After many years of misdiagnosis I have been taking 150 mcg of Levothroxine for about 30 years. Recently retired and bought a Fitbit only to find my heart is pumping around 90+ bpm and hits 120+ just doing normal stuff like walking. Had partial thyroid removal and initial 200 mcg reduced to 150 about 10 years ago.
Doc sent me to Cardio and he said all clear and recommended me for Endicro check and reduce tablets. 4 weeks on reduced dose and no great change, still waiting for Endocrinologist appointment. Still sleeping for Britain easily do 10 hours a night.
When I finally get to see a consultant anything I should be asking about, other than my rapid heart?
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Mazdaman1
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I had fast heart rate & palpitations when I was on 125mcg. I had been on that dose for 5 years without any problems but stress & hormone changes may have been the trigger for my hyperthyroid symptoms (fast heart & high bp).
I’ve now been on 75mcg for 18 months & I think I may now be hypo as I’ve developed tingling & numbness in my limbs & extremities.
I also started wearing a Fitbit last year & notice my heart rate is about 65 at rest but easily goes up to 120 on walking.
Not sure this is if any help but i think it’s good to keep a close tab on your thyroxine dose as the body’s needs seems to change over time.
I think you could very well be under-medicated. Why did your doctor reduce your levo? Do you have copies of your labs? If so, post them here. With ranges!
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.
If on Levothyroxine, don't take in the 24 hours prior to test, delay and take straight after
This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, GP will be unaware)
If antibodies are high this is Hashimoto's, (also known by medics here in UK more commonly as autoimmune thyroid disease).
About 90% of all hypothyroidism in Uk is due to Hashimoto's. Low vitamins are especially common with Hashimoto's. Food intolerances too, especially gluten. So it's important to get tested.
So a few weeks later I've had all the bloods done again, T3, T4, TRAK and all are good but heart still off like mad. The Cardio consultant signed me off as fine and recommended Endocrinologist but this is going to take months. If my thyroid tests are all clear then what is the point of seeing an Endocrinologis.
GP has reduced Levothroxine from 175 to 100 and now 75Mcg but with very little change over 2 months or so. Starting to worry that I'm going to run out of heart beats at this rate and don't know where to go next Cardio or Endro?
Have you had vitamin D, folate, ferritin and B12 tested
If not been done then you will need to ask GP to test or, like 1000's on here to FULL Thyroid and vitamin tests
If you have them can you add you actual results and ranges
HIGH heart rate can be because of under medication or poor conversion.
ALWAYS get actual results and ranges on all tests
Gluten free diet can help
Also look at DIO2 gene test. If you have this common gene variation then you will likely need addition of small dose of T3. This low T3 does NOT necessarily show in test results
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. If on Levothyroxine, don't take in the 24 hours prior to test, delay and take straight after. This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, GP will be unaware)
GP has reduced Levothroxine from 175 to 100 and now 75Mcg but with very little change over 2 months or so.
That is one huge reduction based on one supposed symptom. By which I mean, it isn't necessarily the levothyroxine that is the cause of your high heart rate. After all, if 175 was causing elevated heart rate, then even 150 would be expected to reduce it. By the time you got to 75 it almost proves it isn't the cause!
Assuming the cardio was confident of there being no obvious heart problems, it could well be worth checking out other possible causes such as infections, adrenal issues, etc. (I am no expert - just put in two known possibilities.)
Some years ago, I was found to have very high heart rate, which was a surprise to me because I had never noticed it! They had offered statins and beta-blockers but I never accepted them. A few weeks later, cardio did 24-hour monitor and a scan of my heart - all clear. Discharged.
I now have a cheap wrist band (Xiaomi Mi 2 - there is now the 3 available). Occasionally I hit 110 but mostly 59 to 95 - assuming it is accurate.
Have you tried manually taking your pulse as well, or asking if you can try a 24 hour monitor. I have read that fit bits aren't as accurate as we imagine but not having one mmyself I didn't take note of why. Plus our resting pulse is always going to be lower that walking.
Fast heart rate when exercising even walking is to be expected especially if your not very active or unfit, your best to check your testing heart rate before exercising.
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