Warfarin with indomethacin

Indomethacin was used traditionally, but its relative cyclooxygenase-1 (COX-1) selectivity theoretically increases its gastropathy risk. Thus other generic NSAIDs may be preferred. Adverse effects of NSAIDs include gastropathy (primarily peptic ulcers), renal dysfunction, and fluid retention. NSAIDs generally should be avoided in patients at risk for peptic ulcers, those taking warfarin, and those with renal insufficiency or uncontrolled hypertension or heart failure. 

Warfarin, Indomethacin, and Phenylbutazone—these compounds share a single high-affinity site that differs from those described above. They share a secondary site that is identical to or overlaps with that for tryptophan as described above. Salicylate—two primary binding sites. One is identical to or overlaps the tryptophan binding site and the other is identical to or overlaps the high-affinity site for warfarin, indomethacin, and phenylbutazone as described above. 

These studies provide evidence for at least four binding sites in HSA one for tryptophan, that also interacts strongly with many other compounds one that appears to be very specific for bilirubin one high-affinity site for palmitate and one high-affinity site for warfarin, indomethacin, phenylbutazone, and a number of other drugs (i.e. see Ref. 36). Each of these sites appears to be separate and distinct from each of the others. 

Clinically important, potentially hazardous interactions with acenocoumarol, anagrelide, anticoagulants, bismuth, boswellia, calcium hydroxylapatite, capsicum, cholestyramine, desvenlafaxine, devil s claw, dexamethasone, dexibuprofen, dicumarol, etodolac, evening primrose, flunisolide, ginkgo biloba, ginseng, heparin, ibuprofen, indomethacin, ketoprofen, ketorolac, lumiracoxib, methotrexate, methylprednisolone, nilutamide, NSAIDs, phellodendron, prednisone, resveratrol, reteplase, rivaroxaban, sermorelin, sulfites, tirofiban, triamcinolone, urokinase, valdecoxib, valproic acid, verapamil, warfarin... 

Chan T YK. Prolongation of prothronbin time with the use of indomethacin and warfarin. Br J Clin Pract (1997) 51,177-8. 

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