Hello I seem to get heart flutters when I’m due t3 after taking meds it settles down after a while anyone else have the same
T3 and palpitations : Hello I seem to get heart... - Thyroid UK
T3 and palpitations


This is a common experience, but it might mean that you need a slightly higher dose for your daily energy requirements, or that you need to reconsider the timing of your dose(s).
Ok thanks I’m on a high amount 160 to 185 per day
For me, it felt like the physiologicaly addictive nature of T3. So I cut back the T3 and increased the T4 , As much as I could bear. That helped.
It is very high amount per day. Your blood test result is OK with that dosage?
It is common side effect of T3. It is stronger than T4 in terms of same dose. (25mcg of T3 is equivalent of 75mcg-100mcg of T4)
It can cause fever and heart palpitation. T3 also increase liver enzyme while it is digested.
T3 is cortisol sensitive so it can increase adrenaline depending on dosage so increase heart beats or causes heart palpitation.
Synthetic T4 (levo) also keep adrenaline and cortisol high and then later (after a while) cortisol gets low and excess adrenaline is produced. The more T4 the faster heart beats and more heart palpitation and chest pain.
You should be careful with dosage of T3 and check other hormone (progesterone and estrogen) as it can cause estrogen dominance.
Hi thanks for responding I’ve been on a high dose for some time I don’t convert t4, lately I’ve had awful pains all over and acid reflux worse than ever so some say I’m under medicated!! It’s so difficult this condition I have a hiatus hernia which is common with hashi but although I get acid no way near as bad as lately
I'm T3 only and dose once in the morning. I tend to get that feeling in the evening as it starts to run out.