Isoniazid, marketed under other names including isonicotinylhydrazide (INH) and Hydra, is an antibiotic used as a first-line agent in the prevention and treatment of both latent and active tuberculosis.[1] It is effective against mycobacteria, particularly Mycobacterium tuberculosis. It is also active against some atypical strains like M. kansasii and M. xenopi.[2] Isoniazid is an organic compound that is available in tablet, syrup, and injectable forms.[3][4][5]

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| isonicotinohydrazide |
| Trade names | Hydra, Isovit, Laniazid, Nydrazid |
| AHFS/Drugs.com | monograph |
| MedlinePlus | a682401 |
| Pregnancy category |
C |
| Legal status | prescription only (US) |
| Routes of administration |
oral, intramuscular, intravenous |
| Protein binding | Very low (0-10%) |
| Metabolism | liver; CYP450: 2C19, 3A4 inhibitor |
| Biological half-life | 0.5-1.6h (fast acetylators), 2-5h (slow acetylators) |
| Excretion | urine (primarily), feces |
| CAS Number | 54-85-3 |
| ATC code | J04AC01 |
| PubChem | CID: 3767 |
| DrugBank | DB00951 |
| ChemSpider | 3635 |
| UNII | V83O1VOZ8L |
| KEGG | D00346 |
| ChEBI | CHEBI:6030 |
| ChEMBL | CHEMBL64 |
| NIAID ChemDB | 007657 |
| Formula | C6H7N3O |
| Molecular mass | 137.139 g/mol |
| SMILES[show] | |
| InChI[show] | |