Update on Medical Treatment of Cushing's Syndrome.

First-line treatment of endogenous Cushing's syndrome (CS) is surgical removal of the tumor responsible for cortisol excess. However, medical therapy has an established role in treatment when patients are not surgical candidates or decline surgery, residual or recurrent disease is present and not amenable to repeat resection, and control of hypercortisolism is needed either preoperatively or while awaiting the effects of radiotherapy. The approach to medical therapy should be tailored based on the etiology, degree of hypercortisolism, and patient characteristics. Currently available medical therapy for all etiologies of CS either blocks adrenal production of cortisol or blocks its action at the level of the glucocorticoid receptor. Currently available medical therapy for Cushing's disease (CD) targets the adrenocorticotropic hormone-secreting pituitary tumor through activation of somatostatin and dopamine receptors, alkylating DNA damage, or immune system activation. More focused therapy with greater efficacy and fewer adverse effects is needed, particularly in the case of CD, with potential targets and drugs identified and in development.