CPT® Code 80420

The CPT® Code 80420 refers to a laboratory test known as the dexamethasone suppression panel, which is conducted over a 48-hour period. This test is specifically designed to evaluate the function of the adrenal glands in response to the administration of adrenocorticotropic hormone (ACTH) suppression. The primary purpose of the dexamethasone suppression test is to assist in the diagnosis of Cushing syndrome, a condition characterized by excessive cortisol production, and to help identify the underlying cause of this hormonal imbalance. The procedure involves a comprehensive urine collection that begins after the first morning void, with strict requirements for the handling and storage of the urine samples to ensure accurate results. Throughout the 48-hour testing period, patients are required to take oral dexamethasone at specified intervals, and both urine and blood samples are collected to measure cortisol levels. The results of this panel provide critical information regarding adrenal function and are essential for determining the appropriate clinical management of patients suspected of having Cushing syndrome.