In TB drug therapy, hepatotoxicity is commonly caused by which drugs, and how is it managed?

• A. INH, PZA, and rifampin; stop offending drugs and monitor LFTs, then reintroduce sequentially
• B. Ethambutol and streptomycin; continue therapy with no changes
• C. Clofazimine; adjust dose
• D. Bedaquiline; reduce dose

Answer: (A)

Hepatotoxicity during TB therapy is most commonly linked to the three first-line drugs: isoniazid, pyrazinamide, and rifampin. When liver injury is suspected—through symptoms like jaundice, nausea, abdominal pain, or elevated liver enzymes—the offending drugs are stopped to allow the liver to recover. After liver tests return to normal, treatment is restarted one drug at a time with careful monitoring of liver function. This sequential reintroduction helps identify which drug caused the injury while keeping the other effective medications in use to complete therapy. The other drugs mentioned are not the usual culprits for hepatotoxicity, so they aren’t the focus when this specific toxicity is being managed.