unbearable side effects: I want to talk about my... - Thyroid UK

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unbearable side effects

I want to talk about my story here. I find that people here are always the smartest people, people are interested in complicated things, and they think of various ways to solve them, and it is easy. My problem is the unbearable side effects after taking synthetic thyroid drugs. Why I am sure it is caused by the drug because the disabled side effects will be a lot of ease while stop or lower. Later, I changed to Nurture drug, I really feel better, but still exists. Are there any solutions? That side effect is more like the performance of thyrotoxic myopathy: muscle spasms, post-exercise spasms, starting from waking up, because minor movements will trig the muscles vibrating for a long time, and I feel tired all the time, Muscle ache. No matter the level of TSH in blood, the result is no difference, even if the TSH is high, I still have such a problem. I think it is the muscle problems caused by the previous drugs, although the change of medicine, but for such problems, the recovery time will be very long, I should avoid over-exercise, waiting for the gradual recovery. I also have calcium and magnesium supplement, now ready to take L-carnitine. Is some one has had a similar experience?

12 Replies

Hi yizhong, Im afraid your post seems to have slipped through the cracks.

I would repost and include what medication you are taking, what dose and any results you have for TSH, FT4, FT3, TPO, TGAB, folate, b12, vit D and ferritin. If you have a series of results it helps to understand what is going on as doses change and symptoms too. It is important to include the ranges as labs differ and we need them to give you a good interpretation.

There is a lot of cross over of symptoms that occurs with under or over-medication and also nutrient deficiencies. We all react differently and people tend to make assumptions, eg if you are anxious, thin and have tremors you must be over-medicated, but for some the opposite is true.

Muscle and joint issues are more common with under-medication and you mention no improvement even when TSH is high. High is bad, it indicates your body is screaming out for more hormone. Most people will feel better when TSH is 1 or less and when FT4/3 are in the upper part of their ranges. All the nutrients mentioned above tend to be sub-optimal or deficient in hypo sufferers due to the gut function and absorption issues we tend to suffer from snd we iften need to supplement quite heavily. Vit D and B12 deficiencies are well known for causing joint, muscular and pain issues. If they havent been tested they need to be to rule them out as a cause of some of your symptoms if nothing else. It is elimination game to an extent, if nutrients are good then thyroid is next suspect, if hormone levels are good it may be the tablets themselves, I cant tolerate TEVA levo for instance it gave me serious joint issues. Do you always have the same make of thyroid tablet? If you swap about have you noticed that your symptoms change at all, if so you may have an issue with some of the different fillers and binders and need to insist in having the same ones.

I hope some of that helps abd that a repost with more specific details gets you more responses

1 like

Thank Phoenix, it helps. those problems happened since the begin of Levo, where it is very serious that I even do some acceleration movement. The blood test is good except uric acid has a litter high. That happened 3ys ago when I just have the TT and take the medicine. It actually some easy along with the time, but that is far from normal. But I stuck to some sport and leg pain came, felt leg muscle's tendon very hard. gradually, I found my leg strength weak and shrink. I found my cocoon on the footplate disappears which should be there. That means my muscle really have problems. Doctors always have no idea about my situ, it is seldom reported. I had changed brand several times but always felt a little better at begin. after 3yrs, I was found difficult for walking 500 meters. But when switch on Nurture thyroid, things seems improved, I can ride a bike for 20 kilometers although some tiredness. But that has not get a normal one which I should. So I am very anxious that I can not live as usual. A doctor said the myopathic patient should keep quiet without any sports, the recovery time are from 1-3 years. Muscles actually damaged, than a function changes. What is terrible for me will be that Nurture is also the reason. that means I must take it no matter the problem.


Abnormal muscle contraction and tendon reflex are the way that hypo was diagnosed before the tests. Do you always get your full results or does the doctor just say they are fine/normal/ok. Many doctors use these words and are happy that your results are somewhere in the range. As patients we know that it also matters where in the range you are. TSH is a signalling hormone produced by the pituitary to tel the thyroid more hormone is needed, it is not very accurate! If you are on nature throid that is an NDT and contains a good proportion of T3 and also I believe the fewest fillers etc. T3 is what your cells use and why you have more energy than on levo which your body must convert. Most people taking NDT have a very low TSH mine is 0.02, so below range but it does not matter as my FT3 is not over range. TSH is very sensitive to T3 and this tends to freak doctors out, they think we will have a heart attack or get brittle bones, but this will only happen if FT3 is too high.

Levo has caused me serious problems with my muscles especially in my back and neck so I also now take NDT. You need to avoid high impact quick movements until your muscles /thyroid levels improve or you will pop muscle fibres and strain tendons which will take a long time to heal (experience talking). Build up gradually. Exercise uses up a lot of T3, I found if i exercised every day I was fine but if I missed I crashed and had no energy, bear in mind i still have a thyroid so it could compensate a little but you do not, you are reliant on what you put in. You would be better doing a regular amount of exercise every day that way your meds can be set to compensate and you will find your energy levels more constant. T4 is the storage hormone your body converts when T3 is running low, which is one reason why docs like levo which is just T4, the theory is if you do some unexpected exercise etc you have hormone available to convert on demand to replenish the T3. Again with no thyroid and low T4 in NDT you are totally reliant on taking enough T3 day to day so will be better off not piling on sudden demand. You may find that you need to fine tune your dose, if you only do a long ride once a week for instance you may find you do better with an extra quarter or half grain to compensate on those days. You will soon know if you have raised too much as it gives you an unsettled ‘buzzy’ feeling which is not pleasant so just cut back by a quarter at a time until you no longer get that feeling. I really recommend getting all the tests especially FT3 as although there may be muscle damage causing some of the issues and deficiencies contributing to others there are also hints that you may be under medicated.


I may be this feeling of buzzy, will generally be considered overdose, but in fact, I eat very little, 30mg S-thyroid, because too little, I just added to 45, I will eventually add to 60, This dose is more suitable for me. I still feel sudden and sudden fever, but I'm afraid to reduce the dosage


If you are increasing without blood tests the best way is to monitor your heart rate and temperature. They both react to the increased T3 by raising. To minimise sideaffects you could Increase by a quarter tablet at a time and wait for 2 weeks then increase again, this will also avoid you missing the dose where you feel best by going too fast. Being slightly over medicated can feel very similar to under and it is easy to miss that sweet spot where your dose is optimal.

Take your temp on waking every day, if it goes above normal and doesnt even out after a few days drop back by a quarter. When I first started taking NDT i was very hot and sweating a lot but my body temp was actually still low, it was just reacting to the initial boost and soon settled down, I the found this happened for a few days after reach raise but has now settled with my temp being near normal too.

A Normal resting heart rate is considered to be between 60 and 100 beats a minute and I know mine was usually upper 70s low 80s before thyroid issues so if mine drops into the 60s and my temp drops slightly i know i need more. Although my bloods suggest another quarter increase my heart over reacts so I am staying put for now as at the end of the day it is how you feel that really matters (within reason). Some people find they have to go extremely slowly allowing their body plenty of time, sometimes several weeks, to adjust to even very small dose changes with NDT.

I cannot take more than 2 grains at once so I have to split my dose, although you are not on a high dose you may be very sensitive to T3 so splitting the dose may help avoid the buzzy feeling or racing heart. the split doesnt have to be even and can be as far apart as is convenient, some people need to split as many as 4 times but hopefully not, as that is hard to manage properly.


I am suffering from thyrotoxic myopathy due to overmedication. I was on too much Synthroid for over a year (probably didn't need it at all) then very negligent doc added t3 thinking I needed more med when actually needed less. It has been brutal. Extreme weakness, fatigue, neuropathy in feet lower legs (twitching almost constant), fast heart, etc I have totally stopped thyroid med and am on atenolol (beta blocker) I am on 30 day medical leave but doc said could be 6 months to a year! Interesting yours said 1 to 3 years OMG! I am looking for doc to get a second opinion. Did your doc order any tests to show extent of myopathy?


Just a quick note; if that happened to me with TEVA, I would be checking if potato starch was used. I am sensitive to nightshades, of which potato starch is included. It gives me inflammation, which starts generally day after ingestion, including knee and shoulder pain. A thought.


The only ingredient i could find that wasnt in any if the others i had taken was manitol which i have had in other things without any issue. I had a drug allergy many years ago so when mu hands siezed up this time i realised that the joint issues that had been going on was likely due to the TEVA i had been given 2 weeks earlier especially when substantial improvement withinin three days of swapping back to my normal make!


Thank msb, It seems like inflammation. I eat the potatoes every day, I get it.


Have you had your iron levels checked? And B12?


Thanks for mention, iron, B12 checked normal


On Friday night, a miracle happened. Wake up on Saturday morning with almost no muscle shaky. There must be a reason, I feel that the adhesion of the neck muscle release. It seems that all previous symptoms are caused by sympathetic irritation, the surgical process affects the neck of the sympathetic ganglia. If you are interested, I am willing to analyze in detail, if not, I will not on it here.


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