Pirroxan, tablets 15 mg 50 pcs

Pharmacotherapeutic group:

Apha-adrenoblocker

ATC code: C02CA

Pharmacological properties

Pharmacodynamics

Proxan has hypotensive and antipruritic effects. It blocks postsynaptic α₁ and presynaptic α₂ adrenoreceptors, regardless of their localization. It has peripheral and central effects. Reduces the sensitivity of adrenoreceptors to adrenaline by changing the permeability of cell membranes. Reduces the intensity of stimulation of hypothalamic structures, reducing the release of tropic hormones, hormones of peripheral glands. Weakens the transmission of adrenergic vasoconstrictor impulses, eliminates spasm and dilates peripheral vessels, especially arterioles and precapillaries. Improves blood supply to muscles, skin, mucous membranes. It suppresses excitability of the diencephalic structures of the brain and regulates the tone of the sympathoadrenal system.

Pharmacokinetics

The drug has been found to be well absorbed in the gastrointestinal tract, but the effective concentration is reached only after 30-40 minutes and remains for 3-4 hours. Binding to plasma proteins is weak. The drug has a large volume of distribution, it quickly penetrates into various tissues and fluids, including the cerebrospinal fluid. It penetrates well through histohematic barriers, including the blood-brain barrier. It is selectively retained in hypothalamus, whose posterior region contains predominantly noradrenergic neurons. It is excreted mainly by the kidneys. About 70% of the administered dose is excreted by the kidneys in the first 24 hours.

In animal experiments with intraperitoneal administration no half-life was established, with less than 5% of the administered dose remaining in the blood plasma 1 hour after administration, and only traces after 2 hours. In the brain after 1 hour, 22% of the maximum concentration was detected, and after 2 hours, 6% of the maximum concentration. Also in experiments with labeled carbon proxane it was shown that its metabolic products are able to stay for a long time (up to 10 days) in various organs and tissues (plasma, brain, liver, kidneys).

Indications

– Somatoform vegetative dysfunction of the sympathoadrenal type, including increased blood pressure (as symptomatic treatment in the complex therapy);

– allergic dermatitis (as symptomatic treatment in the complex therapy to relieve itching).

Active ingredient

Composition

Active substance:

Proxan hydrochloride – 15 mg;

Supplementary substances:

ludipress® [lactose monohydrate – 78.3 mg,

povidone K-30 – 2.95 mg,

crospovidone – 2.95 mg] – 84, 2 mg;

magnesium stearate – 0.8 mg.

How to take, the dosage

In somatoform vegetative dysfunction of the sympatho-adrenal type in the complex therapy is prescribed 15-30 mg (1-2 tablets) orally 2-3 times a day. The duration of treatment is determined by the attending physician.

Interaction

It enhances the effect of neuroleptics (phenothiazine derivatives, butyrophenone, diphenyl butylpiperidine, thioxanthene);

An adverse effect of novocainamide may decrease cardiac stroke volume;

concomitant use with adrenaline may pervert its action – development of depressor effect instead of pressor effect;

concomitant use of proxan with hypotensive agents leads to mutual potentiation of their blood pressure lowering effects.

Special Instructions

The peculiarities of action of the drug at the first dose

When taking the first dose of the drug, a sharp decrease in blood pressure, fainting, headache, weakness, palpitations and deterioration of the subjective state (“first dose phenomenon”) may occur, which is not a reason to cancel the drug, since this effect disappears when taking it again. Drowsiness and rapidly passing sensation of numbness of the tongue are also noted. In addition, it is recommended to monitor the concentration of glucose in the blood because of a possible increase in the level of endogenous insulin. Therefore, it is necessary to begin treatment under a physician’s supervision with the minimum effective dose and to observe bed rest for 6-8 hours after taking the drug.

The effect of the drug on the ability to drive vehicles, mechanisms

When using the drug it is not recommended to drive vehicles and perform potentially dangerous activities requiring increased concentration and quick psychomotor reactions.

Contraindications

Hypersensitivity to the active ingredient or excipients of the drug;

Developed atherosclerosis;

Developed cerebrovascular insufficiency (incl.ч. strokes, history of transient ischemic attacks;

ischemic heart disease (functional class II-IV),

Side effects

Cardiovascular system: bradycardia, arterial hypotension, occurrence of angina attacks in predisposed patients, orthostatic hypotension, arrhythmias, dizziness, skin hyperemia, nasal congestion.

Gastrointestinal tract: diarrhea, increased secretion of hydrochloric acid in the stomach.

If any of the side effects listed in the instructions worsen, or if you notice any other side effects not listed in the instructions, tell your doctor.

Overdose

Symptoms: bradycardia, orthostatic collapse, sharp decrease of blood pressure.

Pregnancy use

The use is contraindicated during pregnancy and while breastfeeding.

Similarities