Cortisol (Stress Hormone) Blood Test

What is a Cortisol (Stress Hormone) Blood Test?

Cortisol is a vital hormone produced by your adrenal glands that helps control your response to stress, regulate your metabolism, blood pressure, immune system, and maintain energy levels throughout the day. The cortisol blood test measures the amount of this hormone in your blood to assess if your levels are within a healthy range.

What does the test involve?

• Measurement of cortisol levels in your blood—performed via a finger prick test.

• Less commonly, cortisol may also be measured in saliva or urine for a full picture.

Why is the Test Important?

Cortisol plays a crucial role in your health—helping your body respond to stress, maintain normal blood pressure, support the immune system, and regulate blood sugar and metabolism. Testing your cortisol levels can help:

• Diagnose issues such as adrenal insufficiency (Addison’s disease) or excess cortisol (Cushing’s syndrome).

• Identify causes of persistent fatigue, unexplained weight changes, blood pressure problems, or mood swings.

• Guide treatment for ongoing stress-related health problems.

What Symptoms Might Suggest You Need This Test?

Consider a cortisol blood test if you experience:

• Ongoing fatigue, weakness, or low energy

• Unexplained weight loss or gain

• High or low blood pressure

• Mood changes—anxiety, depression, or irritability

• Changes in skin (such as easy bruising or stretch marks)

• Poor immune function or frequent infections

What Happens During the Test?

No special preparation is usually necessary, but you may need to avoid vigorous exercise or certain medications beforehand (please inform our clinical team about your routine).

• Sample Collection: A small blood sample is taken using a finger prick blood test. The process is quick and causes only brief discomfort.

• Analysis: Your sample is analysed to determine your current cortisol level. B

For some cases, further tests (such as the ACTH stimulation or suppression test) may be suggested by your GP to assess how your body produces and regulates cortisol.