advice on synacthen test

[ScriptMaz]

for anyone who has been following my story they will know I’ve been having medication issues and I am now taking T3 only. Still having issues with weight gain. Spoke to my endocrinologist last week and she has agreed the increase to 40mcg. This was after she had suggested trying a small dose of levothyroxine. I became hysterical at that point as I felt like my whole body was shutting down on that. She has now booked me in for a synacthen test but on the letter it said it’s to check if I have low cortisol. I checked the symptoms of that and I have none of them. Do they check for high levels too?

[greygoose]

Sounds like another doctor that has no idea what a synacthen test is for. It's not to find out if you have high or low cortisol, that should be tested before even thinking about a synacthen test. It's to find why someone with with low cortisol has low cortisol: is it an adrenal problem or a pituitary problem? But doctors don't seem to know that.

[ScriptMaz in reply to greygoose]

I googled high and low cortisol and I seem to have a few of the high symptoms and absolutely zero low ones. I told the endocrinologist that I was concerned about not losing the extra weight I put on since being diagnosed hypothyroid and she suggested a cortisol test. I thought it was to check for high but clearly not. I agree, I don’t think she knows what she’s doing

[greygoose in reply to ScriptMaz]

What you need to see if it's high is either an 8 am serum cortisol test, or a 24 hour saliva cortisol test. She can order the first one, if she's so inclined - it's quite a standard blood test. But for the saliva test you'd have to do it privately.

But, high or low cortisol, not being able to lose weight can be a hypo symptom. And 40 mcg T3 is not a high dose for someone on T3 mono-therapy. Could just be that it's not high enough for you.

[ScriptMaz in reply to greygoose]

Because of the advice on this forum I suggested to her that I’m under medicated and she increased it from 30 to 40. The only reason she agreed was because my gp had ordered a thyroid function test and my TSH was 15. I said that I am starting to feel better but the weight was bothering me and she said yeah you’ll probably never get the weight off

[greygoose in reply to ScriptMaz]

Stupid woman. TSH of 15? She's been undermedicating you for a long time, then. It takes a while for the TSH to get that high. And then she increased by 10 mcg in one go? Pft. You certainly won't get the weight of under her tender care.

[ScriptMaz in reply to greygoose]

I think I’ll be relying on this forum for information rather than my endocrinologist

[greygoose in reply to ScriptMaz]

I think that's a good idea.

[Jazzw]

Also keep in mind that 60mcg T3 is generally considered to be akin to a full replacement dose. 40mcg is probably not going to be enough.

Suspect your “endo” is little more than a diabetes specialist if they’re nervous about raising your dosage. Unfortunately very common.

[ScriptMaz in reply to Jazzw]

I actually told her that I thought 60mcg would be an optimal range for me and she said no, that’s very high

[Jazzw in reply to ScriptMaz]

She’s wrong. 😑

[humanbean]

If you want information on preparation, timing etc for the SST then this document is the one you need - it's called the Endocrine Bible.

See pages 68 - 70 :

imperialendo.co.uk/Bible202...

Another name for the test is the ACTH Stimulation Test :

en.wikipedia.org/wiki/ACTH_...

[ScriptMaz in reply to humanbean]

After reading that I still have no idea why she thinks I need this. I’ve never had my cortisol levels checked and going by the symptoms I read elsewhere there’s more chance I have high cortisol levels than low levels. I’m now concerned that if my levels are high and they’re pushing more in then I might get really ill from it

[humanbean in reply to ScriptMaz]

Personal anecdote... I was convinced I had low cortisol based on my symptoms before I ever had a test. When I did a 4-part saliva test it turned out my cortisol was substantially over the range for three of the four samples and high in range for the remaining test. I'm not alone in getting my own cortisol wrong. Another thing is that some of the symptoms of low cortisol can occur in high cortisol and vice versa which can lead to incorrect assumptions. I've never had an SST myself.

I would suggest just going through the test and using it as a learning experiment at somebody else's expense. If something goes terribly wrong then remember you'll be in a hospital where help will be available. Can you take a partner/friend/relative with you? And definitely take a book with you. Be as calm as possible throughout the test to reduce the risk of having cortisol which is higher than normal for you. Don't be late.

I can't remember anyone reporting on the forum having a dangerously bad experience of an SST. I think having extremely low cortisol can make the test more dangerous which is why the test is done in a hospital. For those with high cortisol the test will most likely not be a serious problem.

The SST involves being given tetracosactide which is an artificial form of ACTH. The natural form of ACTH is made by the pituitary.

To learn more about it :

bnf.nice.org.uk/drugs/tetra...

en.wikipedia.org/wiki/Adren...

One of the problems of the SST is caused by penny-pinching. In that link I gave you to the Endocrine Bible, on page 69 it says :

METHOD

1. 0900h: take 7 ml blood for cortisol (red or yellow top Vacutainer) and ACTH (purple top, on ice to

lab immediately).

2. Give 250 micrograms tetracosactride i.m. (ideally) or i.v.

3. 0930h: Take 3 ml blood for cortisol.

4. 1000h: Take 3 ml blood for cortisol.

To save money doctors will often not take blood to test ACTH. As a result they won't know your level of ACTH and won't be able to diagnose Secondary or Tertiary Adrenal Insufficiency in patients who have either of those.

The different types are described here :

en.wikipedia.org/wiki/Adren...

[ScriptMaz in reply to humanbean]

Thanks for the advice. I’m taking my sister with me. I feel a bit more relaxed about it after you explained it in more detail. Hopefully this will help get to the bottom of why I’m not losing any of this extra weight. If the test comes back normal then it’ll give me extra information to convince the endocrinologist to up my medication and get me to the correct level of T3

[Incoguto]

Christ, TSH 15? You are undermedicated.

[ScriptMaz in reply to Incoguto]

The endocrinologist put me up to 40mcg and I told her it’s a start. She said I’ll see you again in 5 months. I asked about increasing it steadily but all she said was we’ll look at the synacthen test first.