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Your doctor has recommended that you take this test to help with the diagnosis and management of your condition. Please read this carefully and ask us about anything that is not clear or if you would like more information.
The test checks your body’s ability to make a natural steroid hormone or chemical signal called cortisol. Cortisol is produced by the adrenal glands, which are just above the kidneys, in response to instructions from the pituitary gland, which is a small gland beneath the brain.
A problem with either of these glands can result in low cortisol levels. Cortisol has many vital roles in maintaining normal healthy functioning, and is a very important part of the response to ‘stress’ of any kind, including other illnesses.
The test will take about 45 minutes in total.
The test will be carried out by an endocrine specialist nurse or a general nurse.
You can eat and drink as normal before this test. If you take steroid hormone therapy (e.g. hydrocortisone or prednisolone) please do NOT take your morning dose before the test. This will enable us to see if you still need this treatment or not.
After the test you should CONTINUE to take your hydrocortisone or prednisolone as usual until the results are available. If you bring your tablets with you, you can take them after the blood samples have all been taken.
You will be given an injection of Synacthen, a natural ‘messenger’ hormone. This is normally produced by the pituitary gland and stimulates the production of cortisol by the adrenal glands.
We will take a sample of your blood sample to measure your cortisol level. We will then inject the Synacthen into a vein or into a muscle such as the buttock. Half an hour after this we will take another blood sample to see how your cortisol level responds to stimulation by Synacthen. After this you can go home.
This test has no common side-effects or after-effects.
There is no alternative to this test, which is a very safe way to assess your ability to make cortisol.
Your blood samples are sent to the laboratory for analysis. Either the endocrine specialist Nurse or your endocrinologist will discuss the results with you when they are available. If you have been taking hydrocortisone, we will be able to advise you about whether you need long-term hydrocortisone treatment or not.
Endocrine Specialist Nurses email@example.com
Princess Royal Hospital, Haywards Heath
Endocrine specialist nurse 01444 441881 Ext. 65660
If you have any urgent or emergency questions then your GP can advise you or they will contact the hospital on your behalf.
Patient self-help groups and further information:
This information is intended for patients receiving care in Brighton & Hove or Haywards Heath.
The information in this leaflet is for guidance purposes only and is in no way intended to replace professional clinical advice by a qualified practitioner.
Publication Date: July 2021
Review Date: April 2024