Can anybody help? I have noticed a distinct correlation between my resting heart rate decreasing when taking Levothyroxine. I am on a very low dose 25mcg which should be going up in the next couple of days awaiting for blood results and realise I am still under medicated. Over the past year I have been up to 75mcg and back to 0 due to some horrible symptoms/side effects.
I have had a fit bit for a year and having restarted again on Levothyroxine after 4 months off (long story on other post!) my resting heart rate has dropped by almost 10 beats per minute which it did before. At night my heart rate drops to 44bpm! During the day when relaxed it’s 55. I’m starting to think the ongoing symptoms of twitches and pins and needles I experience when on Levothyroxine could be circulatory? I could be completely wrong but wandered if anybody else experienced the same? Should I be concerned!
I understand low pulse is related to hypothyroidism could it just be getting worse due to being under medicated?
I’m a 36 year old fairly active working mum of four so hoping my heart isn’t about to give up!
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Tiff35
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My bp and pulse goes down when I am better medicated re hypothyroidism, but mine otherwise are both high when undermedicated, so not an unknown phenomena!
When we take only a small dose of Levothyroxine this doesn't "add" to our own thyroid output. The body sees the small dose of Levothyroxine, the TSH drops, and our own thyroid takes a holiday and reduces output
Hence the recommended starter dose is 50mcgs. Bloods retested 6-8 weeks after each dose increase. Dose increased upwards slowly in 25mcg steps, retesting each time
Typically patients need somewhere between 100mcg and 200mcg Levothyroxine daily
For most people: 50–100 micrograms once daily, preferably taken at least 30 minutes before breakfast, caffeine-containing liquids (such as coffee or tea), or other drugs.
* This should be adjusted in increments of 25–50 micrograms every 3–4 weeks according to response. The usual maintenance dose is 100–200 micrograms once daily."
Low vitamins are extremely common especially if cause of hypothyroidism is due to autoimmune thyroid disease also called Hashimoto's diagnosed by high thyroid antibodies
Essential to regularly test vitamin D, folate, ferritin and B12
Many patients need to supplement some or all of these regularly to maintain optimal levels
Ask GP to test vitamins and antibodies if not been done
Add results and ranges if you have them
For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested. Also extremely important to test vitamin D, folate, ferritin and B12
Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and fasting. Do not take Levothyroxine dose in the 24 hours prior to test, delay and take immediately after blood draw. This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)
Is this how you do your tests?
Private tests are available. Thousands on here forced to do this as NHS often refuses to test FT3 or antibodies or all 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 special offers, Medichecks usually have offers on Thursdays, Blue Horizon its more random
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