I posted last week about this and have since had an echo which shows normal heart function just very slow. 40-41 bpm and no issues from ASD repair I had as a child. This was fantastic news! I’m waiting on referral for a holter ecg and to see cardiologist. But the sonographer did say they’ll look at medication. Etc. obviously the thyroid impacts the heart and I’m wondering if there is any way that I might be over medicated and if this could in fact have the opposite effect and slow my heart? Could it be I’m not converting properly so despite the tsh just in the range it’s making me hyper?
Just trying to understand a bit more.
100mcg of Levo (I was on 125mcg for a time but the doctor wasn’t keen and then I self sourced t3 for a couple of years but couldn’t afford this or to have more private tests to monitor levels so have just been on 100mcg for the past 4 years.
Previously the private bloods showed antibodies
Anti-Thyroidperoxidase abs 29.6 <34 kIU/L
Anti-Thyroglobulin Abs H 359.9 <115
Blood results TSH range 0.4-5
7 April 2025 0.7 mIU/L
4 February 2025 0.8 mIU/L
16 October 2024 0.2 mIU/L
25 January 2024 0.7 mIU/L
2 October 2023 0.9 mIU/L
31 August 2022 0.4 mIU/L
8 October 2021 0.7 mIU/L
8 October 2021 0.7 mIU/L
27 July 2021 0.2 mIU/L
27 July 2021 0.2 mIU/L
27 April 2021 < 0.05 mIU/L
17 March 2021 0.2 mIU/L
14 October 2020 0.2 mIU/L
T4 range 9-19
7 April 2025 13 pmol/L
25 January 2024 15 pmol/L
31 August 2022 12 pmol/L
8 October 2021 13 pmol/L
8 October 2021 13 pmol/L
27 July 2021 13 pmol/L
27 July 2021 13 pmol/L
27 April 2021 16 pmol/L
17 March 2021 16 pmol/L
14 October 2020 15 pmol/L
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pinklady756
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A slow heart rate is more likely to be UNDER medication than over, in so far as it’s related to your thyroid. Mine dropped to the low 40s and occasionally into the middle 30s before I started with levo, I felt really rough. How are you feeling?
As Slowdragon says below, your T4 level is only 40% through the range, however with a TSH rocking along almost at the bottom of the range then your GP is going to say you’re adequately medicated, regardless of symptoms. Your best bet might be to discuss with your cardiologist, see if they’ll refer you for full thyroid testing to see your T3 levels (or even if they can do the testing) for potentially having T3 prescribed.
If you normally take levothyroxine at bedtime/in night ...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
IMPORTANT......If you are taking vitamin B complex, or any supplements containing biotin, remember to stop these 3-5 days before ALL BLOOD TESTS , as biotin can falsely affect test results
In days 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 if last test result serum B12 was below 500 or active B12 (private test) under 70
Do you always get same brand of levothyroxine at each prescription
Come back with new post once you get thyroid and vitamin results
if GP still refuses to increase dose levothyroxine
Here’s link for how to request Thyroid U.K.list of private Doctors emailed to you, but within the email a link to download list of recommended thyroid specialist endocrinologists
Ideally choose an endocrinologist to see privately initially and who also does NHS consultations so that might eventually transfer to NHS
Thanks for your replies, I’ve not had ferritin etc checked since last May so I’ve spoken to gp today and booked for bloods in 2 weeks. He says he doesn’t think this is anything endocrine and to see what the cardiologist says. Exactly as m someone else said they’re happy that thyroid is fine 🙈
Always the same brand of Levo. Tests always first thing after stopped medication as per advice
They’re not repeating thyroid so I’m going to look at private test to check t3 etc.
I find my resting pulse correlates so closely with my thyroid status it can be as reliable as a blood test for monitoring and adjusting levothyroxine dose. It sits low 60's when symptom free. If it goes down into the 50's symptoms return and I know it's time to adjust
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Thoughts on thyroid results?
Why would SMALL increase in T3 meds have caused fT3 to go DOWN a LOT and fT4 to also go DOWN? 
Very Low TSH but symptoms much better. 
Latest blood results advice please
