 4. Animal experiments show that most drugs are combined with a1 acid glycoprotein, and only 5% of the drugs exist in the blood in a free form. The concentration in the lungs, heart, blood vessels and other parts is higher, but lower in the brain. 5. This product does not affect a2 receptors, rarely causes reflex tachycardia when lowering blood pressure, has little effect on cardiac output, and does not increase renin secretion. Long-term use has no effect on lipid metabolism. Carcinogenicity, Mutagenesis and Reproductive Toxicity Rats were given 225 times the highest recommended human dose (20 mg per day) of prazosin hydrochloride for 18 months, and no carcinogenic effect was found; in genetic toxicology studies, no gene mutation was found in prazosin hydrochloride. Rats given 225 times the highest recommended human dose (75 mg/kg) of prazosin hydrochloride had reduced reproductive capacity; while 75 times the maximum recommended human dose (25 mg/kg) had no effect on reproduction. Dogs and rats were given 25 mg/kg per day for one year, and testicular atrophy and necrosis occurred; while the above changes were not found when given 10 mg/kg per day (30 times the highest recommended human dose). 105 patients who took prazosin hydrochloride for a long time monitored the secretion of 17-ketosteroids and found no abnormal changes; 27 patients who took the drug for up to 51 months also found no drug-induced sperm morphological changes. When pregnant rats, rabbits and monkeys were given 225 times or 12 times the highest recommended human dose, respectively, no abnormalities in appearance, internal organs or bones were found in the fetuses.

Main ingredients: The main ingredient of this product and its chemical name are: 1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-(2-furoyl)piperazine hydrochloride.

This product is white tablets.

Used for mild to moderate hypertension.

Oral administration, 0.5mg-1mg at a time, 2-3 times a day (the first dose is 0.5mg, taken before bedtime). Gradually adjust to 6mg-15mg a day according to the efficacy, taken in 2-3 times. The efficacy will not be further increased after the daily dose exceeds 20mg.

1. This product can cause syncope, which is mostly caused by postural hypotension. It occasionally occurs when the ventricular rate is 100-160 beats/min. It usually occurs 30-90 minutes after the first dose or when used in combination with other antihypertensive drugs. It is more likely to occur in patients with a low-sodium diet and those taking beta-blockers. If the first dose is changed to 0.5 mg and taken before bedtime, this adverse reaction can be prevented or alleviated; if diuretics are stopped the day before this drug is given, it can also be alleviated. This side effect is self-limiting and will not recur in most cases. 2. Dizziness and drowsiness may occur after the first dose. Driving and dangerous work should be avoided on the first day after the first dose or increase in dosage. Dizziness may occur when the body position changes from lying to standing, which can be avoided by getting up slowly. In addition, dizziness can occur after drinking, standing for a long time, exercising, or daytime exercise.

1. When used with calcium antagonists, the antihypertensive effect is enhanced and the dosage must be adjusted appropriately. The same precautions should be taken when used with other antihypertensive drugs or diuretics. 2. When used with thiazide diuretics or beta-blockers, the antihypertensive effect is enhanced and water and sodium retention may be reduced. When used together, the dosage should be adjusted to obtain the minimum effective dose of each drug. 3. When used with non-steroidal anti-inflammatory analgesics, especially with indomethacin, the antihypertensive effect of this product can be weakened. 4. When used with sympathomimetic drugs, the antihypertensive effect of this product is weakened. 5. No adverse side effects occur when this drug is used in combination with the following drugs: digoxin; insulin; sulfonylurea hypoglycemic drugs: including hypoglycemic spirit, tolbutamide, chlorpropamide, tolazamide; sedatives: including chlordiazepoxide and diazepam; probenecid; antiarrhythmic drugs: including procainamide, atenolol, quinidine; analgesics, antipyretics and anti-inflammatory drugs: including propoxyphene, aspirin, indomethacin, phenylbutazone.

Keep in a light-proof and airtight container.

1mg

Hangzhou Conba Pharmaceutical Co., Ltd.

• Founded in:

  2000-03-27

• Address:

  No. 568, Binkang Road, Changhe Street, Binjiang District, Hangzhou City, Zhejiang Province

• Tax NO.:

  91330108716159914E

• Registered Funds:

  380 million yuan

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