ACTH stimulation test

A test to determine the presence of adrenal insufficiency.

Synthetic adrenocorticotropic hormone (ACTH) is injected intravenously, and the serum cortisol level is measured at timed intervals (30 or 60 min after the injection). A patient with normal adrenal function will respond to the test with increased serum cortisol levels above 18 μg/dl. Serum cortisol levels <15 μg/dl are diagnostic of adrenal insufficiency. The test has been traditionally performed with an injection of 250 μg of ACTH, but studies have shown that 1 μg is an equally effective test dose.

SYN: SEE: Cortrosyn stimulation test; SEE: cosyntropin stimulation test