Glimepiride: May potentiate blood glucose-lowering effect w/ insulin & other oral antidiabetics, ACE inhibitors, anabolic steroids & male sex hormones, chloramphenicol, coumarin derivatives, cyclophosphamide, disopyramide, fenfluramine, fenyramidol, fibrates, fluoxetine, guanethidine, ifosfamide, MAOIs, miconazole, fluconazole, para-aminosalicylic acid, pentoxifylline (high dose parenteral), phenylbutazone, azapropazone, oxyphenbutazone, probenecid, quinolones, salicylates, sulfinpyrazone, clarithromycin, sulfonamide antibiotics, tetracyclines, tritoqualine, trofosfamide. May reduce blood glucose-lowering effect w/ acetazolamide, barbiturates, corticosteroids, diazoxide, diuretics, epinephrine (adrenaline) & other sympathomimetic agents, glucagon, laxatives (after protracted use), nicotinic acid (in high doses), oestrogens & progestogens, phenothiazines, phenytoin, rifampicin, thyroid hormones. May potentiate or reduce blood glucose-lowering effect w/ β-blockers, clonidine, reserpine & alcohol. May potentiate or weaken effect of coumarin derivatives. Metformin: Alcohol intoxication. Renal failure w/ intravascular administration of iodinated contrast agents. Caution use w/ glucocorticoids, β
2-agonists & diuretics for their intrinsic hyperglycaemic activity. Decreased blood glucose levels w/ ACE inhibitors. Decreased anticoagulant effect of phenprocoumon. Reduced hypoglycaemic effect w/ levothyroxine.