Methazide (Tablets) Instructions for Use

ATC Code

J04AK (Other antituberculosis drugs)

Active Substance

Metazide (Rec.INN WHO registered)

Clinical-Pharmacological Group

Antituberculosis drug

Pharmacotherapeutic Group

Agents active against mycobacteria; antituberculosis agents; other antituberculosis agents

Pharmacological Action

Antituberculosis agent, possesses bacteriostatic activity against Mycobacterium tuberculosis.

It is especially active against actively dividing Mycobacterium tuberculosis (including those located intracellularly).

It disrupts the synthesis of phospholipids, forms intra- and extracellular chelate complexes with divalent ions, inhibiting oxidative processes and the synthesis of nucleic acids.

Resistance develops rapidly during monotherapy.

Pharmacokinetics

Absorption is high.

C_max in blood plasma is reached after 1 hour.

It penetrates well into various organs and tissues, including the cerebrospinal fluid.

It penetrates the placental barrier and is secreted into breast milk.

It is metabolized in the liver with the formation of inactive acetylated metabolites.

T_1/2 is about 6 hours.

It is excreted mainly by the kidneys in the form of metabolites and unchanged, a small amount is excreted by the intestines.

Indications

Tuberculosis: all forms and localizations (in combination with other antituberculosis drugs).

ICD codes

Dosage Regimen

Administer orally with meals to minimize gastrointestinal adverse reactions.

For adult patients, the standard dosage is 500 mg twice daily. The maximum daily dose for adults must not exceed 2 grams.

For pediatric patients over 3 years of age, calculate the dose based on body weight at 20-30 mg/kg/day. The maximum daily dose for children is 1 gram.

Divide the total calculated daily dose for children into two or three separate, equally sized administrations.

Always use Metazide as part of a combination antituberculosis therapy regimen to prevent the rapid development of bacterial resistance. Monotherapy is not recommended.

The typical treatment course for active tuberculosis is a minimum of 6 months. The exact duration of therapy must be determined by a physician based on clinical response and disease localization.

Concomitantly administer pyridoxine (Vitamin B6) prophylactically to reduce the incidence and severity of neuropathic adverse effects, such as peripheral neuritis.

Regularly monitor liver function tests and ophthalmological examinations, including funduscopy, throughout the treatment period due to the risk of hepatotoxicity and optic neuritis.

Adjust the dosing schedule in cases of missed doses to maintain consistent therapeutic levels; do not double a dose to compensate for a missed one.

Adverse Reactions

From the nervous system: headache, dizziness, cardialgia, sleep disturbance, impaired coordination of movements, increased fatigue, depressive states, psychoses, memory disorder, euphoria, increased frequency of epileptic seizures in patients with epilepsy.

From the sensory organs: peripheral neuritis and optic neuritis, optic nerve atrophy.

From the digestive system: nausea, vomiting, dry mouth, gastralgia, hepatitis, impaired liver function.

Allergic reactions: skin rash.

Other: gynecomastia (in men), menorrhagia (in women), agranulocytosis, leukopenia, thrombocytopenia, methemoglobinemia, muscle twitching, impaired renal function.

Contraindications

Hypersensitivity to metazide; angina pectoris, decompensated heart defects, epilepsy, tonic-clonic seizures (in history), organic lesions of the central and peripheral nervous system, hepatic insufficiency, non-tuberculous kidney diseases, impaired renal function; pregnancy, breastfeeding period; children under 3 years of age.

Use in Pregnancy and Lactation

Contraindicated for use during pregnancy and lactation (breastfeeding).

Use in Hepatic Impairment

Contraindicated for use in hepatic insufficiency.

Use in Renal Impairment

Contraindicated for use in non-tuberculous kidney diseases, impaired renal function.

Pediatric Use

Contraindicated for use in children under 3 years of age.

Special Precautions

During treatment, periodic examination of the fundus is necessary.

To prevent the development of neuritis, vitamins B₁ and B₆ should be prescribed simultaneously with metazide.

Effect on ability to drive vehicles and machinery

During treatment, side effects of metazide that affect the speed of psychomotor reactions are possible. This should be taken into account by persons engaged in potentially hazardous activities that require increased concentration and speed of psychomotor reactions.

Drug Interactions

It enhances (mutually) the effect of other antituberculosis drugs.

Storage Conditions

Store at 2°C (36°F) to 25°C (77°F). Keep in original packaging, protected from light. Keep out of reach of children.

Dispensing Status

Rx Only

Important Safety Information

This information is for educational purposes only and does not replace professional medical advice. Always consult your doctor before use. Dosage and side effects may vary. Use only as prescribed.