I started T3 6 days ago. I’ve been prescribed 10 mcg split into two doses of 5mcg. So far I’ve only taken 5mcg per day. For the first 4 days I took my Levo in the morning and the Lio early afternoon. That felt fine. For the last 2 days I’ve taken the lio with the Levo in the morning, intending to take the second dose of lio in the afternoon but my heart rate has risen and any exercise at all sends it shooting up. Yesterday it went to 170, while lugging my Christmas suitcase up a load of steps to find a bus replacement service 😳. I don’t like that at all So I haven’t taken a second dose of Lio yet.
My question is whether increased heart rate is one of those things that might ‘settle’ as my body gets used to the Lio or whether that’s simply how some bodies respond. If the latter I probably won’t try increasing to 10mcg.
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Pearlteapot
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Hi Pearl, mine settled, I would just hold off adding another dose until it has, it is a bit shocking when your heart rate increases but if like me you have been deficient of T3 for any length of time you have likely been on a slow/weak tick over 🤗
Checking your resting heart rate is a good indicator, mine increased by 4-5bpm to actually a more 'normal' tick over when adding T3, it does speed up your metabolism
it’s true that I’m used to a very low, sub 50, resting heart rate, so a bit shocked by 64bpm which is more normal. It’s the spikes if I do errands up and down the stairs that freak me out, to over 100 while doing not much. I know these are ‘normal’ parameters but a massive change for me. I’m glad to hear you initially had a high rate but it settled. I shall wait and see before taking the extra 5.
One thing I will say is that I have a mental clarity that I have lacked for well over a year, perhaps two
You may need an EEG to rule out Atrial Fibrillation. You may also find that magnesium helps (which is a treatment for atrial fib), but AF can be serious, so I would not increase the dose until you feel settled and have ruled AF out.
You don't mention how much levo you reduced by and when? If you have reduced levo in the last 2 weeks it will still be in your system and will slowly reduce naturally to your new dose level. During this time you might get a higher heart rate.
interesting, you attribute the heart rate to the Levo. My consultant reduced the Levo from 150 to 125, which I did for 10 days before adding t3. But I was overmedicated on 150 and this forum, advised going down to 100 before starting t3. I stuck with the 125 that the consultant said but yesterday when I took the 125 at the same time as the Lio I felt overmedicated and this morning went down to 100 Levo. I’m going to stick at 100 until testing. Perhaps the reduction in Levo will settle my heart do you think?
I'd need to look back at your blood results but it might be safer to drop to 100mcgs levo. You can explain later to your consultant. Levo may well be playing a part.
Looking at these you were pretty under replaced on 112.5mcgs. Are there any blood results when you were on 150mcgs? I'm wondering if you're mainly suffering from hypo symptoms now.
So the November results on 150mcgs is more of an 'optimal' result on Levo alone. It could be that the low FT3 isn't suiting you and you're suffering from hypo symptoms which can feel like being hyper for some.
I think I saw that your vitamins were optimal so just stick with it and try and ride the symptoms out while your levels are too low.
I always follow the ‘low and slow’ mantra, as increasing thyroid medication too quickly always increases my heart rate & gives me palpitations. I find a pill cutter handy for splitting tablets so I can increase Liothyronine by 2.5mcg.
if your t3 has been very low, you will be more sensitive to it and react to the change in level of t3, rather than the amount. It’s possible that if you take a second dose your body will become more used to the t3 being higher and you’ll be less sensitive to it and so get fewer palpitations. In your situation I’d take the Levo at bedtime, and t3 in morning and afternoon to spread it out.
when I introduced T3 I was on 75mcg levo a day. I also take 5mcg T3 in the morning and also 5mcg 8 hrs later about 3pm. I found splitting my levo dose really helped too as I found I couldn’t take it in one dose anymore as I’d feel over medicated within an hour after ingesting. See if splitting your levo as well as the lio helps. It did me. I now feel fully energised and youthful for my age 64. I go the gym 3 times a week now from being in a place where I could barely walk. My heart rate can go quite high. I wear an apple Nike watch and monitor it. Looking at the year it ranges from 40-176 and that’s just brisk walking mainly. I feel absolutely fine though. 40 is rather low. Normally my resting heart rate is about 55bpm. When I’m feeling over medicated my resting heart rate drops not goes up. This can happen with over medicating on levo as well as lio. I tend to keep my levo level just below mid way and same for lio. I think it’s best to have an adequate amount of each rather than overloading and flooding my system. Our bodies naturally don’t overload. My TSH is always just about in range too. This helps as Drs are pleased and will continue to prescribe without hesitation. Try splitting both medications.
thanks. This is another option to Aurealis suggestion of taking the Levo at night and T3 in the day (which I am trying today). Good to know that others felt overmedicated by taking it all at the same time, and that separating the Levo out can help.
Hopefully I’ll feel good all day Christmas Day today. I went for a night walk across the fields last night and saw a white barn owl fly overhead Happy Christmas all and thanks for the comments and suggestions.
After my recent similar experience I would not ‘leave it to settle’ by taking more meds. It’s such an unpleasant experience. I would either cut back (with hindsight) or space it out, maybe missing alternate days (or even more) until I am sure it has indeed settled and certainly do not add the next dose until you are sure there is no upset. I felt so good mentally particularly, I steamed on ahead until the racing heart. Now I have had to return to the original dose I started from, probably putting myself back about six weeks at least! I am pretty annoyed with myself and now I really am having to reign myself in! Happy Christmas Pearlteapot.
I have always taken one daily dose of T3 when I awake along with one glass of water and wait an hou before I eat.
According to Dr John Lowe - when our T3 cells are saturated that they, in turn, send out 'waves ' throughout the day.
At present my dose is 20mcg. once daily and I don't have any unpleasant symptoms. I am also energetic and symptom-free.
I don't eat anything until one hour has elapsed between dose of T3 and I feel well and have no clinical symptoms .
I follow the guidelines by Dr John Lowe, doctor, researcher and expert about T3 (liothyronine) and he was also an Adviser to Thyroiduk before he died due to an accident.
The fact that he was a 'researcher/scientist/expert on T3' he couldn't bear the fact that so many people were suffering due to not having doctors who were knowledgeable enough to assist patients to good health.
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T3 increasing my heart rate? Help please feel awful! 
Decreasing resting heart rate (post TT, combo T4/T3)
