7 DRUG INTERACTIONS Moderate (e.g., ciprofloxacin) and strong inhibitors of CYP1A2 (e.g., fluvoxamine) increase systemic exposure of pirfenidone and may alter the adverse reaction profile of pirfenidone. Consider dosage reduction with use of ciprofloxacin. Moderate CYP1A2 Inhibitors Concomitant administration of pirfenidone and ciprofloxacin (a moderate inhibitor of CYP1A2) moderately increases exposure to pirfenidone [see Clinical Pharmacology ( 12.3 )] .
Source: FDA drug label - pirfenidone capsule, 267 mg