I’m scared of my levothyroxine tablets I only take a small dose 25mg for hashimotos, I’ve been taking it for a week now since I last stopped them a couple of months ago and again i am feeling side effects. Loud heart at night and internal tremors and a bit short of breath. I just don’t know whether to carry on to see if it improves or stop it again. I don’t have a racing heart or anything or any chest pain
What do I do if I can’t tolerate levothyroxine? Or maybe this will get better who knows 🫣
TSH 12.10 range 0.27- 4.20
T4 10.7 range 11.1 - 22.6
GP didn’t do any other tests this time.
Thank you
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Fanakerpan
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Since your results show overt hypothyroidism you shouldn't have been started on such a low dose. The minimum should have been 50mg, possibly higher.
Symptoms on Levo are most common when dose is too high OR too low - and yours is clearly too low. Low nutrients will also increase symptoms, which I think has been discussed on your previous post.
Just to say I too am really nervous about my thyroid meds especially when it does unexpected things to my heart rate. Our hearts need the right amount of T3 to be happy - be it directly from T3 or converted from T4. And so your heart will be even more unhappy without the T3 ! I think you can take comfort from your ecg and a not-racing heart rate.
Slow and steady - and here is a great place for support if you need it.
Levo is prescribed initially. It is also called T4. T4 is inactive and has to convert to T3 (liothyronine) and it is the 'active' thyroid hormone needed in our T3 receptor cells and brain and heart have the most T3.
My heart was affected with levo only and - especially during the night - and I had awful palpitations but it was resolved when T3 was added to T4.
Starting on too low a dosage of levothyroxine can make you feel worse rather than better. The way it works in situations like yours is that the levothyroxine replaces what’s left of your own thyroid function—but your own thyroid can probably pump out more than 25mcg levothyroxine a day left to its own devices. But 25mcg can be enough to switch off your body’s ability to make its own thyroid hormone. It doesn’t top it up—it doesn’t work like that. So in effect, being on too low a dose is leaving you in a worse place than you were to start with.
Also, if you’ve been hypothyroid for a while, your vitamin and mineral levels are likely to be in a state of deficiency which will probably not be helping things. You quite possibly have low iron, low B12, low folate and low Vit D.
I know it’s hard but you need to keep going. There’s no other way but through. It may sound counter-intuitive but you may find things easier on 50mcg a day—which is the dosage your doctor should have started you on.
Thank you Jazzw for replying it’s all such a minefield and it doesn’t help that I’ve never had a face to face consultation. I just get worried about my heart after reading patient info leaflet and I can’t stop thinking about it. I had an ecg last time and it was ok.
You are not going to have a heart attack on 25mcg of Levo. The thumping heart beat is often caused by not enough thyroid hormone, as Jazzw explained above.
I live with permanent atrial fibrillation, my heart beat is very different to yours. I can have a rate of 120 beats a minute easily and up to 170 beats a minute when walking if I get my dosing wrong. But I'm taking almost pure T3 these days and plenty of it. I'm still here, high heart rate does not equal heart attack.
So keep going. I felt dreadful on 25mcg Levo. You should feel a bit better on 50, at least for a week or two until that becomes too little for you as well. Book a blood test 8-10 weeks after your first pill was consumed and get to speak to a GP as soon as they have the results and request an increase to 50mcg. We have to be proactive. Then 8-10 weeks later repeat the process, and so on until you feel well.
Hi, I be experienced banging heart at night with both too high a dose (which included T3) AND too low a dose. I would try not to worry - and maybe see if you can increase? Your test results indicate that your dose is likely too low. I’ve increased my T4 recently and my resting heart rate has dropped again. First taking T4 can make all sorts of symptoms worse until you titrate up to the dose you need. X
Josephineinamachine when you say your heart rate has dropped after increasing T4 is that a good or bad thing for you? If it has gone too low are you expecting to go up again when you get to the right T4 dose? Mine was already very low before I started Levo and has not risen, in fact dropped, since I started and I am already close to the correct dose for me on TSH metrics (not quite there yet and waiting for T3 result) At night recently it went to 38 bpm. I'm trying to understand if you are coming from the opposite place to me, i.e. that your HR was too high so that going lower with Levo is an improvement
Hi it’s a good thing for me I think. My RHR is now somewhere between 58 and 63 which feels better. It went up to around 75 - 78 when I’ve been both over and under medicated and I felt anxious and also aware of my heart feeling like I was having palpitations. I used to have a RHR of around 50 long before I was diagnosed but was very active and fit then. Not so fit now but still as active as I can be. I think you can feel if it’s right for you either way maybe?
I would definitely follow advice to take 50mcg Levo. Also get ferritin, folate, vit D and Vit B12 levels checked. I too am a worrier…. but I only felt well when my TSH was under 1 & key vitamins high in the range.
Fanakerpan I had bad symptoms for years on levothyroxine. I thought it was the levo so I reduced my dose until I was only taking 25mcg per day instead of 100mcg. I felt great for 3 months and then I became very ill and very hypo. I ended up all but bedridden. In my despair I found this site and learned about thyroid issues.It turns out that the endo had kept me undermedicated all those years which is why I had symptoms. She was happy to keep my TSH at 4 and my FT4 at 15 (10 - 25). But now I know that my TSH should have been around 1 and my other results higher.
Because I now knew about thyroid I became pushy and began to advocate for myself. I was able to get properly medicated.
Learn as much as you can from this site. Become pushy with doctors. Ask for advice here. Accept that medics are poorly trained in thyroid and that you need to be the knowledgeable one.
It be the case that you just don’t get along with that particular brand so try another. I’m ok on mine, but once they swapped in Mercury levothyroxine, and i was ill as within two days! You need your levothyroxine to prevent other serious conditions, like heart disease, so work through your fears. x
I had a similar problem many years ago. To solve it, I started with a very tiny daily dose of about 5mcg - used Levothyroxine oral solution - as you cannot divide a 25mcg pill into 5 equal parts. Then for several months I have been increasing the dose every few weeks by a tiny fraction until I have reached and could tolerate 70-80mcg which was sort of OK for me. I changed then from the oral solution to a pill form, and it was fine.
Hi Margareta3, I wanted to do an update, so my results came back today as "in range" and its likely that once my T4 is in range I start to get the palps and chest pains. I only took it for 1 week this time in order to get in "range" I told my Dr about your situation many years ago and he agreed also for me to have a very small dose of liquid solution and see how we get on, he said he might also have to refer me to an endocrinologist.
Just an update I actually saw a dr today which was so good to get a face to face. He checked my bp listened to my heart and read oxygen, he’s asked me to take one every other day for 2 weeks to see if that resolves it, get a blood test in 2 weeks and then a phone consult, he is testing Bone profile
The info on Initiation and titration says this [Note the bits I've underlined] :
Initiation and titration
The dose of levothyroxine (LT4) should be individualized on the basis of clinical response and thyroid function test (TFT) results. Treatment must be monitored regularly to determine an adequate dose and to avoid both under- and over-treatment.
The NICE clinical guideline recommends:
Consider starting LT4 at a dosage of 1.6 micrograms per kilogram of bodyweight per day (rounded to the nearest 25 micrograms) for adults under 65 years of age with primary hypothyroidism and no history of cardiovascular disease.
Consider starting LT4 at a dosage of 25–50 micrograms per day with titration for adults aged 65 years and over, and adults with a history of cardiovascular disease.
The British National Formulary (BNF) recommends:
For adults aged 18–49 years — initially 50–100 micrograms once daily; adjusted in steps of 25–50 micrograms every 3–4 weeks, adjusted according to response; maintenance 100–200 micrograms once daily.
For adults aged 50 years and over, with cardiovascular disease, or severe hypothyroidism — initially 25 micrograms once daily; adjusted in steps of 25 micrograms every 4 weeks, adjusted according to response; maintenance 50–200 micrograms once daily.
Advise the person to take LT4 medication on an empty stomach in the morning before other food or medication.
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I understand that you are scared of possible adverse effects of Levothyroxine. But have you thought about the long term effects of untreated or under-treated hypothyroidism?
Thank you 🙏 yes I am so worried about not being able to tolerate it, I really want to just be able to take it and feel well, I feel generally fed up that I was fine October to February then I had my first episode of this heart palps chest discomfort which resolved within a few days of stopping taking my meds and now it’s happened again but after just 9 days. Thank you for replying i appreciate all help
Hi Frankerpan. I don't know whether my own experience will help, but I was very hypothyroid when I started levothyroxine last year. In the first few months I found some of my symptoms slowly improved but I also experienced thudding heart beats occasionally which were unpleasant and quite scary. I also felt quite panicky and anxious and my BP would shoot up at the Drs as I developed severe white coat syndrome. I also got occasional bad headaches, the crushing ones.I was unsure if it was the hypo, the levo of even something else. Whenever the Dr suggested increasing my dose ( I started on 50mcg but would need more as the TSH started at 161) I asked to increase slowly as I needed time to adjust. I only very rarely get the thudding heartbeat now and I'm not quite as panicky ( still working on the white coat syndrome), but maybe you are adjusting to the levo. If you've been hypo for quite a while your body will find the levo odd, but given time and careful handling you should adjust and hopefully feel the benefits as you definitely need it looking at your results. I am a different person now compared to the untreated one but I know I will have keep a close eye on managing my condition.
I feel your worries. I was diagnosed with Overt Hypo "TSH 13. something. I was put on Levo 75mcg and it caused severe palpitations. I took another dose the next day and the same thing happened. I took it upon myself to break my Levo in half. I have been on 37.5 mcg for the last 6 weeks. I feel GREAT. I am due a blood test tomorrow. I haven't had palpitations since taking a half dose. Hang in there.
I always wait for the time the pounding heart is more noticeable at night and i just have general sort of chest discomfort it’s so hard to explain 😩 just feel rotten
I've read that too little or too much Levo can cause that. I was prepared to take more if taking less didn't help. In my case, Overt Hypo caused a lot of issues from kidney disease to heart issues. I was Hypo for at least 7 years before my diagnosis. Levo is definitely helping me. Don't stop taking it. You may need to change brands, change the time you take it and change the dosage until you can find what works for you. I'm new to this, but I'm doing what makes me feel better.
You really should not stop and start your treatment. 25 mcg is such a small dose. When I was first put of Synthroid years ago my initial dose was 75 mcg. Have you had these type of issues (loud heart beat at night and internal tremors) before starting to take the levo? I had the loud heart beat when I wasn't dosed correctly (not optimal) so that could be your issue.
Hi there 😊 no, I had it when I was upped to 50 mg so I was sent to get an ecg and stop for 5 days and re start 25. I didn’t do this….. anyway new bloods and I thought I had better start again. I was fine for the first week and then it started up again with loud heart and Adrenalin in chest and let of uncomfortable feeling really, thank you
Hi again Fanakerpan. I had the thudding heart for several months after starting levo. I started in May 21 and I was still having them in Dec 2021 by which time I'd managed to work up from 50 mcg to 75/100 alternate days, so quite a slow progress although my symptoms of hypo were hugely improved .I suppose I'm just trying to say take it slow and trust that it will improve over time, but it may take many weeks or months.
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