Which of the following ATT has maximum CSF penetration?
Isoniazid (lsonicotinic acid hydrazide, H): Pharmacokinetics: INH is completely absorbed orally and penetrates all body tissues, tubercular cavities, placenta and meninges. It is extensively metabolized in liver; most impoant pathway being acetylation-metabolites are excreted in urine. The rate of INH acetylation shows genetic variation. There are either: Fast acetylators (30--40% of Indians) half life of iNH 1 hr. Slow acetylators (60-70% of Indians) half lifeof iNH 3 hr The propoion of fast and slow acetylators differs in different pas of the world. However, acetylator status does not matter if INH is taken daily, but biweekly regimens are less effective in fast acetylators. Isoniazid induced peripheral neuritis appears to be more common in slow acetylators. ESSENTIALS OF MEDICAL PHARMACOLOGY K.D.TRIPATHI SIXTH EDITION PAGE NO:740
Streptomycin
INH
Rifampicin
Ethambutol
Chemotherapy