Individual test · Labcorp 500130

Corticosteroid-binding Globulin (CBG)

This test measures the level of corticosteroid-binding globulin (CBG), a protein that carries cortisol through your bloodstream. It helps show whether abnormal cortisol results are caused by a problem with your adrenal glands or simply by changes in how much protein is available to transport the hormone. This measurement helps rule out false impressions of cortisol excess or deficiency that might occur due to conditions like pregnancy or liver disease. However, this test does not measure cortisol itself and cannot diagnose specific adrenal disorders without additional hormone testing.