Isoniazid + Ethambutol (Isoniazidum + Aethambutolum)

Pharmacodynamics Pharmacokinetics Indications Carefully Contraindications Dosing and Administration Side effects
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Clinical and pharmacological group: & nbsp

Other synthetic antibacterial agents

Included in the formulation
  • Protubetam®
    pills inwards 
    FARMASINTEZ, JSC (Irkutsk)     Russia
  • Phthisoetham®
    pills inwards 
    AKRIKHIN HFK, JSC     Russia
    • Included in the list (Order of the Government of the Russian Federation No. 2782-r of 30.12.2014):

    VED

    АТХ:

    J.04.A.M.03   Isoniazid in combination with ethambutol

    Pharmacodynamics:

    Combined anti-tuberculosis drug.

    Isoniazid

    Inhibits the enzymes necessary for the synthesis of mycolic acids, which are the main structural fragments of the cell walls of mycobacterium tuberculosis.

    The most intensive synthesis of mycolic acids is carried out in growing cells, so isoniazid has a bactericidal action on them, and bacteriostatic action on mature cells.

    The high selectivity of the chemotherapeutic effect of isoniazid is due to the fact that there are no mycolic acids in the tissues of the macroorganism, as well as in other microorganisms.

    Ethambutol

    Blocking the incorporation of mycolic acids into the cell wall, suppresses synthesis of mycobacterium membrane. Operates bacteriostatically in relation to Mycobacterium tuberculosis, M. bovis and nontuberculous mycobacteria (M. kansasii).

    Pharmacokinetics:

    Isoniazid

    After oral administration, the empty stomach is completely absorbed in the gastrointestinal tract.The maximum concentration in blood plasma is achieved in 1-4 hours. The connection with plasma proteins is from 1 to 10%.

    Therapeutic effect develops after the reception. Metabolism in the liver by acetylation to inactive metabolites, penetrates the placental barrier, is excreted in breast milk.

    The rate of acetylation of the drug is genetically determined, so the half-life of isoniazid varies.

    Half-life for "fast acetylators" is 1 hour, for "slow" - 3 hours. Elimination by the kidneys.

    Ethambutol

    After oral administration, an empty stomach is absorbed up to 80% in the gastrointestinal tract. The maximum concentration in the blood plasma is reached after 2 hours. The connection with plasma proteins is 10-40%.

    Metabolism in the liver.

    Half-life is 3.3-3.5 hours. Elimination with feces and kidneys.

    Indications:

    It is used for the treatment of tuberculosis of all forms and localizations. It is used for the prevention and anti-relapse therapy of tuberculosis.

    ICD-10

    I.A15-A19.A15   Tuberculosis of respiratory organs, confirmed bacteriologically and histologically

    I.A15-A19.A17   Tuberculosis of the nervous system

    I.A15-A19.A18   Tuberculosis of other organs

    Contraindications:

    Stomach and duodenal ulcer, cardiovascular insufficiency, bronchial asthma, liver cirrhosis, epilepsy, propensity to convulsive seizures, diseases of the eyes, violations of the liver and kidneys, gout, myxedema, eye diseases, age to 13 years, pregnancy and lactation , individual intolerance.

    Carefully:

    Chronic renal failure.

    Pregnancy and lactation:

    Recommendations for FDA - Category C. Contraindicated in pregnancy and lactation.

    Dosing and Administration:

    Inside after a meal, 1 time per day for 5-10 mg / kg of body weight for 3-4 months of intensive care, then in a day. The dose in terms of isoniazid depends on the stage of the disease and individual tolerability.

    Side effects:

    Isoniazid

    Central and peripheral nervous system: memory disorders, insomnia, mental disorders disorders, euphoria, peripheral neuritis, muscle twitching.

    The cardiovascular system: pain in the heart.

    Digestive system: medicinal hepatitis.

    Dermatological reactions: itching, skin rash.

    Sense organs: optic neuritis - blurred vision or loss of vision.

    Reproductive system: gynecomastia, menorrhagia.

    Allergic reactions.

    Ethambutol

    Central and peripheral nervous system: confusion, headache, hallucinations, disorientation, peripheral neuropathy.

    Digestive system: sensation of metallic taste in the mouth, anorexia, nausea, vomiting, gastralgia.

    Dermatological reactions: dermatitis, rash.

    Sense organs: retrobulbar neuritis with decreased visual acuity, narrowing of the visual fields, violation of color perception (red and green), central or peripheral scotoma.

    Allergic reactions.

    Overdose:

    Metabolic acidosis, neurotoxic effect: dysarthria, lethargy, disorientation, hyperreflexia, convulsions, coma.

    Treatment is symptomatic. Effective hemodialysis.

    Interaction:

    Strengthens the action indirect hemocoagulants.

    Inhibits the metabolism of benzodiazepines, phenytoin and theophylline.

    Simultaneous use with paracetamol and other hepatotoxic substances increases the risk of toxic hepatonecrosis.

    Antatsidnye means slow down and reduce the absorption of isoniazid in the intestine, it is recommended to take them with an interval of 1 hour.

    With the simultaneous use of certain fish species (tuna, sardinella) and cheeses (Swiss), there may be a hyperemia of the skin, itching, headache due to the isoniazid suppression of monoamine oxidase and diaminoxidase activity in the blood plasma and a violation of the metabolism of histamine and tyramine.

    Aluminum hydroxide reduces the absorption of ethambutol.

    Special instructions:

    It is recommended to use reliable contraceptive methods during taking the drug.

    In the treatment of ethanol, driving and working with moving machinery.

    Instructions
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