May cause hyperglycemia w/ all other medicines to treat diabetes, ACE inhibitors, disopyramide, fluoxetine, fibrates, MAOIs, pentoxifylline, propoxyphene, salicylates, sulfonamides. May cause hyperglycemia w/ corticosteroids, danazol, diazoxide, diuretics, glucagon, INH, oestrogens & progestogens, phenothiazine derivatives, somatropin, sympathomimetics (eg, epinephrine, salbutamol, terbutaline), thyroid hormones, atypical antipsychotics (eg, clozapine, olanzapine), PIs. Enhanced/reduced effects w/ β-blockers, clonidine, lithium salts & alcohol. Pentamidine may cause hypoglycemia, sometimes followed by hyperglycemia. May weaken or suppress entirely the 1st warning symptoms of hypoglycemia w/ β-blocker, clonidine, guanethidine & reserpine.