Private Cortisol Test
Cortisol is a hormone produced by your adrenal glands that helps regulate several important functions in the body. When cortisol levels may be unusually high or low, a cortisol blood test can help with the investigation. At My Private Clinic, testing is arranged following a consultation with Dr Faizal Secretary.
GP-led · Morning cortisol testing · Results usually within 72 hours
What is a cortisol test?
Cortisol is made by the adrenal glands, which sit just above the kidneys. It is often called the stress hormone, but it does much more than help us deal with stress. It also helps the body control things like blood sugar and blood pressure, supports metabolism, and plays a role in how the body responds to illness or injury.
A cortisol blood test measures how much cortisol is in your blood at that moment. The time of day matters, because cortisol levels change throughout the day.
Reviewed by Dr Faizal Secretary, MRCGP · GMC 7606534
Why might you need a cortisol test?
Dr Faizal might suggest a cortisol test if your symptoms indicate that your cortisol levels could be too high or too low. High cortisol can be a sign of conditions like Cushing's syndrome, while too little cortisol can be linked to adrenal insufficiency, which includes Addison's disease.
Signs such as feeling tired, changes in weight, low blood pressure, and changes in the skin can have many different causes, so a cortisol test is just one piece of the puzzle. Dr Faizal looks at your symptoms and health history to decide whether testing makes sense.
What does a cortisol test measure, and why the morning?
A serum cortisol test shows how much cortisol is in your blood when the sample is taken, helping to indicate whether your levels are too high or too low. When reviewing your results, Dr Faizal considers the time of day, your symptoms, your medical history, and any medicines you take. Sometimes an ACTH test or other tests may be needed.
Cortisol does not stay at the same level all day. It usually follows a pattern, with levels higher in the morning and slowly falling as the day continues. This is why a morning cortisol test, often around 9am, is commonly used when checking how well the adrenal glands are working. Dr Faizal will advise you on the exact timing when your appointment is arranged.
How is a cortisol blood test done?
A cortisol blood test is a straightforward blood test. When you arrive at the clinic, you have a chance to talk about the test and any concerns before the sample is taken. A doctor or nurse takes a small amount of blood from a vein in your arm with a needle, which usually takes a few minutes. You might feel a brief pinch when the needle goes in.
The sample is then sent to a laboratory for analysis. Your result is considered alongside the time the sample was taken, your symptoms, and relevant medical history.
How should I prepare for a cortisol blood test?
To get ready for a blood test, it helps to know why you are having it and what kind of sample is needed. Dr Faizal will give you instructions before your appointment.
Do you need to skip breakfast?
Not all cortisol blood tests require fasting, so do not skip breakfast unless you are told to. If fasting is needed, the clinic will let you know before your appointment.
What about your medicines?
Some medicines, such as steroids, can change your levels or affect the results. Tell Dr Faizal about all the medicines, supplements, and treatments you take, and do not stop any unless advised to.
Does exercise change the results?
Cortisol levels rise when you are stressed or have exercised, which is why Dr Faizal considers what was happening when the sample was taken when reviewing your results.
If you are not sure what to do before the test, it is better to contact My Private Clinic than to guess. We will tell you what you need to do for your blood test.
What happens after your cortisol test?
Your blood sample is sent to a laboratory for analysis, and the result shows the amount of cortisol in your blood at the time the sample was taken. Your result is not interpreted on its own. Dr Faizal considers the time of day, your symptoms, medical history, and any medicines you take, and the laboratory provides a reference range to help with interpretation.
A result outside this range does not necessarily mean you have a health condition, and a result within the expected range may not explain all of your symptoms. If your result needs further investigation, Dr Faizal explains what this means and advises on the next step, which may include further blood tests or a referral to a specialist, depending on your circumstances.
How can Dr Faizal help you?
Before arranging a test, Dr Faizal talks to you about your symptoms, your health history, and any medicines or supplements that could change the result. This conversation helps him decide whether a cortisol blood test is really needed and whether anything else should be checked. He explains what the result means rather than simply handing over a number for you to work out on your own.
Every cortisol test is arranged after a GP consultation to make sure it is appropriate for your symptoms and medical history.
Why choose My Private Clinic?
When you arrange a cortisol test at My Private Clinic, the focus is not just on taking the blood sample. It is on making sure you understand why the test is being done and what happens afterwards. The service is available at our clinic in Fulwood, and results are usually available within 72 hours.
GP-Led Care
Cortisol testing is arranged following an appropriate clinical assessment.
Clear Explanations
Results are considered alongside your symptoms and medical history, and explained clearly.
Continuity of Care
If further investigation or referral is needed, Dr Faizal guides you through the next steps.
Meet Dr Faizal
Dr Faizal Secretary is an experienced NHS GP and founder of My Private Clinic in Preston. His approach is centred on listening carefully, explaining medical information clearly, and helping patients understand what happens next.
"Good healthcare starts with listening properly."
Dr Faizal Secretary, MBChB MRCGP · Read the full clinical profile →
Cortisol test price
The cortisol test price is available on application. Please contact My Private Clinic for the current cost and to arrange an appointment. If you are not sure whether a cortisol test is right for you and your symptoms, you can talk to Dr Faizal about it first. All costs are discussed before any test is arranged.
Frequently asked questions
What is a cortisol blood test?
A cortisol blood test measures the amount of cortisol in your blood at a particular time. It may be used when a doctor is investigating unusually high or low cortisol levels.
Why is cortisol tested in the morning?
Cortisol naturally changes throughout the day and is usually higher in the morning. This is why a morning cortisol test, often around 9am, may be recommended when assessing adrenal function.
Do I need to fast before a cortisol test?
Preparation can vary depending on the reason for the test. You will be given instructions before your appointment if any preparation, including fasting, is needed.
How long do cortisol test results take?
Cortisol test results are usually available within 72 hours. Your result is considered alongside the time your blood was taken, your symptoms, and other relevant medical information.
Can a cortisol test diagnose adrenal problems?
A cortisol test can provide useful information when investigating conditions such as adrenal insufficiency or Cushing’s syndrome, but it does not usually confirm a diagnosis on its own. Further testing may sometimes be needed.
Related tests & services
Arrange a private cortisol test in Preston
If you have been advised to have your cortisol levels checked, or you are concerned about symptoms that may need further investigation, Dr Faizal can help you decide whether a cortisol test is appropriate. Book a consultation at My Private Clinic in Fulwood, Preston.