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Nhs cortisol test

Nhs cortisol test

Hi all

I have got a big question that I really need an answer to. Around a months ago I gave a private saliva cortisol test, the results show a very low levels. Today I received my nhs cortisol test which according to my doctor shows a perfectly reasonable level.

Serum cortisol level

544nmol/l. 171.00-536.00nmol

My doctor says that salaiva test test is unreliable?

I have also done a pupil test at home which showed a deficiency in my adrenal test. Basically I would like to know if anyone can tell me what I need to do next?

Because am little confused?

I also attached my cortisol so you can understand better.

9 Replies

When you had the blood draw done was it just a straightforward blood test? Or was it more complicated than that? Also :

1) What time was the blood taken?

2) Had you eaten before it?

3) Had you drunk anything except water before it?

Cortisol testing in blood should be done as early as possible in the morning, while fasting. If you had eaten, or drunk anything except water, particularly if you had anything with caffeine in, it will have boosted your cortisol and made the result meaningless.

Regarding saliva testing for cortisol and some other hormones - NASA uses it to monitor their astronauts and the World Health Organisation approves of these tests too. I think the FDA in the USA is also happy to test cortisol in saliva.

1 like


Yes it was like a normal blood test.they specially order 4ml bottle to take cortisol test.

And no I didn't eat or drink any thing before test.

Still very confuse..


I suggest you should buy the book "Adrenal Fatigue, the 21st Century Stress Syndrome",

You will find many answers how you can recover from adrenal fatigue.


Thank you:)))



Cortisol levels can vary considerably even when tested at the same time on different days. As ever, blood tests are only ever good for that moment drawn.

I had a dangerously low cortisol level sometime ago but when I went for a short stathecen test (also known as reliable but nothing else offered to me) my levels has up'd to ok.

If I was you I would ask your gp to give you three or so tests to try and get an averaged out result.

I know how low levels make me feel (from my experience), you likely do too.

Wishing you well.



Ho thanks for your reply.then what did you do to heal your adrenals?

Because I don't really know what to do next.


This is interesting, as the exact same thing happened with me, and my blood cortisol level was almost exactly like yours. My saliva test also showed low levels. Very confusing!


I suffer from adrenal insufficiency and take hydrocortisone each day. I would suggest that the level of cortisol fluctuates but the real test to determine whether your adrenal gland is impaired is a short synacthen test. This will actually test whether your adrenal glands can rise in response to stimulation. The NHS don't recognise adrenal fatigue, but I think that is wrong because you will only fail a short synacthen test if your adrenals are 'asleep' or severely damaged. What it doesn't show is whether the adrenals are becoming damaged. Hope that makes some sense? X


What about testing for Secondary Adrenal Insufficiency. I'll bet that is more common than Addison' s.


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