Phenytoin, phenobarbital, carbamazepine, rifampicin, and antithyroid drugs increase the clearance of hydrocortisone and reduce its half-life. Hydrocortisone may weaken the effect of anticoagulants and antidiabetics. In combination with anticholinesterases, corticosteroids can cause muscle weakness in patients with myasthenia gravis. Systemic glucocorticoid therapy increases the risk of hypokalemia in patients receiving diuretics or amphotericin B. Glucocorticoids may increase the risk of anti-inflammatory analgesic-induced peptic ulcer.