Proton pump inhibitors Coumarins

Drugs affected by voriconazole include the following benzodiazepines, calcium channel blockers, cisapride, coumarin anticoagulants, cyclosporine, ergot alkaloids, HMG-CoA reductase inhibitors, NNRTIs, phenytoin, protease inhibitors, pimozide, proton pump inhibitors, quinidine, prednisolone, rifabutin, sirolimus, sulfonylureas, tacrolimus, vinca alkaloids. 

ANTICOAGULANTS-ORAL PROTON PUMP INHIBITORS Possibly t anticoagulant effect when esomeprazole, lansoprazole or omeprazole is added to warfarin Uncertain at present. Omeprazole and lansoprazole are known to induce CYP1A2, which plays a role in activation of coumarins Monitor INR more closely. 1 dose may be required. If 10%, 20% or 30% over range, omit dose for 1, 2 or 3 days respectively consider i maintenance dose by 10%. Regular dosing of a proton pump inhibitor is preferable if affects INR significantly. Not reported with pantoprazole or rabeprazole... 

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