Short synacthen test: I had this done yesterday... - Thyroid UK

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Short synacthen test


I had this done yesterday and felt horrible the moment they put it in the cannula, I went immediately dizzy and nauseous, I got home afterwards and slept the rest of the afternoon away and again today just completely fatigued - anybody else suffered after effects?

I am grateful for finally being checked properly from all angles but blimey that was unexpected!!


10 Replies

I'm glad you mentioned that because I'm scheduled to have it done soon and as much as to be poked and probed for my own health satisfaction I'm a bit apprehensive about this test.

So side effects for you were exhaustion only or was there some more? We're you able to drive yourself home after the procedure? Also was it painful?

WobblyX in reply to trelemorele

I had this a couple of months back and no reactions at all. I did have husband to drive me home as I had heard mixed reports and was a bit nervous but was absolutely fine for me...

No more painful than a blood test - I felt dizzy and sick all of yesterday and ate like a horse as I felt like I had low blood sugar, the fatigue hit about lunchtime and has stayed. I drove myself though in hindsight having someone drive me may have been more sensible!!

I just wondered if anyone else had felt like it and whether it was an indication of the results?!

I went the opposite way. That night I was happy hyper & pain free for almost 2 days (first time in 2 & a half years of not being in pain!!!).

If they could make me feel like that all the time, I would be over the moon!


I think they pump you with acth to induce cortisol production.

If artificially increasing both hormones made you feel that great maybe you're deficient then?

Yep. Although the results came back normal & the endo said that if all else fails then he might consider a low dose steroid treatment, but it would be hard to justify right now. Annoyingly they did the test in the afternoon & apparently it should be done at 9am or the results are invalid. Endo ignored this when I brought it up!

My private saliva tests were low, except the afternoon one that spiked high.

PaulineS in reply to Rainbownut

Did you get the results for the test? Often Endo's will say you have passed if the result doubles but ignore a low baseline cortisol. So if you have a low base level cortisol but double it, it only shows that you don't have primary adrenal insufficiency/Addisons but you may still have secondary adrenal insufficiency.

Ooh thanks for letting me know 're test timing. Will take it up with my team if they book me for afternoon test then.

My saliva cortisol tests are bottom low all day long. Similar to yours then with one difference. Hopefully I'll have similar to yours side effects then.


Summer64 in reply to trelemorele

I was told it had to be done at exactly 9.00 am. To feel a bit faint they say is normal and expected which is why they like you on a bed. I only felt that very briefly while they injected the stuff in but nothing lasting.

I suddenly started crying during mine and couldn't stop - really weird feeling. But afterwards I felt fantastic. Test was abnormal. Referred for CT scan and insulin stress test (really, really nasty and not recommended)

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