Adrenocorticotropic Hormone (ACTH) Blood In a.m.: 25-100 pg/ml In p.m.: 0-50 pg/ml To diagnose Cushing's disease To differentiate primary and secondary adrenal insufficiency Primary adrenal insufficiency Cushing's disease Congenital adrenal hyperplasia Ectopic ACTH syndrome Primary adrenal hypersecretion Cushing's Syndrome Noncompliance with medication, diet, or activity restrictions Administration of radioactive material within 7 days Pregnancy Ingestion of Alcohol Amphetamines Calcium gluconate Corticosteroids Estrogen Lithium Spironolactone