Hi all, I was started on liothyronine only 6 months ago and it has been life changing. It has resolved 4 years of debilitating symptoms, including chronic fatigue. I have faulty D102 and am a poor converter. I was finally taken off levothyroxine following abnormal ECG and tachycardia. I had a scan and 7 day trace which was within normal limits ( before liothyronine) I started slowly on 5mg and am now on 40mcg per day which is taken as 10mcg capsules x 4 per day. I am quite light weight-wise which is why endo hasn't increased.
I am experiencing higher resting heart rate than I ever had. My normal a year ago would have been 65. It is now usually between 80-91 and sometimes higher. My blood pressure is normal range although higher than it was previously. I am a little concerned about whether the liothyronine is causing this and what the long term impact might be on my heart health . I tried to reduce to 30mcg as a trial but quickly became hypo. My heart rate did lower down into the 70s though. Anyone else experience this?
Also advised I'm at higher risk of osteoporosis. Should I be supplementing calcium? Thanks.
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Mhaire
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For me personally as a person who also only uses T3, if my heart rate increases and I feel slight anxiety, I reduce my dose by roughly 5-6 mcg and see how I feel after a couple of days. This often happens in the summer months when i find i need slightly less. But of course everyone is different.
Thanks. I've been given 10mcg capsules. Because I was prescribed 40mcg, the chemist stopped giving me tablets, which I could split to adjust. Think it was the cost. I do think that trialling small dose adjustments might help me find out what works. I've been told heart rate still within normal range but it feel uncomfortable to me and races at night when I'm sleeping. Endo told me to tske propanalol but I think it might affect uptake
Actually I haven't felt as well on 10 mcg capsules as I did when I was on 5mcg and there's no abilty to adjust dose smaller amounts. They did give me a 20mcg tablet at a time but you couldn't spilt it. Is there a brand tablet at 10mcg you can split? It's nhs so I suppose I am tied to whst they are prepared to dispense st pharmacy
Also advised I'm at higher risk of osteoporosis. Should I be supplementing calcium?
Because you're taking T3? Only if you take too much, and I very much doubt you are taking too much on only 40 mcg a day.
And I really don't think you should supplement calcium, no. And certainly not without getting it tested first.
Calcium is neither a prevention, a treatment nor a cure for osteoporosis. And too much can be dangerous. Calcium supplements are difficult to absorb and tend to build up in the soft tissues and arteries. And excess can make bones brittle.
Vit D and magnesium are far more important for bones than calcium. Have you had your vit D tested?
Do you get your FT3 tested regularly? When on T3 mono-therapy symptoms are more important than blood tests, but it's a good idea to keep an eye on levels, all the same - especially in the beginning until you get used to taking it. And to see how well you are absorbing it. Taking it four times a day must make it difficult to take away from food and supplements. So, it might possibly be a better idea to take it less often and absorb more. But you'd have to have it tested regularly to know if that would work.
Really reassuring re osteoporosis risk, thank you. It is really hard being tied to 4 times a day but i cant seem to manage without that 10pm dose before bed . Maybe my overall dose isnt high enough and if it was i could cut down on frequency of dosing. I take it at 5am, 12md 5pm and 10pm. When i tried 20 it seemed too much for me in the space of 6 hours. Mayve i should have perservered. Its so hard to know what to do. Yes, I get my T3 checked and endo said it was slightly high last time but want to monitor. What should I do about timing of T3 blood test? Should I stop dosing 12 hours before? Hospital phlebotomy has booked me for 2pm so I would miss two doses. Is this too late for T3 tests, or does it work differently than when on levo?
I take a good quality Vit D and K2 and B complex and individual magnesium, zinc, selenium. I should prob get tested to keep an eye anyway, though.
The last dose of T3 should be 8 to 12 hours before the blood test if you don't want a false high.
T3 isn't much affected by the time of day. And the advice to test early is to get the highst TSH. As your TSH is going to be low anyway on 40 mcg T3, it doesn't really matter what time of day you do the test.
This is great information. I will stick to blood test time and just skip those two doses. I think I will try this dosing and taking on board what sparkly has said below as well I think I'll speak to gp/pharmacy to change to tablets and try this out. What great information from you all thank you
I'd like to know about this too as I don't know what is classed as an acceptable increased hr when on t3 only.I'm concerned when my rhr daily average increases on my fitbit when I increase my dose to try eliveate symptoms.
I know my pulse could be as low as high 50's at points in day before diagnosed (time before fitbits) but now having a fitbit you can become I bit obsessed with keeping an eye on it because its so easy to do so. My rh will vary between low 70's to 110 ish on normal days and then upto 150 when at gym.
My bp is normal now due to exercise.
It doesn't help that I have white coat syndrome and my bp and pulse are always up with any medical appointment 🤦🏼♀️
When I first started liothyronine, I took before and after blood pressure and heart rate readings to try and understand what was going on. Heart rate went up and blood pressure went down before dosing. There was a definite pattern which suggested to me that my body needed T3, as it seemed to settle after dosing. I had no reserves at that point and still very unwell. My resting heart rate has come down overall from 6 months ago as it was 120-135 at times, nd that was in bed at night. My cortisol curve was back to front though. My dr prescribed propanalol but I'd rather not have to take more tablets if I can help it
I think perhaps 4 doses is too much and you're not getting enough at once. I think GG is right on taking 3 doses. You say you can't be without your 10pm dose is this because you feel awful without and can't sleep and do you feel this dose decrease your hr? I know if my single morning dose is too low that is what happens to me. I then have to take another 20mcg and within an hour or less I feel normal then can sleep. I am a bit complex though
I think you are right. Perhaps I'm not getting big enough dose in day to sustain me. The pattern has been that if I don't top up with 10mcg at 9-10 ish, by 1-2am I am getting hypo and restless and heart rate increases. Sometimes woken out of sleep and have to sit on edge of bed to settle my heart rate. Sometimes have taken an extra T3 to settle it but thst puts the next dsy out of synch. Its not menopause related, as I had thought, and I'm very stable on HRT. I too am very complex and not a straightforward journey for me
As I thought, I am the same. I can only take t3 in one morning dose. I try every year to split it but after 4 days I'm floored and feel like I'm not taking anything.
The heart is extremely reliant on getting the exact amount of T3. Those medicating T4/T3 combo will have capacity for small variations dictated by what the body needs, though mechanisms such as hormone transporters, increased/decreased conversion, etc, designed to aid control of thyroid hormone amounts.
Medicating T3-only eliminates these variations (eg you only have the amount you medicate) and so any movement away from your exact T3 sweetspot may be felt by a heart already vulnerable through previous lack of adequate thyroid hormone levels.
You are only at risk of osteoporosis if you are medicating excess T3 that speeds up resorption faster than the bone is formed, resulting in a net loss and bone thinning. Research shows a clean healthy diet provides enough calcium that is better utilised by the body than supplemented calcium that risks buildup in the arteries. Improved bone health can also be encouraged through use of Vit D, adequate and balanced sex hormones (particularly oestrogen & progesterone in ladies).
Thank you for your expertise Radd. This is so interesting and now that I understand, I can put the osteoporosis risk in context.It's been such a long and lonely journey and now a new phase with T3 only. Trying to understand the increased heart rate and coping with the huhh HR and palpitations has been pretty exhausting. I always thought it was lack of thyroid hormone but was told by doctors liothyronine was likely speeding up my heart rate and just add propanalol. Actually, the propanalol didn't make much difference when I took it and I don't want yo put a plaster on or mask something I can fix or tweak.
So last night I was up most of the night restless with a heart rate of 122. This morning I decided to dilute the 10mcg capsule, delay taking my dose until 8am, and increase to 15mcg.
My heart rate has come down to 65 and has stayed down!! I can't believe it. I feel calmer and better. That is the first time since starting T3 that my resting heart rate has returned to normal.
Im going to trial 15 +15 + 10 on greygoose's and others advice. Obviously, I haven't been getting enough thyroid hormone at the right time for my heart. Thank you all. This site and community is invaluable and I really appreciate everyone who took the time to respond to me.
Mhaire I broadly have a similar problem. Please keep posting. I might DM you with some questions. I have not had the courage to do what you have done. Upping your T3 whilst suffering tachycardia. Well done you!
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