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Adrenal tests again (sorry!)

Sorry to go back to this but just wanting to get everything straight in my mind before my next appt.

Have just re-read some of the posts which is helpful but just need info all in one place IYSWIM :)

Right-here goes.....

1. Do you need to have the early morning cortisol test before you go onto the synacthin test?

2. Do you need to be off pred for both tests and if so how long before the test?

3. I think I've read rightly there is a pred substitute (so to speak) that you go on instead to keep asthma from going bonkers-what is it/how does that process work?

4. Do you have to go to hospital for the early morning cortisol test or can that be done by your GP if they open early enough?

5. I know you need to go into hospital for the synacthin test-what is the difference/benefits of the long/short test?

6. Are there any side effects from the injection you get?

Well, think thats it for now and many thanks to anyone that is still reading and got to the end of my posts!!

Thanks x

4 Replies

My last synachten test was some time ago, so I may have misremembered details...

For the short test, I turned up relatively early at the hospital. They placed a cannula, and used that to take an early cortisol reading. They then injected the synacthen, which I seem to remember caused a fluttery feeling in my tummy. They then took blood every half hour, for two (maybe 3) hours, from the cannula, to measure the amount of cortisol in my blood, and what increase the synacthen had induced.

I didn't come off prednisolone as it wasn't considered safe, so I can't quite remember how we got round that! I think it was by using a very specialised laboratory that can separate out the various steroids in your body, those that you have injested and those that you have produced. I think some patients switch to hydrocortisone.

I'm not sure I've done a long synacthen test, but I have done a day curve, to ensure that the dose of replacement steroids I was taking was sufficient to cover my needs, once they'd established from the short curve that my adrenal glands were not functioning at all. I think it was just as above, but with no synacthen, and an overnight stay in hospital so that they could take blood samples every couple of hours throughout the day and probably the night as well, to measure the levels at all times. This enabled them to plot how my levels behaved over the course of the day, and also whether my replacement dose was a) sufficient, and b) well timed,

Sorry not to remember more clearly!


This is MY experience

1. The short synacthin test takes a sample before, so i would guess thats the same as having an early morning cortisol test, i did not have a seperate early morning cortisol test before my short synacthin test. (as far as my understanding goes a level of over 200 excludes a diagnosis of adrenal insufficiency, for the pre-synacthin result, but if the level is lower but still goes up sufficiencly your adrenal glands may still be working)

2&3.I was told i had to be off pred for at least three days to do the test. To do this i stopped straight from 40mg of pred to 20mg of hydrocortisone (equivalent to about 5mg of pred) but this doesnt really help asthma an awful lot, its more to stop you going into adrenal crisis waiting for the test i think. I had two attempts at stopping pred before i managed to keep out of hospital long enough not to have pred upped again. Although like C i have found my asthma has been a bit better controlled since i had my adrenal insufficieny properly managed.

5.I believe that it is more common to do short synacthin first. This takes half an hour. I didnt have to be cannulated (yay) i just had a blood test, then they injected synacthin in your bum (i had no side effects at all, it just feels a tiny bit stingy as it is cold as it comes out of the fridge. then they waited half an hour (i think with 10 min obs and lots of people chacking i wasnt at all wheezy) and then they took another blood test and then i took my hydrocortisone and left.

I got the results the next day, so nice and quick!


Quick one, I'm following your threads with much interest as we are slightly behind you with Thomas's tests. I still don't have his results and feel anxious about his endo appointment next month. His asthma (touch wood) seems to have finally stabilised.

Have they taken your blood pressure lying down then standing up? When diagnosing my sister they did this in A&E a number of times.


Thanks for the input folks!!

I am really determined to get this sorted as the are they are they not functioning dilemma is really doing my head in!!

Hope it is good news but if not at least I can get my meds sorted and then GP, medics and myself know how to treat me when I'm suffering from other illnesses etc.

Fingers crossed x


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