Definition of isoniazid in English:

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Pronunciation: /ˌīsəˈnīəzəd/


A synthetic compound used as a bacteriostatic drug, chiefly to treat tuberculosis.
  • A derivative of nicotinic acid and hydrazine; chemical formula: C5H5NCONHNH2.
Example sentences
  • Even the addition of a bactericidal drug streptomycin to isoniazid only resulted in a marginal increase to 49 per cent.
  • Most patients with latent tuberculosis are treated with isoniazid administered daily for nine months.
  • Drug susceptibility patterns to isoniazid and rifampicin by the conventional method showed complete association with E-test results.


1950s: from iso- 'equal' + ni(cotinic) + (hydr)azine + -ide.

For editors and proofreaders

Syllabification: i·so·ni·a·zid

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