Potentiated blood glucose-lowering effect w/ insulin & other oral antidiabetics, MAOIs, ACE inhibitors, miconazole, anabolic steroids & male sex hormones, para-aminosalicylic acid, chloramphenicol, high-dose parenteral pentoxifylline, coumarin derivatives, phenylbutazone, azapropazone, oxyphenbutazone, cyclophosphamide, probenecid, disopyramide, quinolones, fenfluramine, salicylates, fenyramidol, sulphinpyrazone, fibrates, sulfonamides, fluoxetine, tetracyclines, guanethidine, tritoqualine, ifosfamide, trofosfamide. Weakened blood glucose-lowering effect w/ acetazolamide, laxatives (after protracted use), barbiturates, high-dose nicotinic acid, corticosteroids, oestrogens & progestogens, diazoxide, phenothiazines, diuretics, phenytoin, epinephrine & other sympathomimetic agents, rifampicin, glucagons, thyroid hormones. Potentiated or weakened blood glucose-lowering effect w/ H
2-receptor antagonists, β-blockers, clonidine, guanethidine, reserpine, acute & chronic alcohol intake. Potentiated or weakened effects of coumarin derivatives.