May induce convulsions w/ enoxacin hydrate, lomefloxacin, norfloxacin, prulifloxacin, ofloxacin. Increased effect of coumarin anticoagulants eg, warfarin. Increased blood levels of MTX, lithium. Decreased effects of thiazide (eg, hydrochlorothiazide) & loop (eg, furosemide) diuretics. Increased GI reactions w/ corticosteroids eg, methylprednisolone. Increased blood levels w/ CYP2C9 inhibitors (eg, fluconazole). Increased risk of bleeding w/ TCAs, SNRIs, SSRIs, ginkgo & LMWH. Increased risk of cyclosporine nephrotoxicity. Increased risk of acute renal failure w/ tenofovir disoproxil fumarate, tacrolimus. Reduced diuretic effectiveness, hyperkalemia, or possible nephrotoxicity w/ K-sparing diuretics.