Hello, slightly worried about potential cardiac damage (could be totally overreacting!).
I'm 48 and have been on levothyroxine for abt 4 years (150mg). I'm pretty fit - though hardly athletic (top top end of healthy bmi) and run regularly. I wear a sports watch and occasionally when I'm bored check my resting heart rate. It's always been pretty low - around 55 but today it has dropped to 47. I'm worried because when I run it can jump to 170/174 top.
I'm wondering whether the levo is not doing its job and I'm weakening my heart? Or whether I could have irregular heart beat? I did have a murmur years ago but no issues came of it - just picked up routinely.
I feel as well as a peri menopausal, working mother can!
Any advice gratefully listened to.
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Flotsam
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If you are perimenopausal then ensure you have a calcium rich diet and plenty of nutritious food. Get enough weight bearing exercise daily to maintain bone and muscle strength. Make sure you get enough sunshine in the summer months.
What are your latest thyroid test results? Perhaps you are undermedicated?
Hi Flotsam, my hypothyroidism was only diagnosed, because like you, i wear a tracker and visited the docs, as i was concerned at my low heart rate. Resting HR 45/47. I did a bit of online googling and, it mentioned thyroid can cause low heart rate (bradycardia). Doc initially tried to say it was because i run a couple of times a week, lift a few hand weights etc. I had to request bloods and, specifically asked for my thyroid to be checked. Started on 25mg, made little difference. Now on 50mg and heart rates gone to 52/54. The docs said he’s not retesting me for three months, but rightly or wrongly, i’m basing whether my dosage is correct on my HR and if it doesn’t go up further, i’ll go back to the doc in a few weeks and insist on new bloods. (I’m just post menopausal). My Dad is end stage heart failure, under the same doc as me, so you’d think my heart concerns would have been considered more. Maybe if your bloods are rechecked you might get more clarity. All doctors have got these 24 hour HR monitors too, which they use to check for heart irregularities etc. Could you request one to put your mind at rest?
Hi Daniel - excuse my ignorance but where do I get d3 and taurine from? How did you realise it wasn't a good thing to have low heart rate? Did you see GP?
Gp advised it was low - had never questioned it before
I have only been slightly low on d3 from tests and only used the tiniest dose in the last- decided to up to 2000iu and I will retest d levels again at some point.
I’m surprised taurine gets so little mention here - there is some great research out there ....
Thanks Read58 - interesting. Was your doc concerned at your bradycardia? You would think they would be as doesn't it weaken your heart? That's my worry. Your dose sounds very low. 50mg is a starting dose really. Do you feel better?
I feel ok, which is why I'm surprised - I dont think im undermedicated.
Re the heart rate - is yours consistently low at rest? Mine is higher when im lying down and lower when sitting/standing.
Hi Flotsam, doc didn’t seem concerned at all, which for some people would reassure them, but because of my long family history of inherited heart problems, i will make sure its not ignored. To be honest, i’ve been brought up with a pretty much ‘grin and bear’ it attitude, so i’ve just felt that feeling like cxxp,for as long as i can remember, is my cross to bear. (Put it all down to the menopause, caring for dying father, etc). Don’t feel any different on 50mg than before i started taking it, which was only September this year. Like you, when i’m lying down, HR slightly higher, 58/60
Now on 50mg and heart rates gone to 52/54. The docs said he’s not retesting me for three months, but rightly or wrongly, i’m basing whether my dosage is correct on my HR and if it doesn’t go up further, i’ll go back to the doc in a few weeks and insist on new bloods.
There is no justification for your doctor to make you wait for three months before re-testing you (other than the doctor's budget, I suspect). People should be tested every 6 weeks and an increase of 25mcg given if TSH is still high. Your current dose is just a starter dose for most people, it isn't a treatment dose. Most of us need a TSH of 1 or below to feel well.
If your thyroid was still capable of producing thyroid hormone before treatment, then starting treatment with levo will probably reduce its output. This is why so many people feel worse after beginning treatment - they actually end up with less T4 and less T3 than they had before because their thyroid gives up, until their dose is raised high enough.
I don't know what guidelines for treatment your doctor is using (probably guidelines from your local CCG), but you might find this of some use :
It links to the Clinical Knowledge Summary for hypothyroidism produced by NICE. You can click on the various links down the left hand side of the page to get the recommendations for various scenarios. Unfortunately, I think your doctor will dismiss the NICE recommendations, but it is worth reading.
A Free T4 of 8 with a reference range of 8 - 19 is NOT normal. The number of healthy people with a Free T4 of 8 and who also feel healthy would be vanishingly small.
Doctors get almost no training in statistics, and it shows. Your TSH of 17 is far, far, far too high, and to leave you suffering for three months is cruel and unusual punishment for being hypothyroid.
That TSH is way too high..I cant understand why your gp isn't just incrementally increasing it. Poor you. You probably feel.crap (never mind sick parents and menopause)
Agree totally with Humanbean that you should not wait for 3 months before retesting and upping dose of levothyroxine. TSH of 17 is way too high to feel well. FT4 of 8, right at the bottom of your lab range is not normal. It shows you do not have enough thyroid hormone for your body to function efficiently.
Someone who was healthy with normal thyroid function would have an FT4 nearer to the top of the FT4 range or at least mid-lab-range. The top of your lab range for FT4 is 19 so from my experience as a fellow thyroid patient, your FT4 would be expected to be between 14 and 19 and your TSH nearer to 1.0 if you had enough thyroid hormone in your body.
Thank you for all this info. Believe me I need it! I’ve always thought i was of pretty regular intelligence, until i started to try and get my head around thyroid stats! Getting invaluable knowledge from the posts you guys contribute.
Insist of blood tests 6-8 weeks after each dose increase
Dose of Levothyroxine should be increased in 25mcg steps until TSH is around one and FT4 towards top of range and FT3 at least half way in range
Also, get vitamin D, folate, B12 and ferritin plus both TPO and TG antibodies tested by GP or privately
For full Thyroid evaluation you need TSH, FT4, FT3 plus TPO and TG thyroid antibodies and also very important to test vitamin D, folate, ferritin and B12
Private tests are available. Thousands on here forced to do this as NHS often refuses to test FT3 or antibodies or vitamins
Medichecks Thyroid plus ultra vitamin or Blue Horizon Thyroid plus eleven are the most popular choice. DIY finger prick test or option to pay extra for private blood draw. Both companies often have money off offers.
All thyroid tests should ideally be done as early as possible in morning and fasting. When on Levothyroxine, take last dose 24 hours prior to test, and take next dose straight after test. This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, GP will be unaware)
My heart rate was really low - just under or over 40. Had ECG for palpitations and nurse asked me if it was always so low but doc was totally unworried. T4 has now increased rate to more normal range -50s. But yeah docs don’t seem too interested. Nor are they interested in body temp being any kind of measure.
No, it often feels that they've little interest at all in low heart rate, body temps... general feelings of being unwell/fatigue, etc... once standard hypothyroid signs/symptoms. xox
Do you have recent blood test results......including FT3?
You are legally entitled to printed copies of your blood test results and ranges.
UK GP practices are supposed to offer online access for blood test results. Ring and ask if this is available and apply to do so if possible, if it is you may need "enhanced access" to see blood results.
In reality many GP surgeries do not have blood test results online yet
Alternatively ring receptionist and request printed copies of results. Allow couple of days and then go and pick up. They can no longer charge for printing out, rules changed after May 25th 2018
It's common for our ability to convert FT4 to FT3 to deminish as get older or due to low vitamins
Your heart valve, was this mitral valve ? Common with Hashimoto's, autoimmune thyroid disease
For full Thyroid evaluation you need TSH, FT4, FT3 plus TPO and TG thyroid antibodies and also very important to test vitamin D, folate, ferritin and B12
Private tests are available. Thousands on here forced to do this as NHS often refuses to test FT3 or antibodies or vitamins
Medichecks Thyroid plus ultra vitamin or Blue Horizon Thyroid plus eleven are the most popular choice. DIY finger prick test or option to pay extra for private blood draw. Both companies often have money off offers.
All thyroid tests should ideally be done as early as possible in morning and fasting.
Come back with new post once you have results and ranges
Thanks slowdragon - really useful info. I may have no choice but to pursue privately. GPs seem as disinterested in thyroid as they are in menopause. No offence. It's probably lack of time and resources. Quality of life is way down on their list...
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