ACTH; ADRENOCORTICOTROPIC HORMONE, PLASMA

What this test checks

Measures ACTH, a hormone from the brain that signals adrenal glands to make cortisol. Used to find the cause of cortisol problems.

Why do people get this test?

Used in evaluating Cushing's syndrome (high cortisol) and Addison's disease (low cortisol).

When you should consider this test

• Suspected Cushing's or Addison's disease
• Unexplained weight gain or weight loss
• Specialist requested

How to prepare

Usually taken in the early morning. Stay calm and rested before the test.