Etambutol (ethambutol) tablets 0.4 №50

Description

Etambutol Composition
active substance: ethambutol;

1 tablet contains ethambutol hydrochloride (in terms of 100% dry matter) – 400 mg;

excipients: calcium hydrogen phosphate dihydrate, povidone, sodium lauryl sulfate, talc, magnesium stearate.

Etambutol Dosage form
Pills.

Basic physical and chemical properties: white tablets, round with a flat surface, beveled and scored.

Pharmacotherapeutic group
Antimicrobial agents for systemic use. Means that act on mycobacteria. Anti-tuberculosis drugs. Ethambutol.

ATX code J04A K02.

Pharmacodynamics
Ethambutol has a pronounced bacteriostatic effect against Mycobacterium tuberculosis, as well as some atypical mycobacteria (M.avium, M.kansasii, M.xenopi). The drug inhibits the reproduction of mycobacteria resistant to streptomycin, isoniazid, paraaminosalicylic acid (PAS), ethionamide, kanamycin and other anti-tuberculosis drugs. The mechanism of action of ethambutol after its penetration into mycobacterium is associated with inhibition of the synthesis of RNA and proteins, the ability to interact with ions of bivalent biometals (copper, magnesium), disruption of the ribosome structure and inhibition of the intensity of lipid metabolism. About 1% of patients have primary drug resistance. With monotherapy of tuberculosis, rapid tolerance develops.

Pharmacokinetics
When administered orally, 75-80% of the drug is absorbed from the digestive tract. Simultaneous food intake enhances and accelerates the absorption process. The maximum concentration of ethambutol in the blood is reached after about 2 hours and is 4-5 μg / ml when the drug is administered at a dose of 25 mg / kg and 8-9 μg / ml when the drug is administered at a dose of 50 mg / kg. Plasma protein binding depends on the dose taken and is 10-40%. The half-life (T½) is 3.3-3.5 hours. A feature of the pharmacokinetics of ethambutol is that it selectively accumulates in erythrocytes (the concentration is 2 times higher than in blood plasma). Ethambutol passes into the cerebrospinal fluid, through the placenta and into breast milk. The drug is excreted mainly unchanged in the urine. Approximately 10-20% of ethambutol is excreted in the feces as inactive metabolites (aldehydes, dicarboxylic acids). The appointment of ethambutol in case of impaired renal function can lead to its accumulation in the body.

Etambutol Indications
Treatment of all forms of pulmonary and extrapulmonary tuberculosis (in combination with other anti-tuberculosis drugs).

Contraindications
Hypersensitivity to the drug;
optic neuritis;
cataract;
inflammatory eye diseases;
diabetic retinopathy;
gout;
severe renal failure, chronic renal failure;
situations when it is impossible to check the state of vision (serious condition, mental disorders).