Isoniazid

Antibacterial agent used primarily as a tuberculostatic. Isoniazid remains the treatment of choice for tuberculosis. Isoniazid is an antimycobacterial.
Isoniazid is a synthetic derivative of nicotinic acid with antimyco bacterial properties. Although mechanism of action is still unclear, isoniazid appears to block the synthesis of mycolic acids, major components of the mycobacterial cell wall.this agent is only active against actively growing mycobacteria because, as a pro-drug, it requires activation in susceptible mycobacterial species. Isoniazid also interferes with mycobacterial metabolism of vitamin b6. Resistance occurs due to decreased bacterial wall penetration.