Nidrazid (Isoniazid)

Isoniazid is a pro‑drug that is activated by the bacterial enzyme KatG. Once activated, it inhibits the enzyme InhA, blocking the synthesis of mycolic acids that are essential for the mycobacterial cell wall. This leads to loss of cell wall integrity and bacterial death, particularly in rapidly dividing TB bacilli.

The exact dosage of isoniazid is determined by the prescribing clinician based on the patient’s age, weight, disease form, and renal or hepatic function. Typical adult regimens range from 300 mg to 600 mg once daily, but the prescriber tailors the dose to each individual’s clinical situation.

Safety data for isoniazid in pregnancy are limited, and the drug is classified as pregnancy category unknown. It may be used when the benefits to the mother outweigh potential risks to the fetus. Isoniazid is excreted in breast milk; breastfeeding decisions should be made in consultation with a healthcare professional.

To order Nidrazid, submit an enquiry on the product page at gnhindia.com, specifying the required quantity. GNH India works with hospitals, pharmacies, and procurement teams worldwide, verifies trade or institutional credentials, and then provides pricing, availability, shipping details (including any cold‑chain requirements), and necessary import documentation.

Rifampicin is another cornerstone of TB therapy. While rifampicin has a broad spectrum and induces hepatic enzymes, isoniazid is bactericidal against actively replicating mycobacteria and is especially effective in preventing latent infection. Both drugs are usually combined to enhance efficacy and reduce resistance, but they differ in side‑effect profiles and drug‑interaction potentials.

Nidrazid tablets should be stored at ambient temperature, preferably below 25 °C, in the original packaging to protect them from moisture and direct sunlight. Keep the container tightly closed and out of reach of children. No refrigeration is required for this oral formulation.

Nidrazid is administered orally, usually once daily, with or without food as directed by the prescriber. Patients should swallow the tablet whole with a full glass of water. Adherence to the full prescribed course is essential to achieve cure and prevent resistance.

The most serious adverse events associated with isoniazid are hepatotoxicity, which may present as jaundice, fatigue, or abdominal pain, and severe hypersensitivity reactions, including anaphylaxis. Peripheral neuropathy can also become significant if not prevented with pyridoxine supplementation. Prompt medical evaluation is required if any of these symptoms arise.

Isoniazid should be avoided in individuals with known hypersensitivity to the drug or any of its components. Patients with pre‑existing severe liver disease, acute hepatitis, or uncontrolled peripheral neuropathy should not receive isoniazid without careful medical supervision and risk‑benefit assessment.