Fast acetylators may be more likely to develop hepatitis since hepatotoxicity is caused by the acetylated metabolite of INH, but this remains controversial. However, slow inactivators may develop toxic levels in the presence of impaired renal function. Other Major Uses Isoniazid is used in conjunction with other antituberculosis agents in the treatment of clinical tuberculosis. Isoniazid is usually used alone in certain patients to prevent the development of clinical tuberculosis. The most frequent reactions are those affecting the nervous system and the liver.
Peripheral neuropathy is the most common toxic effect.
A synthetic, isonicotinic acid-derivative. At low temperatures, isoniazid in solution tends to crystallize and should be warmed to room temperature to redissolve the crystals prior to use. Isoniazid preparations should be protected from light, air, and excessive heat. Prophylaxis of mycobacterial infections in immunocompromised patients. Am Fam Physician.