Thyroid UK
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Dexamethasone Reactions?

Hi all,

I was wondering if anyone had any experience of having done the Dexamethasone suppression test? 

I've got a it arranged for next week but I'm slightly nervous about having it done. This is really down to the fact that so far I haven't had an actual diagnosis and no doctors know what's wrong with me. Multiple endo's have said I have all the symptoms of adrenal insufficiency but my cortisol blood tests are always high and I passed the Synacthen test. I'm a bit worried that if I did have low cortisol then taking the Dexamethasone might lower it even further and make me more ill. 

I was hoping someone might have had some experience of it? And if so did you have any sort of negative reaction to it? And does anyone know if you're supposed to avoid having it done if you have any thyroid issues? 


3 Replies

They tested me for Cushings even though I had no symptoms. The suppression test itself was no problem, but it suppressed my cortisol to 20, with the result that I was rather wobbly for a couple if days until it rose again.

Needless to say, I do not have Cushing's, this was just another red herring.


Thanks for getting back to me!

I'm sceptical I have Cushing's too, but I feel like I've got to have the test just to rule it out and move onto the next thing.

When you say wobbly for a few days, how bad were you? Was it really noticeably worse or more of a minor effect?


As it happens I was on a research project at the time which involved my being on an exercise bike for half an hour at a time.  My performance was noticeably poorer on the day of the test.  I was noticeably wobbly, but I was still at work.  I could feel it, I guessed what it was and I worked through it.  I wouldn't worry about it.


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