1. Do I need both tests (blood and urine), or is one better than the other?
If your doctor suspects Cushing's syndrome, both blood and urine may be tested. Blood cortisol is easier to collect but may be affected more by stress than the urine test.
2. How do I tell if a high cortisol level isn’t just from stress?
There are several approaches that your doctor can take. The simplest involves repeating tests at a time when you feel less stressed. Your doctor can also use a dexamethasone suppression test to see if this decreases your cortisol level. Multiple tests are often needed to tell if stress or disease is causing a high cortisol level.
