I have been on thyroxine for decades so lots of blood tests - but I've been told to take it prior to a TFT blood test tomorrow. I have NEVER been told this before! Please can I get some advice - take, not take, it doesn't matter, ideally with explanation given.
Should I be worried by high TSH?
The reason for the blood test is my TSH is 25 (not below 4.2). T4 was 15.6 (range 12-22). I was on 75mcg and 100mcg alternate days, but advised to increase to 100mcg daily for 6 weeks prior to this blood test. I don't know reasons for this result. Should I be concerned or asking for different tests or the TFT will cover it?
Thanks
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Choc2222
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This sounds like theres a few things going on. You may be under replaced. You may be having absorption issues also.
For the blood test, do not take Levo directly before the test. If you do that you will be measuring what you have just taken and not the stable blood level.
Allow 24hrs from last dose Levo to the blood test. Fast before the test, only drinking water, stop any biotin supplement (b complex) 4-7 days before the test. Take Levo day of test AFTER the test.
How do you take your Levo? Its an extremely fussy hormone and wont absorb & work well of taken with anything else or anything close to it.
Always take Levo on an empty stomach an hour away from food or caffeine containing drinks & other meds. Many people find taking it at bedtime works well for them.
Thanks for the speedy reply! I thought taking thyroxine might skew the results. It will be 22-23hrs now before test tomorrow and I can skip multivitamin for today - thanks wasn't aware of this, so will definitely do for future tests.
I was advised to leave 30mins (not consistently stuck to!) before breakfast so bedtime might be more preferable for me, but I do like to snack! How long after eating is the stomach empty? I take antidepressant, sertraline at night, so I could leave an hour after thyroxine between the two. I was under the impression that the thyroxine helped my body's processes get going in the morning, am I right? Will it work as effectively if taken at night?
It presumably contains biotin as well, anything with biotin in should be stopped 3-5 days before any blood test as biotin can falsely affect test results
We always advise testing vitamin D, folate, B12 and ferritin and only supplement what’s necessary
Levothyroxine is an extremely fussy hormone and should always be taken on an empty stomach and then nothing apart from water for at least an hour after
Many people take Levothyroxine soon after waking, but it may be more convenient and perhaps more effective taken at bedtime or in middle of night if you reliably get up for the loo every night
Or set alarm for early morning, take Levo then and go back to sleep
No other medication or supplements at same as Levothyroxine, leave at least 2 hour gap.
Some like iron, calcium, magnesium, HRT, omeprazole or vitamin D should be four hours away
(Time gap doesn't apply to Vitamin D mouth spray)
If you were to start taking levothyroxine at bedtime/in night ...then adjust timings as follows prior to blood test
If testing Monday morning, delay Saturday evening dose levothyroxine until Sunday morning. Delay Sunday evening dose levothyroxine until after blood test on Monday morning. Take Monday evening dose levothyroxine as per normal
Bedtime Levo will almost certainly help your TSH. Take sertraline at 8 or 9pm.
Suggest you test key vitamins ferritin, folate, B12 & D3, start new post once you have the results. Multivitamin wont be helping as contains iron & iodine.
As TSH should always be under 2, with most members here reporting they feel best with this is closer to 1, an elevated reading shows that your thyroid is struggling and you require additional thyroid medication. It’s sensible to increase slowly- ie from 75mcg Levo to 75/100 alternate days (ie 87.5mcg daily), then to 100mcg daily, but likely you will need to continue increasing further to get TSH under 2.
What symptoms are you currently experiencing?
A member- to- member tip re blood draw is to get the earliest possible test (prior to 9am) and take daily dose of Levo after the blood draw (as TSH at highest level early morning).
Have you had FT3 tested at all?
Have you ever had thyroid antibodies checked to see if your condition is auto immune (aka Hashimotos)?
Have you tested key thyroid vitamins recently (folate, ferritin, B12 and vit D)? Having these optimal supports thyroid health.
If your GP is unable to complete all the above you could look to do this privately, as many forum members do, for a better picture of your thyroid health:
The blood clinic opens at 8am so I will get there early.
Every time that I have asked at doctors for FT3 to be tested, I am told that only TSH and T4 are tested, so maybe I will need to go private.
I have never had antibodies tested - is this something that you can ask a GP for or more private?
The last blood looked at FEPR/iron and I was told I'm not anaemic, and I have had previous involvement with Endocrinology who advised to take 800IU Vit D which I still do. Not B vits though.
Amongst other symptoms, I have unremitting tiredness - I asked if long covid/ME. Firstly prescribed and increased HRT, not worked. Advance Nurse Practitioner contacted endocrinology again and they didn't want to see me but said that a diagnosis of fibromyalgia could be made in primary care, so I was told that was it, nothing could be done in Sept 24. I don't think I fit this diagnosis at all. My calf muscle was sore at the time of the visit, which actually escalated to a back prolapse, but I do not routinely have aches and pain in body. I personally feel that a GP should have been involved to diagnose me. Endocrinology were involved in the past in testing my adrenal glands/cortisol as I thought I maybe had adrenal fatigue. Do these type of tests get done once and repeated after a certain length of time?
With accompanying brain fog, it is hard to get motivated and informed enough to challenge things. I am really glad I've come across this site though as it is really helpful!
Many of your symptoms may be linked to thyroid medication and key vitamins not being optimal. SlowDragon ’s posts are really useful on optimising vitamins.
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