isoniazid (Nydrazid, Laniazid, INH are all discontinued brands) (cont.)

Pharmacy Author:
Medical and Pharmacy Editor:

Pyridoxine (vitamin B6), 10-50 mg/day, decreases the risk of neural side effects.

The rate at which Isoniazid is eliminated by the liver is race-dependent. Thus, 60% of African Americans and whites eliminate Isoniazid slowly compared with only 10%-20% of Asians. Individuals who eliminate Isoniazid slowly are more prone to develop hepatitis and neural side effects with long-term use of Isoniazid.

Other important side effects of Isoniazid include:

PRESCRIPTION: Yes

GENERIC AVAILABLE: Yes

PREPARATIONS: Tablets: 100 or 300 mg. Syrup: 50 mg per teaspoonful. Injection: 100 mg/ml.

STORAGE: Tablets and syrup should be stored at room temperature, 15 C - 30 C (59 F - 86 F).

DOSING: The recommended dose for latent tuberculosis 300 mg daily for 9 months. Active tuberculosis is treated with 5 mg/kg up to 300 mg daily or 15 mg/kg up to 900 mg 1-3 times weekly. It is best to take Isoniazid on an empty stomach for maximum absorption into the body, but if it causes abdominal discomfort, it may be taken with food or with a non-aluminum antacid such as Tums or Titralac. (Aluminum-containing antacids bind to the Isoniazid in the intestine and prevent its absorption.)

Medically Reviewed by a Doctor on 2/11/2015


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