Hypoglycemic action may be potentiated by certain drugs, including NSAIDs & other highly protein-bound drugs eg, salicylates, sulfonamides, chloramphenicol, coumarin derivatives, probenecid, MAOIs, β-adrenergic blocking agents. Reduced hypoglycemic effect w/ thiazides & other diuretics, corticosteroids, phenothiazines, estrogens, OC, nicotinic acid, sympathomimetics, thyroid hormones & INH.