INH

Abbreviation with 2 meanings

INH
Stands forIsoniazid
Meanings2
CategoriesMedical

INH has two meanings. It stands for Isoniazid (drug) or Inhalation (medication route).

Meanings of INH at a glance

#INH stands forContext
1IsoniazidMedical › Drug
2InhalationMedical › Medication Route

1. Isoniazid

Medical · Drug Abbreviations

First-line antibiotic for tuberculosis, used alone for latent TB infection and with other drugs for active TB. INH is the standard abbreviation in TB clinics, lab reports and guidelines.

Example: INH 300 mg plus pyridoxine 25 mg daily x 9 months for latent TB.

The abbreviation comes from its chemical name, isonicotinic acid hydrazide. Pyridoxine (vitamin B6) is added to prevent peripheral neuropathy. Liver toxicity rises with age and alcohol use, so monthly symptom checks are standard. Because INH also abbreviates "inhalation", some safety experts prefer writing "isoniazid".

2. Inhalation

Medical · Medication Route Abbreviations

Route in which a drug is breathed into the lungs as an aerosol or powder from a metered-dose inhaler, dry-powder inhaler or nebulizer, acting directly on the airways with lower systemic exposure than tablets.

Example: Albuterol HFA 2 puffs INH q4-6h PRN wheeze.

On medication records INH may mean the route, but in pharmacy it is better known as the abbreviation for the tuberculosis drug isoniazid, so the full word "inhaled" or "inhalation" is safer. Only about 10 to 20 percent of an inhaled dose typically reaches the lungs with an inhaler, less without good technique or a spacer.

More drug abbreviations

  • HCT – Hydrocortisone
  • HCTZ – Hydrochlorothiazide
  • HQ – Hydroquinone
  • IFN – Interferon
  • ISDN – Isosorbide dinitrate
  • ISMN – Isosorbide mononitrate
  • IVIG – Intravenous immunoglobulin
  • IVMP – Intravenous methylprednisolone

See all 170 drug abbreviations →

More medication route abbreviations

  • IJ – Injection
  • IL – Intralesional
  • IM – Intramuscular
  • IN – Intranasal
  • inj – Injection
  • IO – Intraosseous
  • IP – Intraperitoneal
  • IT – Intrathecal

See all 41 medication route abbreviations →

Edited by the AbbreviationList.com team. Spotted an error or a missing meaning? Contact us.

This entry is for general education and is not medical advice. Abbreviation use varies between institutions; always confirm in context.