The DHEA-S (Dehydroepiandrosterone sulfate) test measures the level of DHEA-S, a hormone produced by the adrenal glands that plays a role in the production of other hormones like estrogen and testosterone. The test is performed by drawing a blood sample, which is then analyzed to determine the amount of DHEA-S in the bloodstream. It is commonly used to assess adrenal gland function and diagnose conditions such as adrenal tumors, polycystic ovary syndrome (PCOS), or adrenal insufficiency. The DHEA-S test is typically administered when a patient exhibits symptoms of abnormal hormone levels, such as excessive hair growth, infertility, irregular menstrual cycles in women, or signs of adrenal dysfunction. It may also be used to evaluate individuals with unexplained symptoms like fatigue or low libido, or to monitor certain endocrine conditions.