Enhanced blood glucose-lowering effect & susceptibility to hypoglycemia w/ oral antidiabetics, ACE inhibitors, pentoxifylline, perhexiline, disopyramide, fibrates, fluoxetine, MAOIs, dextropropoxyphene, salicylates, sulfonamides. Reduced blood glucose-lowering effect & susceptibility to hyperglycemia w/ corticosteroids, danazol, diazoxide, diuretics, glucagon, INH, OCs, phenothiazine derivatives, somatotrophin, sympathomimetics (eg, epinephrine, salbutamol, terbutaline), thyroid hormones, PIs & atypical antipsychotics (eg, olanzapine & clozapine). Potentiated or weakened blood glucose-lowering effect w/ β-blockers, clonidine, lithium salts or alcohol. Occurrence of hypoglycemia sometimes followed by hyperglycemia w/ pentamidine. Reduced signs of adrenergic counter-regulation w/ guanethidine & reserpine.