Moderate
Probable
Descrição
Hydroxychloroquine may potentiate the anticoagulant effect of warfarin, raising INR and the risk of bleeding complications.
Mecanismo
The mechanism is not fully established; proposed mechanisms include inhibition of CYP2C9 and CYP3A4, as well as independent antiplatelet properties of hydroxychloroquine.
Significância Clínica
Several case reports and pharmacovigilance analyses document significant INR elevation and bleeding events when hydroxychloroquine is added to warfarin.
Conduta
Monitor INR frequently when starting hydroxychloroquine in warfarin-treated patients; adjust warfarin dose as needed.