Isoniazid

General characteristics. Structure:

Active ingredient: 100 mg, 150 mg, 200 mg or 300 mg of an isoniazid.

Excipients: stearate calcium monohydrate, polysorbate-80 (twin-80), кросповидон (коллидон CL-M), potato starch.

The antimicrobic drug having high bacteriological activity concerning tuberculosis mycobacteria (causative agents of tuberculosis). On other widespread causative agents of infectious diseases has no the expressed chemotherapeutic effect.

Pharmacological properties:

Pharmacodynamics. The antituberculous remedy, works bakteritsidno, synthesis of the mikoliyevy acids which are the most important component of a cell wall of mycobacteria oppresses and also synthesis of DNA of a bacterial cell oppresses. It is especially active concerning the fast-breeding microorganisms (including intracellularly located).

Pharmacokinetics. The isoniazid is quickly and fully absorbed at intake. The maximum concentration in a blood plasma is reached in 1-2 hours. It is well distributed on all organism, getting into all fabrics and liquids, passes through GEB. Gets through a placental barrier and into breast milk. Is exposed to metabolism in a liver to inactive products. It is excreted generally by kidneys: during 24 h 75-95% of drug are removed.

Indications to use:

Tuberculosis (any localization, at adults and children, treatment and prevention). It is applied as a part of a combination therapy.

Route of administration and doses:

Inside, after food, on 0.6-0.9 g/days, the maximum single dose – 0.6 g, daily – 0.9 g; to children - on 5-15 mg/kg/days, frequency rate of reception - 1-2 times a day, the maximum dose – 0.5 g/days. For the purpose of prevention - inside, on 5-10 mg/kg/days in 2 receptions within 2 months. During pregnancy and at a severe form of a pulmonary heart, the expressed atherosclerosis, the ischemic heart disease and arterial hypertension should not appoint more than 10 mg/kg in doses.

Features of use:

Due to the different speed of metabolism before use of an isoniazid it is reasonable to determine the speed of its inactivation (by dynamics of maintenance in blood and urine). At a bystry inactivation the isoniazid is applied in higher doses. Alcoholism, a liver failure, a renal failure, convulsive attacks, dekompensirovanny diseases of CCC (HSN, stenocardia, arterial hypertension), a hypothyroidism, pregnancy — it is not necessary to appoint higher than 10 mg/kg in a dose.

Side effects:

Dizziness; seldom — fatigue, irritability, sleeplessness, paresthesias, perifericheskaya a neuropathy, an optic neuritis, a polyneuritis, change of mood. At patients with epilepsy attacks can become frequent. Increase of attacks of stenocardia, tachycardia, increase in the ABP. Nausea, vomiting, gastralgia, toxic hepatitis. Skin rash, an itch, a hyperthermia, irritation in the place of an injection. Very seldom — a gynecomastia, a menorrhagia, tendency to bleedings and hemorrhages, an arthralgia. Treatment: peripheral polyneuropathy (B6, B1, B12 vitamins, ATP, glutaminic acid, niacinamide, massage, physiotherapeutic procedures); spasms (B6 vitamin in oil — 200-250 mg, in/in 40% dextrose solution — 20 ml, 25% in oil sulfate magnesium solution — 10 ml, diazepam). The abnormal liver function demands a dose decline of an isoniazid and purpose of methionine, lipamidum, ATP, B12 vitamin. At emergence of symptoms of toxic hepatitis drug is cancelled. At emergence of allergic reactions treatment by an isoniazid prer howl and carry out dissensibiliziruyushchy therapy.

Interaction with other medicines:

Cycloserinum strengthens adverse central effects of an isoniazid. Raises a rifampicin hepatotoxic. At a combination with paracetamol also nephrotoxicity increases gepato-. Ethanol raises a hepatotoxic of an isoniazid and accelerates his metabolism. The isoniazid reduces theophylline metabolism that can lead to increase in its concentration in blood. The antiacid HP which are (especially Al3+-containing) slow down absorption and reduce concentration of an isoniazid in blood (antacids should be accepted not earlier than in 1 h after reception of an isoniazid). The probability of side effects decreases at a combination with B6 vitamin and glutaminic acid.

Contraindications:

Hypersensitivity, medicinal hepatitis and liver failure, liver diseases in the period of an aggravation.

Overdose:

Symptoms: dizziness, a dysarthtia, slackness, a disorientation, a hyperreflexia, a peripheral polyneuropathy, an abnormal liver function, a metabolic acidosis, a hyperglycemia, a glucosuria, a ketonuria, spasms (in 1-3 h after drug use), a coma.

Storage conditions:

In the dry, protected from light place, at a temperature not over 25 ºС.

Issue conditions:

According to the recipe

Packaging:

Tablets 0.1, 0.15, 0.2, 0.3 of of 10 blisters on 10 tablets in cardboard packaging; tablets of 0.1 g on 100 or on 50 tablets in bank from dark glass