Moderate
Probable
विवरण
Azithromycin can potentiate the anticoagulant effect of warfarin, leading to elevated INR and increased bleeding risk during and shortly after the antibiotic course.
तंत्र
Proposed mechanisms include inhibition of CYP1A2 and possible disruption of gut flora that synthesize vitamin K2 (menaquinones), reducing vitamin K availability for clotting factor synthesis.
नैदानिक महत्व
Case reports and pharmacovigilance data document supratherapeutic INR elevations; major bleeding has been reported.
प्रबंधन
Monitor INR within 3–5 days of starting and after completing azithromycin; adjust warfarin dose if INR rises above target range.