Table 2.

Dosage, action and adverse reactions of first-line and selected second-line anti-TB drugs

Drug	Daily dose and range (mg/kg body weight), maximum dose (mg)	Role in the treatment strategy	Adverse reactions
Rifampicin	10 (8–12), 600	Most important anti-TB drug Bactericidal and sterilizing, rapidly rendering the patient non-infective Allows shortening of therapy to half	Hepatotoxicity Rash Hematologic
Isoniazid	5 (4–6), 300	Bactericidal Potent early bactericidal activity	Hepatotoxicity Rash Neuropathy Lupus-like reaction Anemia
Pyrazinamide	25 (20–30), 2000	Bactericidal early effect Allows shortening of therapy by 3 months in DS-TB	Hepatotoxicity Rash Arthralgias
Ethambutol	15 (15–20), 1600	Bacteriostatic The least effective drug, but protects against resistance	Optic neuritis (can cause blindness) Rash
Streptomycin	15, 1000	Bactericidal	Nephrotoxicity Vestibular toxicity Ototoxicity
Kanamycin	15, 1000	Bactericidal	Nephrotoxicity Vestibular toxicity Ototoxicity
Levofloxacin	750–1000 mg/day	Strong anti-TB activity	Nausea Tremulousness, insomnia Arthralgias Rare QTC prolongation, tendon rupture
Ethionamide	15 (15–20), 1000 frequently divided	Bacteriostatic	Gastrointestinal upset and nausea Hepatotoxicity Reversible hypothyroidism

Abbreviation: DS-TB, drug-susceptible TB.