Glimepiride: Metabolism is influenced w/ CYP2C9 inducers (eg, rifampicin) or inhibitors (eg, fluconazole). Potentiated blood glucose-lowering effect w/ insulin & oral antidiabetic products, ACE inhibitors, allopurinol, anabolic steroids, male sex hormones, chloramphenicol, coumarin anticoagulants, cyclophosphamide, disopyramide, fenfluramine, fenyramidol, fibrates, fluoxetine, guanethidine, ifosfamide, MAOIs, miconazole, fluconazole, para-aminosalicylic acid, pentoxifylline (high-dose parenteral), phenylbutazone, probenecid, quinolone antibiotics, salicylates, sulfinpyrazone, clarithromycin, sulfonamide, tetracyclines, tritoqualine, trofosfamide, sympathetic inhibitor. Weakened blood glucose-lowering effect w/ acetazolamide, barbiturates, corticosteroids, diazoxide, diuretics, epinephrine (adrenaline) or sympathomimetics, glucagons, laxatives (long-term use), nicotinic acid (high dose), estrogens, progestogens, phenothiazines, phenytoin, rifampicin, thyroid hormones. Potentiated or weakened blood glucose-lowering effect w/ H
2-antagonists, clonidine, reserpine. Reduced glucose tolerance w/ β-blockers. Reduces or blocks signs of adrenergic counter regulation to hypoglycemia w/ sympatholytic drugs (eg, β-blockers), clonidine, guanethidine, reserpine. Acute & chronic alcohol intake may potentiate or weaken blood glucose-lowering action of glimepiride. Potentiates or weakens effects of coumarin derivatives. Metformin HCl: Lactic acidosis may occur w/ iodinated contrast materials; antibiotic having strong nephrotoxicity (gentamicin). Potentiated effect w/ insulin, sulfonamides, sulfonylureas products, α-glucosidase inhibitor (alkalosis), anabolic steroids, guanethidine, salicylates (aspirin), β-blockers (propranolol), MAOIs, angiotensin-reversion enzyme inhibitor. Weakened effect w/ epinephrine, sympathomimetics, corticosteroids, thyroid hormones, estrogens, OCs, thiazide & other diuretics, pyrazinamide, INH, nicotinic acid, phenothiazines, phenytoin, Ca channel blockers, β
2-agonists (eg, salbutamol, formoterol).