Beschreibung
Azithromycin can potentiate the anticoagulant effect of warfarin, leading to elevated INR and increased bleeding risk during and shortly after the antibiotic course.
Mechanismus
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.
Klinische Bedeutung
Case reports and pharmacovigilance data document supratherapeutic INR elevations; major bleeding has been reported.
Maßnahmen
Monitor INR within 3–5 days of starting and after completing azithromycin; adjust warfarin dose if INR rises above target range.
Medizinischer Haftungsausschluss
This content is for educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making medication decisions.