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Thyroid UK
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High Cortisol Result - any advice would be gratefully received !

Hi - seeing a Fantastic Endo in Brighton ... He has just put me on a combined therapy of 125 levo and 12.5 mg of T3 twice a day ( so 25mg a day in total )...

I was on 150 levo before but my results were not improving - so my first question is what is 25mg of T3 equivalent to ?

Secondly my Cortisol result was high at 549 ( range 166 - 507 morning range ) - my concern is that I have horrific insomnia and large weight gain around the tummy - this level of cortisol cant be helping at all ... he hasn't suggested anything to do with the cortisol yet and I wondered what questions I should be asking and what is the treatment for high cortisol ?

Many thanks for any help you can offer

8 Replies


25mcg T3 is equivalent to 75mcg T4.

I can't help re high cortisol.

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This is an excerpt:

Equivalencies of Thyroid Preparations Based on Clinical Response

Thyroid Agent Approximate Equivalent Dosage

Levothyroxine sodium - 100 mcg or less

Liothyronine sodium - 25 mcg

Liotrix (levothyroxine sodium/liothyronine sodium) 50 mcg/12.5 mcg (Thyrolar)

Thyroglobulin 65 mg

Thyroid 60–65 mg (1 grain)

When switching from another thyroid preparation to liothyronine, discontinue the other preparation, then initiate liothyronine therapy at a low dosage and titrate as needed in small increments after the residual effects of the previous thyroid preparation have subsided. a c

When switching from liothyronine to another thyroid preparation, consider the rapid onset and dissipation of effects of liothyronine and, to avoid relapse, start therapy with the replacement thyroid preparation several days before complete withdrawal of liothyronine. a b




Was that an early morning blood cortisol test? Not very helpful. You need to know what it's doing for the rest of the day. And the only way to do that is to do a 24 hour saliva cortisol test. But, you won't get that on the NHS. You'll need to do it privately.

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it was first thing - I am seeing a private endo so I can ask for that ..

thank you


You're welcome. But don't be surprised if he doesn't know what you're talking about, or fobs you off!


The normal range for cortisol first thing in the morning should be between 300-600 depending on the reference range used by the laboratory testing it. You also say that you are are struggling with insomnia & weight gain especially around your tummy? Do you have any other symptoms such as acne, muscle weakness, anxiety, a round face? If so you could look at Cushing's which is a condition as a result of high cortisol levels. It can be caused by a benign tumour in either your pituitary gland, which can affect your thyroid results. or a benign tumour in your adrenal glands. Other causes can be long term use of steroids. Have a look at the Pituitary foundation website pituitary.org.uk for some info on Cushing's. If you are are on Facebook there is a Cushing's UK group which may help. Be careful of seeing a private Endo a many of them don't know enough about Cushing's telling you that it is a rare condition that you couldn't possibly have! You may need to see an Endo who is conversant with Cushing's. Hopefully it won't be but feel free to ask me more questions as I have had Cushing's. x

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Thank you - sorry for delay - I've been away !

I have muscle weakness/ tingling in my legs but my GP thinks that is more to do with the Menopause ( I'm 53 ) .... I know I don't have a Pituitary tumour as I had an MRI scan recently and all was clear ( I had the scan as I have secondary Hypo and he wanted to eliminate a tumour as the cause ) ..... I guess my frustration is that until I can sleep I wont know if the new T4 & T3 therapy is working because I'm still tired !!

Thanks for your help - and happy new year


Do you have good B12 levels ?


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