Hello there, I am new to this site and am usually on the Pernicious Anaemia page but hope someone can give me advice please.
I have been taking Levothyroxine since the late 1990's and have kept on 125mcg per day and been fine until the last few months. I have always struggled to convert T4 to T3 and tended to have a lowish TSH. I wonder if the B12 injections might have improved my ability to convert T4 to T3? I am now over 65 years of age.
I was diagnosed with Pernicious Anaemia a year ago and also have vitamin B12 hydroxocobalamin injections regularly to treat it.
The racing pulse is happening regularly nowadays and I am a little confused because I have had this symptom with both too much and too little thyroxine medication in the past. The blood test results probably point to too much thyroxine I guess.
At the moment I am feeling more anxious than usual, having stomach upsets, hair loss, night time sweats, unable to sleep properly, and I am 20kg lower in weight than my maximum weight but remained on the same dose. It may well be obvious to you experts here but I am wondering about reducing my Levothyroxine dose. I tried to discuss with GP but got nowhere.
Latest blood test results: Serum TSH level 0.26 miu/L (reference range of 0.35 to 4.94),
Serum free T4 is 18.6pmol/L (reference of 9-19.1), Serum T3 is 3.5pmol/L (reference of 2.4-6)
I would be so very grateful for any comments and guidance.
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yorkshiregirl4
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A racing pulse is quite common with a low FT3 which yours is.
On B12 injections its also important to take care of other vitamins and minerals that work together with your B12. The same goes for your thyroid hormone. We need all key vitamins at OPTIMAL levels for thyroid hormone to work well.
What are your latest results for ferritin, folate & D3? Are you supplementing anything else other than B12?
How are you taking your thyroid blood tests? Recommended at 9am or earlier for highest TSH, last dose of Levo 24hrs before and fasting, only drinking water before the test.
You may need the addition of a small amount of T3 but vitamin levels are important for conversion so lets check those first.
Thank you for your informative response. I have been blown away by all responses and feel so much more confident that with your assistance my health issues can be resolved. Very grateful.
Having taken levothyroxine for so long with no apparent problems I have to admit a marked lack of knowledge. I was simply told that I do not convert T4 to T3 very well from the outset. I cannot believe that I even had 2 Endocrinology appointments in the last year with no advice. I now realise they were a complete waste of time. I have just checked my records to realise my previous T3 was in 2018 when it was 5pmol/L. I have been refused T3 blood tests since that date until February this year. In fact this test may not happen again at my GP's.
I have spent the last 18 months concentrating upon newly diagnosed issues of Pernicious Anaemia (with no idea how long I have had it), Bile acid malabsorption, atrophic gastritis, gluten sensitivities and gluten free for 3 years (not diagnosed Coeliac), and iron deficiency without anaemia.
In reply to your kind comments. I was taking various vitamins and minerals before my racing pulse episodes when I mistakenly believed they may be reacting adversely with the levothyroxine. I was taking folic acid, vitamin D3, vitamin C and gentle iron. My ferritin levels are now okay (over reference range) because I discovered decades of (unknown to me) iron deficiency and was able to have an iron infusion. The latest test results are serum folate are 15.2 ug/L (reference 3-20.5) on February 2024 and vitamin D on September 2023 is 95 nmol/L (reference 50-200)
For my latest thyroid blood tests I did have an early morning appointment but had drunk a cup of tea. I would be very grateful for advice regarding the best time to take levothyroxine, appropriate vitamins and minerals and when to take and about obtaining T3. I now realise that I have probably inadvertently wandered into bad practice over the years. I have tended to stop the levothyroxine during an episode of racing pulse which seems to bring about an improvement but realise this may be a coincidence.
Sorry for the lengthy ramble but many thanks in anticipation.
Unfortunately we cant rely on the NHS to do FT3 test and many in this group are forced to buy their own private blood tests to get the blood results they need to feel well.
If you are on B12 injections then its often recommended to take a B complex as well as B vitamins need each other to work properly, so definitely you need a B complex.
If you've had an iron infusion then you likely don;t need an iron supplement but will need to keep an eye on where your level is.
Your vit D in Sept 20203 was good but if you have stopped the supplement then its likely to have fallen back again so I would restart what you were taking making sure to add vit K2 if your supplement doesnt already have it. This helps the D3 go to your bones.
Levo is best taken on an empty stomach 1 hour before food or anything other than water to drink. You can also take it at bed time which works well for many.
You can be prescribed T3 on the NHS but it can be a postcode lottery dependent on how your local Endo/hospital view T3 therapy. Many get T3 on a private basis and it doesnt have to be expensive.
You can email info@thyroiduk.org for a list of T3 friendly Endo's. Then pick a couple and make a post asking for feedback on them by private message.
Your racing pulse is more likely to be due to your low FT3. Many people feel better when stopping Levo but it doesnt last long before the hypo symptoms creep in.
Thank you so much for your further information. I now feel confident to progress in a more appropriate way. I need to investigate a few resources that you have mentioned and decide what actions to take from now on. Thank you for your kindness.
I want to thank you for your suggestion to consider taking Levothyroxine at either am or pm. I had never thought of this nor heard anyone suggest this before. I admit to not thinking it would make much difference. How wrong was I? Within a short space of time of taking Levothyroxine at bed time my year long insomnia (sleeping just a few hours a night) and general mood has improved massively. Thank you to everyone who suggested bedtime taking of levothyroxine and also for all other helpful suggestions and private testing recommendations. Many thanks
Juggling PA treatment too, which I now understand can give palpitations as well as thyroxine levels. I am looking to getting full blood tests undertaken shortly with Blue Horizon and will then make decision about choosing appropriate doctor re. T3 if needed. Unfortunately local doctor on your list proved not very helpful when I happened to see him a year ago so may need to travel further. Thanks.
You have a high in range FT4 but very low FT3, its the low FT3 that gives you symptoms and even more confusingly sometimes it can be very hard to seperate low FT3 from over range FT3. You are what's known as a poor converter.
Your body isnt converting your Levo, synethetic FT4 into the active FT3. This can be due to poor vitamin and mineral levels, poor absorbtion by the gut, other medications or health conditions, peri menopause or other hormonal issues or down to genetics.
It sounds as though you would benefit from adding some T3 as even if you increase your Levo you will probably end up with a high or even over range FT4 which isnt desirable, but still have a woeful FT3. But as Jaydee rightly says you need to check your other nutrients first.
Hello Sparklingsunshine, many thanks for your reply. You are quite correct that increasing my levothyroxine simply pushes up my FT4 whilst the FT3 remains the same. I am also looking to address recommended vitamins and minerals but I am also wondering if T3 has to be prescribed after having an appropriate blood test, also is the levothyroxine reduced at the same time T3 is started?
Thorne Basic B recommended vitamin B complex that contains folate, but they are large capsules. (You can tip powder out if can’t swallow capsule) Thorne can be difficult to find at reasonable price, should be around £20-£25. iherb.com often have in stock. Or try ebay
IMPORTANT......If you are taking vitamin B complex, or any supplements containing biotin, remember to stop these 7 days before ALL BLOOD TESTS , as biotin can falsely affect test results
In week before blood test, when you stop vitamin B complex, you might want to consider taking a separate folate supplement (eg Jarrow methyl folate 400mcg) and continue separate B12
Post discussing how biotin can affect test results
Unfortunately I don't always have the same make of levothyroxine. I have never had thyroid antibody test but low iron levels resolved for the time being by iron infusion. My Coeliac test came back negative but I am better gluten free and have been for a few years now. Thanks for mentioning the B complex, which I have not been taking but will be doing so now and I hadn't appreciated there was a difference between folic acid and folate. Starting back on vitamin D. I will read your other links and am so very grateful for your thorough and helpful reply. Thank you.
Strongly recommend getting FULL thyroid and vitamin testing once a year
If you notice difference between brands of levothyroxine always get brand that suits you best
Recommended that all thyroid blood tests early morning, ideally just before 9am, only drink water between waking and test and last dose levothyroxine 24 hours before test
This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)
Private tests are available as NHS currently rarely tests Ft3 or all relevant vitamins
Testing options and includes money off codes for private testing
Personally, as there are margins of errors in the blood tests, I think two tests are needed before making a decision on increasing or decreasing. And, if possible, looking at your historical numbers alongside considering symptoms and making an educated guess on where your wellness lies.
With that said, your TSH is below range, FT4 just within, and FT3 is on the low end. You could lower levothyroxine to see if that helps kick start FT3 production, or just feel better as I have found I feel worse the higher my FT4 goes on levothyroxine only.
Other options include T3 or NDT usage.
Or, your issues could be due to something else entirely.
That's all very interesting. I have had these sort of results for a long time but no professional has offered any helpful advice or recommendations. I am so pleased that I posted my question on this forum and have been blown away by the volume of suggestions and helpful information. I do have a question though, what is NDT please? Many thanks for your assistance.
I would suggest that low iron and/or low ferritin could be one factor in your symptoms. Have you had any iron/ferritin testing in recent months? If not it might be worth asking your doctor to give you a test.
Low iron is very common in thyroid disease. I think it is also true that people with B12 deficiency often have low iron too.
Do you ever get your folate tested? If not I think it would be worth doing.
Many thanks for your reply. I was iron deficient for years but have had an iron infusion not long ago. Folate tested not long ago too but thanks for your reply. It just goes to show how many possibilities there are for these sort of problems.
Many thanks for your advice and I will certainly keep an eye on my iron levels. I will investigate further re. options rather than iron infusion. Many thanks.
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