Cortisol, Serum (8 AM)

Why This Test Matters

Cortisol is a hormone produced by your adrenal glands, which sit on top of your kidneys. It plays a key role in how your body responds to stress, regulates metabolism, and supports immune function. Measuring cortisol at 8 AM helps doctors evaluate whether your body is producing enough cortisol or if there’s an imbalance.

What to Expect Before the Test

No special preparation is needed for this test. You’ll have a small needle inserted into your arm to draw a blood sample. It usually takes a few minutes. If you’re taking medications that affect cortisol levels, let your healthcare provider know before the test.

What the Results Mean

Results help determine if your cortisol levels are too high or too low. Low cortisol levels (adrenal insufficiency) may cause fatigue, dizziness, or low blood pressure. High cortisol levels (Cushing’s syndrome) might lead to weight gain, high blood pressure, or muscle weakness. Your doctor will interpret the results in the context of your overall health.

Common Conditions This Test Helps Diagnose

This test is often used to diagnose conditions like Addison’s disease (adrenal insufficiency), Cushing’s syndrome (excess cortisol), or to check for problems with the pituitary gland, which controls cortisol production.