Heart rate after levothyroxine increase

[Fweb]

Hello all

I recently got myself a private endocrinologist appointment after being increasingly frustrated by GPs being dismissive, and not wanting to increase my levothyroxine as my levels were "normal" despite still experiencing a lot of symptoms. I'm so glad I did, because she was very kind, completely validated me in what I was feeling, and as I was told on this forum agreed my TSH should be below 2 rather than below 5 if I am on levothyroxine. Based on the Monitor My Health test results I took with me, she wrote to my GP to ask them to up my prescription to 100mg a day, and I've now been on that dose for about 2 weeks (got repeat bloods and a follow up appointment in a few weeks). Also in line with what kind people on this forum have told me, she has booked me in for a coeliac test and a bunch of other things I now can't remember (cortisol and other autoimmune markers I think?), so overall just feel a lot better that things are in motion a bit more. So thank you for all the advice on here

Onto my actual question. I've now been taking 100mg levo a day for a bit over 2 weeks, and I have to say the difference in symptoms has been massive. Definitely over the last week, I just feel more human - I'm feeling more productive and less brain useless at work, I'm doing more physical activity without getting exhausted, my gastro symptoms have improved etc etc. However my heart rate has been higher, and having some palpitations which I understand can be a side effect of the levo. Given I feel much better in general, I'm hoping that this is something that will pass? Has anyone had this and found that it levelled out with time? Or did you need to drop down a levo dose?

Thank you

[humanbean]

However my heart rate has been higher, and having some palpitations which I understand can be a side effect of the levo. Given I feel much better in general, I'm hoping that this is something that will pass?

We really need some numbers. What was your heart rate before your increase and what is it now?

Palpitations and a fast heart rate can be a consequence of low iron and/or low ferritin (iron stores).

It can also be a result of changing your dose and it could settle down over the next few weeks.

It can be a result of poor conversion from T4 to T3. i.e. if Free T3 is too low for your well-being.

Too high a level of FreeT3 can cause issues with the heart rate and could also cause palpitations.

I'd give the new dose at least another few weeks if you can cope with it then do a thyroid function test including TSH, Free T4 and Free T3.

Another thing you can try...

Try changing the time that you take your Levo. When I was in the first stages of taking Levo I discovered that I couldn't cope with taking it first thing in the morning. I did a saliva cortisol test and discovered that my cortisol was over the range.

[But I could have found out what timing worked best without testing my cortisol - I just needed to experiment.]

I started taking my thyroid hormones when my cortisol was closest to optimal which was late morning or early afternoon, I can't remember exactly now. I also tried splitting my dose throughout the day as well. At one point I was splitting everything into 5 miniscule doses per day.

In my case my problems were caused by very low iron/ferritin and very high cortisol. As I improved those my problems with taking thyroid hormones reduced. I now take them once a day.

[Fweb in reply to humanbean]

Thank you for this In terms of numbers, my resting heart rate/when I was asleep was consistently low 60s, but in the last week and a bit has been showing consistently low 70s. Can also see that my heart rate seems to spike a lot more doing "normal" things than it did before the levo increase, e.g. my Fitbit shows a spike to 140 BPM this morning when all I was doing was putting some washing outside. I keep just being aware of my heart "doing things" when I'm not doing much, but then again may also be a bit of a case of I'm more aware of it from seeing these numbers.

I have been taking a iron supplement too, as the last MMH I did about a month ago showed ferritin as low end of normal (33 ug/L). So hopefully between that and maybe my body adjusting to the dose, things may settle down as you say.

The timing of taking the levothyroxine aspect is interesting and would make a lot of sense. I've been thinking about maybe swapping to taking it in the evening, but hadn't really crossed my mind that could work better at other times of day too. Thank you for sharing and glad you are having less problems with taking it now

[DippyDame]

One thing I've become aware of is that as the dose increase resolves symptoms there is a healing process at work and during that healing process, heart rate and blood pressure can rise temporarily.

Every cell in the body needs to be flooded with T3 by way of a constant and adequate supply....if T3 level is low we experience ill health.

It takes time!

Your raised levo dose will be converting and producing more serum T3 which, in turn ( if all things are equal) will become cellular T3. This then becomes active as it reaches the nuclei of the cells, attaches to T3 receptors and does what the body requires of it.

All this requires effort by the body....we tend to forget that!

This could be what you are experiencing and given time and the right conditions things should settle again

Our bodies need time off/ rest to allow us to recover but with busy lives this doesn't always happen so we push on and recovery takes longer...and the body reacts to that.

An old medic friend used to tell me that we must learn to listen to our body and understand when it needs help ....and then work out what in our life is causing us to feel unwell!

I'd suggest you give the new dose time to settle before you consider changing anything....two weeks is not long enough. It takes 6 to 8 weeks!

Test again after 6/8 weeks on a steady dose of 100mcg....the results will point the way forward

It sounds as if you are heading in the right direction just give your body a helping hand by taking things easy and being kind to it while it makes the necessary adjustments

[Fweb in reply to DippyDame]

Thank you for this I think you are very right, I need to allow my body some time to adjust to this and try to take things easier for a bit.