I just had a telephone consultation with an NHS endocrinologist after being referred upon diagnosis (Sept 2020) and to be honest he didn't inspire massive amounts of confidence but that's not really the point of the post so I won't go into it. Basically he's booking me in to go to the hospital to do blood tests where they will test for underlying causes such as antibodies and test my adrenal glands.
Last week was 6 weeks since my last Levothyroxine increase so I was due to have blood taken at the GP. Endo said to not bother, because he doesn't want my medication adjusting before he does these tests as I need to be on a stable dose for at least a few weeks - otherwise it will skew the results.
He said it could be a few weeks until I get an appointment for these tests (and could be longer realistically).
What I want to know is - is it true that a recent dose change will affect the results of these tests?
If not I would rather follow up with my GP as arranged. I've not reached a stable dose yet and still very symptomatic so don't want to wait and waste time if it makes no difference. Also the GP had finally agreed to test my T3 level which I was looking forward to 😂
Thanks in advance
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stevensnj2020
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Because the body takes time to adjust and adapt to hormone changes it is usually recommended to leave 8 weeks between any change and a blood test.Please also be aware that even though the GP has said he would do ft3 blood test, it is often reported on here that the testing laboratory does not carry out the test as the TSH and ft4 are in range.
When on levo if you want to look at conversion of T4 to T3 you need to be on a stable dose of levo that has your TSH around 1.
Ah okay, thanks for the reply - I will try to hold off then.
To be honest my GP has said about testing ft3 before and it hasn't been done so I wasn't entirely hopeful, and maybe that's what's happened in the past?
Does that mean that if I were to order private blood tests there would be no point if TSH is still high and the ft3 value won't mean anything?
You can test ft3 if you just want to see the level but for comparison with ft4 to look at possible conversion issues TSH needs to be around 1 as this indicates that you are on a high enough dose of levo .
It depends what exactly the endo is testing for. Having an increase in dose won't affect antibody or adrenal testing. And, I can't see what else he could test for that would show under-lying causes.
But, if he's testing TSH, FT4, FT3, then an increase in dose would affect the results, yes.
Then again, it depends how long you're going to have to wait for an appointment to get these tests done. If it's going to be over six weeks, then you might as well go ahead and get an increase from your GP. Perhaps you should ring the hospital and see what they say about waiting lists.
No I don't know either, he was a bit cagey about what he was actually testing for and only explained the adrenal test. That's a good idea about ringing the hospital - he said 'a few weeks' several times but in my experience that can mean 4 weeks or 4 months...
I might also add that the impression I got from him is that he wants my GP to continue to manage things, and he made a comment about FT3 not being relevant which hardly inspires confidence 🤦🏻♀️
Hmmm... yes, not very inspiring. There's no reason why he shouldn't tell you exactly what he's testing for. But, the problem is, doctors think all patients are idiots and couldn't possibly understand blood tests because they haven't been to med school! If only they knew that we often understand better than they do! lol
You could get FULL thyroid and vitamins tested privately
How much levothyroxine are you currently taking
Do you always get same brand levothyroxine
All thyroid tests should be done as early as possible in morning before eating or drinking anything other than water and last dose levothyroxine 24 hours before test
Likely to need to improve low vitamin levels
What vitamin supplements are you currently taking
For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested. Also EXTREMELY important to test vitamin D, folate, ferritin and B12 at least annually
Low vitamin levels are extremely common, especially if you have autoimmune thyroid disease (Hashimoto's) diagnosed by raised Thyroid antibodies
Ask GP to test vitamin levels
Private tests are available as NHS currently rarely tests Ft3 or thyroid antibodies or all relevant vitamins
Currently taking 200mcg daily, dose was increased to this on 3/3/21.
Was taking Teva but requested Mercury Pharma instead and have been taking this exclusively for 3 weeks. Seems to have stopped some horrible symptoms I was getting like restlessness, dizziness and heart flutters, so going to make sure I keep getting this brand.
GP tested Vitamin levels, results from 24/3:
Vit D - 54 nmol/L ( Normal 50 - 174)
Serum B12 - 535 (180-995)
Ferritin 212 ug/L (13 -150)
Folate - 18.7 ug/L (Normal range N/A)
*Was previously blood transfusion dependent which has caused the high ferritin
Before these results was supplementing Vit D 800iu, have now purchased the Vit D spray you have recommended and supplementing 4000iu a day and 1200ug B12 spray.
Doubt the GP will test again so plan to re-test privately after several months and see if levels have improved.
Hopefully the endocrinology dept are testing for the relevant antibodies when I see them but will order private test if not. GP has also said he will test FT3 but if this doesn't happen then I will definitely be ordering this privately.
Seems like I'm on quite a high dose and not feeling the great improvement I thought I would, so want to make sure nothing is being missed!
he was a bit cagey about what he was actually testing for and only explained the adrenal test
Can you remember whether he named the adrenal test?
GPs will test cortisol (produced by the adrenal glands) using a simple blood test.
But endos in hospitals will sometimes do a test called the Short Synacthen Test (SST) which has a little bit more to it. For info on the SST read pages 68 - 70 in this document known as the "Endocrine Bible" :
Note that timing is important - the testing should be done as close to 9am as possible. Also note that a properly performed test should include a test of ACTH as well as cortisol, but endos rarely include the ACTH test, which I think is negligent.
If people have very low cortisol showing up in the SST then it suggests that the adrenal glands have failed and the patient possibly has Addison's Disease. But sometimes cortisol is fine and the ACTH level is low. A low level of ACTH suggests that either the pituitary or the hypothalamus has problems.
These various problems are called Adrenal Insufficiency, and there are three different types :
Thanks for this info, I will read over this as it's something I know pretty much nothing about.
No he didn't name the test, but said it would involve taking bloods, injecting me with something, taking bloods again after half an hour, then again after an hour I think? I think I have that right, it's a bit foggy!
Thanks for posting, I think this happened to me. I had a 45min drive to hospital for the blood draw, they talked about an ice pack. When results came back they had only done the cortisol and because that was in range they didn't do the rest of the test. Total waste of my time and half day off work. Plus as you say I could still have a pituitary or hypothalamus problem.
I read later that the SST is not a sensitive enough measure for thyroid /adrenal related issues, and more suitable to confirmation of Addison's Disease.
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Endo said no follow up see GP in a year - this was private visit a month ago!!!!!
Follow up from TSH at 37
Breathlessness follow up 
Gp rationale to not treat following my letter of complaint 
Second GP visit following private Thyroid Panel
