Which TB drug can worsen gout due to hyperuricemia?

• A. Ethambutol
• B. Pyrazinamide
• C. Isoniazid
• D. Rifampin

Answer: (B)

Pyrazinamide is the TB drug most linked to worsening gout due to hyperuricemia. The key idea is that some TB medications can affect how the kidneys handle uric acid. Pyrazinamide, and its metabolite pyrazinoic acid, interferes with the kidney’s ability to excrete uric acid by competing for the same tubular secretion pathways in the proximal tubule. This reduces uric acid clearance, elevating serum urate levels and increasing the risk of gout flares, especially at higher doses or in people with preexisting hyperuricemia.

The other drugs don’t prominently cause gout through increasing uric acid. Ethambutol is mainly associated with optic neuritis; isoniazid can cause hepatotoxicity and neuropathy; rifampin can cause hepatotoxicity and alters drug metabolism via enzyme induction and changes in bodily fluids.