Upped liothyronine dosage- side effects - Thyroid UK

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Upped liothyronine dosage- side effects

ReneeC76 profile image
16 Replies

Hi again, everyone. In another post, I mentioned having some severe hypothyroid symptoms. I had RAI for graves a year ago and taking 50 mcg levo and 5 mcg liothyronine per day. I've had some wonderful advice/suggestions from some great people here and I also emailed my doctor yesterday to ask about increasing the lio dosage. He agreed and said go up to 5 mcg twice per day. I did that yesterday and last night my heart went wild and woke me up out of sleep. Beating very rapidly.

It's been beating rapidly since and it's uncomfortable. I'm guessing I should not skip a dose of the lio, but wondering if I possibly should back down the dosage again just a bit. I can always cut a pill in half if need be. I'm due to take my next dose pretty soon and wondered what anyone's thoughts might be. My hypo symptoms do feel better... now I have this fast heartbeat. Did email the dr again but got an automated reply he's out of the office for a couple weeks. Of course.

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16 Replies
SeasideSusie profile image
SeasideSusieRemembering

Have you taken 5mcg T3 this morning?

Still have fast heartbeat?

If so, if that was me I'd skip the dose later today.

Heart rate should settle, if so just take 5mcg daily for a couple of days to make sure things have stabilised.

Then I'd try an increase of 2.5mcg, so your usual 5mcg in the morning and 2.5mcg later in the day, see how that goes.

ReneeC76 profile image
ReneeC76 in reply toSeasideSusie

I'm to take the morning dose in about a half hour. Your advice sounds reasonable. I want to get my heart calmed down but also don't want to crash back into the awful hypo stuff.

SeasideSusie profile image
SeasideSusieRemembering in reply toReneeC76

Ah, so not in the UK then?

If your heart is still racing now, then I'd skip the dose you're due at the moment. Give your heart time to calm down. You may only need to skip a couple of doses, then reintroduce at 5mcg, if things are nicely settled on that dose after a couple of days then introduce the extra 2.5mcg.

ReneeC76 profile image
ReneeC76 in reply toSeasideSusie

No, I'm in the US. I'm taking my first dose a little later in the morning than I'd like just because when I started I was in the hospital and that's the time they started me. I suppose once I get things settled I can start taking my dose earlier. That sounds good, yes it seems I need to get my heart some time to slow down a bit. I feel pretty fatigued already, I know the T3 is wearing down from yesterday but at the same time I'm sure my heart needs to slowly get used to this change.

Barrett582 profile image
Barrett582

I have found that I can’t take my T3 in two doses. I have to divide mine into three doses. When I first started T3, I had to up the dose by 2.5mcg at a time. I spent at least 3 or 4 weeks on each dose increase to stabilize. I now take 15mcg in three 5mcg dose. My heart rate goes up with any dose change (up or down) of T3 or T4. As unpleasant as this is when changing doses, my heart is quite calm at a proper dose for me. So it does make it easier to find your proper dose. Please feel free to ask questions. Good luck .

ReneeC76 profile image
ReneeC76 in reply toBarrett582

That's good information to know. I'm actually considering dividing mine into three or four doses rather than two. Rapid heart rate scares me and is so uncomfortable. Especially getting woke up in the middle of the night from it. I'm just trying to avoid it. Maybe that isn't possible, I don't know.

I do have one question, do you know if it would be common to feel rapid heartbeat and other side effects of liothyronine a full day or 2 after taking it? Or would those side effects more likely be that same day, considering T3 is absorbed so rapidly? Online, I'm seeing varying opinions about the half-life and so forth. I'm just trying to understand everything I can about this hormone, and I lost faith in my doctors, unfortunately.

Barrett582 profile image
Barrett582 in reply toReneeC76

All of this really depends on the individual. My heart rate can stay up for two days. How high is your heart rate and is it staying constantly high? When my ex-Endo lower my dose of T3 my heart rate went up. I could feel that just to make coffee in the morning I was running on adrenaline. Others on here know much more about adrenals than I do.

There are prescription meds that will lower your heart rate ( like inderal). Unfortunately you need a prescription. People (ie doctors) take this to calm themselves before speaking to a group. You can take it as needed. The problem is that you don’t know if the doctor will stop the T3. I have never tried it , but hawthorn tea is supposed to help with heart rate.

I will say that until you are completely stable on a dose of T4 and/ or T3 do NOT change manufacturers. I got incredibly fast heart rate with a change from Mayne to SigmaPharm. Now that I have been stable for over a year, I can take either.

ReneeC76 profile image
ReneeC76 in reply toBarrett582

I also have other questions for you, do you take T3 only or T3/T4 combo? And are you happy with taking T3?

Barrett582 profile image
Barrett582 in reply toReneeC76

I was diagnosed in 1995. I took only T4 for a while. About two years later, I started Armour. I was very happy with NDT(Armour) until it was reformulated in 2008. I now take 50mcg of T4 right before bed. I take 5mcg T3 at 6:30am, 5mcg T3 at 10:00am, and 5mcg at 1:00pm. This works for me after much trial and error. I am extremely happy taking T3. I have alarms set on my phone and I put the day’s T3 in a tiny essential oil bottle every morning. I put the bottle in my pocket and also have a small bottle full in my purse. I also eat with my T3 (not my T4). If I don’t eat it hits me hard. Since I always eat, my dose is titrated with food. I do have “bad genetics” for deiodinases 1 and 2. I have Hashimotos and no thyroid left. On only T4 my T4 is fine, my TSH is acceptable to doctor, and my T3 is way out of range. Without T3 my life is not worth living. It is very hard and slow for each person as an individual to get their proper dose and timing for T3. Unfortunately I have arrived at all of this very slowly. Please ask any questions you have, this can be a very difficult process.

ReneeC76 profile image
ReneeC76 in reply toBarrett582

Thank you so much for your advice. And for sharing what you've been through. Yes, I'm noticing that everyone is very very different when it comes to their situations. Your journey has been much longer than mine, but somewhat similar as far as the meds, I started on T4 only as well. I was not happy with this. I wanted Armour but my doctor said he wanted me to do levo/lio. I'm being very optimistic about this. Especially after talking to you and others here who like this combo.

It's unfortunate they changed Armour. It really is a shame the new formulation is inferior. It seems a lot of people feel that way. But I am glad you are happy with what you take now.

You mentioned adrenaline, I always forget that there is a chance that some of what I'm feeling is from adrenaline and not necessarily from the T3. Last night, my heart rate was up pretty high, I'm going to say 130 beats per minute at one point. But it was like an episode, that heart rate didn't last all night. It came down to about 90 to 95 which is high for me. Like I said, very uncomfortable, then I'm sure that throws off the adrenals and who knows what all.

Hawthorn tea, that's something I would be willing to try for sure. And maybe I do need to talk to the GP about meds to slow the heart rate.

You sound exactly like I plan to be with the T3! Setting alarms on my phone, carrying it with me. I really believe it's going to change my life for the better. At least I have to believe that right now!

Barrett582 profile image
Barrett582 in reply toReneeC76

You’re welcome. Ask any further questions that you might have. Just remember to go slowly.

ReneeC76 profile image
ReneeC76 in reply toBarrett582

Thank you, I sure will.

Barrett582 profile image
Barrett582 in reply toReneeC76

I forgot one important piece of advice. Always get print outs of your labs. Write on the print outs what exactly you were taking and when you were taking it. Also describe for yourself how you were feeling. I wish that I had done this throughout my journey. Also, your heart rate mirrors mine with the adrenaline in the mix. On a stable dosage my resting heart rate is 78-82 bpm. Good luck.

ReneeC76 profile image
ReneeC76 in reply toBarrett582

Excellent advice. I will do it. Thank you again.

Cat1957 profile image
Cat1957

Hi Renee,See if you can have your endocrinologist write a script for extended release liothyronine then have it filled at a compounding pharmacy. My heart is also sensitive to t3 so my endocrinologist writes me a script for the extended release liothronine. With the extended release, I don't experience the palpitations or racing heartrate.

pennyannie profile image
pennyannie in reply toCat1957

Are you aware you are replying to a 5 year old post ?

the O/P may have left the forum so don't be disappointed if you do not get a reply -

though a very good reply and possible solution for many forum members !!

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