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Thyroid UK
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hi everyone can somebody give me some of their experiences there side effects with this medication are you gaining weight are you losing weight how's your memory I'm not overweight but the weight fluctuate I'll lose 5 I'll gain 5 I'll lose 5 I'll gain 5 and I really don't have a appetite I've been on it for 3 months now 100 mcg

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Denabennett, 3 months is early days so you may not be optimally medicated yet. If you can post recent thyroid results with the lab ref ranges we can advise.

I lost my appetite and 7kg I didn't need, or want, to lose soon after starting Levothyroxine (T4) although I'd previously been fine on Liothyronine (T3). I gained 2.5kg weight when I stopped taking T4 on 2 occasions but it dropped off as soon as I resumed T4. Memory was poor and I was quite brain fogged but that was probably because my FT3 was below range and both improved within days of adding T3 to T4.

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Hello Denabennett

Welcome to our forum and sorry to hear you are having problems.

Weight issues and memory problems can easily be caused by unbalanced hormones. It is difficult for members to comment without thyroid hormone test results. You will need to post these in a new question complete with ranges (numbers in brackets).

Remember to always take your pill on an empty stomach, 1 hour away from food , 2 hours away from supplements and 4 hours away from calcium and iron.


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Hi I'm on this. My memory is terrible! Have been blaming it on the menopause but now wondering if it's my thyroid. My weight is not great,could do with loosing a stone. I'm 55. Good luck


Hi, I have noticed my memory isnt what it used to be, also I am really struggling to lose weight . At the moment I am following a calorie controlled diet of 1200 calories a day but nothing seems to work , very frustrating. Mood swings but then I have always been prone to that ha ha . the tinnitus is the worst thing though.


I was diagnosed nearly 3 years ago now , I'm on 75 me of levothyroxine daily and have gone from 8.5 stone to 13.5 stone my whole life I have never been able to gain not even 1 lb I'm constantly getting my levels checked as I'm still always tired and not able to do much because of my weight one doctor says I should be back to normal by now and sends me for tests another says it's a side effect of having this condition I don't know if my story helps in anyway but I hope it does , take care x

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Ive been on 250mcg of levo for 9 years now and im still tired ive gained 6 stone memory is shocking and still feeling low it does nothing to relieve the symptoms of not having a thyroid for me i wish u luck with it x

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Hi, I've been on various levels for the past 8 years. It was increased last year to 250mg daily (due to pregnancy). I've never noticed any difference when I take it/don't take it, and when I finished breast feeding, I stopped taking it altogether. After 4 months of NOT taking it, and noticing no difference, I went to the gp and asked if a full test could be done as a baseline. When the results came back, I was put back onto 100mg daily, to be checked after 2 months. The only difference I've noticed is that my migraines have returned - none during pregnancy, or while NOT taking Levo, but 3 in the past 6 weeks.



Hi, I've been on Levothyroxine for about 20 years. It took me several years to lose the weight that I had gained over the previous 4 years of being undiagnosed ( I kept being told I had thyroid symptoms but was in the normal range ) I gained almost 4 stone.

I have now lost the weight and a little more besides. I only have one problem with levothyroxine - my blood sugar level suddenly plummets. I get really unwell - head ache, tingling, bad temper. This means that I have to eat every three to four hours. I don't have to eat much, but I really have to eat. This makes it impossible for me to lose weight through dieting. It just does not work as I become so unwell as soon as I cut down on food. When travelling, I always pack loads of sandwiches just in case of delays!!

I have always eaten healthy food and don't like fried, fatty foods so I can't change what I eat only the amount I eat. I lost my weight and keep it off by exercising. I bought an exercise bike and do at least 30 minutes, 6 mornings a week. Luckily taking levothyroxine gave me the energy to do this.

I hope this helps.


This is not a side effect or issue with levo..you are undermedicated. Hypothyroidism can cause low blood sugar and eventually high blood sugar, insulin resistance and type 2.

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I do not believe that I am under medicated. All other signs that I have point to me being over medicated - I am always warm and tend to perspire easily. Really would not want to be on more levo. This has been a consistent symptom/problem/issue with me. Over the years my dose has varied both up and down from 100mg a day and each time following blood tests it was put back to 100mg which I've been on continuously for the last 12 years or so.

My blood test results ( which I don't have much faith in! ) are all ok except for tsh which is a problem with being on liothyronine.


Why is your TSH a problem? And what do you mean by 'ok'?

Your thyroid is your thermostat. When your thyroid starts to fail, you can no-longer regulate your temperature. You could end up continuously cold, or continuously hot, or swing from one extreme to the other.

It's a mistake to think that hot is hyper and cold is hypo - either could be either. Just like blood pressure and weight, you can't say that one is this and the other is that. Symptoms cross over and hypo's can be thing with high blood pressure and hypers can be fat with low blood pressure. Just no telling taking one symptom out of context. It's the accumulation of symptoms that gives us a clue.

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I agree with greygoose and might further add that having your meds regulated based on TSH is not accurate. Many other doc's at least test a free t4..you are undermedicated and symptomatic. I had horrible hot spells and sweating until my meds were raised.


Hi, Thank you so much for taking the time to reply.

My GP has been trying to get me to reduce my liothyronine from 3 x 20mg tabs a day for the past 7 years - 4 months after I was put up from 1 tab a day.

She gave me the choice of reducing liothyronine back to 1 tab a day or reducing levothyroxine from 100mg a day to 75mg a day. This did not make sense and I refused. I've continued to refuse to reduce either of them. I have been moved on through two further Gps at my local practice due to my refusal.

I was unwell for three months over Xmas. I thought I could be over medicated and agreed to reduce liothyronine by one tab every third day. I was much worse for the next three weeks and put myself back up. Then I discovered there had been problems with three of the batches of liothyronine that I had been taking.

My results: 31/12/14 - T4 11.7, T3 6.27, TSH < 0.01

14/2/15 - T4 15.2, TSH <0.01.

My surgery refuses to give me the correct ranges for any of these - I have to go to a results telephone line and person there does not know!!

My T4 increased from 11.7 to 15.2 in 6 weeks , can anyone tell me what this means?

The Gps are concerned that my TSH has been suppressed for at least 7 years and I should reduce liothyronine, but even being really ill and having a problem with liothyronine, did not change my TSH.

I've been dependent on food every three hours for as far back as I can remember. Likewise I run on warm.

I also have always been prone to head aches, now I always seem to have a head ache and my memory has got really bad lately.

Initially 17 years ago, I was put on levothyroxine experimentally after suffering loads of hypo symptoms for 4 years and still having blood results in the "normal" range. It seems to me that I need more T4 and T3 than is shown in "normal" ranges. The problem is, how do I get a Gp to agree to increasing my levothyroxine?

I know I can ask to be referred to a consultant, but how do I find a good one? 7 years ago, I went to Nottingham and saw a very helpful man. I returned 4 months later for a "routine follow up", saw a different guy, and was told to go back to what I had been on prior to my previous visit. It doesn't inspire confidence especially when I had been so much better on the new regime.

Any advice or help is really appreciated.


Dizzy864, FT3 6.27 is probably top of range but I doubt is over. Ring the pathology lab at the hospital which analyses your bloods and see whether they will give you the ranges.

No idea why FT4 would shoot up suddenly. Might be an idea to check FT3 is still within range. You can order private tests from Blue Horizon and Genova via thyroiduk.org.uk/tuk/testin...

Some people have suppressed TSH on 75mcg Levothyroxine only. 20mcg T3 + 75mcg T4 is enough to suppress TSH in most people.

This link may be helpful tiredthyroid.com/tsh.html

Galathea is another member who needs to eat every 3/4 hours or becomes unwell.


Hi, Thanks for your reply. I did ask my gp surgery which lab they use. Apparently, they use several different ones - I suppose the cost varies! They said they were not able to give me specific info on where they send it.

My surgery has always been reluctant to give out results or info about results.

I am not able to change to a different surgery as I live in a village and this is the only practice that will take residents from here.


Dizzy, you can buy your entire manual and electronic GP records for £50, the ref ranges should be on your test results.

Alternatively make a formal subject access request to the practice manager to get the lab ref ranges.




Thanks for your reply. I've got an appointment with a GP on Monday to discuss my problems.


Do you have Hashi's, Dizzy? That could account for the rise in FT4.

I'm not sure you want your levo raised, it would be better, perhaps to raise your T3. If you Don't convert very well, you're not going to be able to do anything with extra T4.

Good for you for refusing to drop your dose!


Hi Thanks for your reply.

No I don't have Hashi's as far as I know.

I saw a new doctor this morning. My blood pressure was raised and my pulse was quite fast - never had either problem before. Initially, she gave me choice of reducing levo OR Lio. I absolutely refused and said I wanted levo increased from 100 to 125mg.

She agreed to do this on a 28 day trial if in return I agree to have an immediate blood test - for thyroid and diabetes ( never had that tested before ) and that I agree to a referral to a consultant after the 28 day trial.

I agreed. I had the blood test this morning ( very lucky I got an immediate cancellation!) and start the increase levo

this evening.

I am a little worried as it was my birthday last friday I had carrot cake on Friday, Saturday and Sunday - I never normally eat cake but two sons treated me to some home baking. I hope this won't give a false reading for diabetes.


I Don't think the carrot cake will hurt. As long as you didn't eat it just before the test!

You haven't got Hashi's as far as you know? Does that mean you haven't been tested? Ask the consultant to test it when you see him. It's best to know.


Hi, Thanks for your reply. As far as I know I have never been tested for Hashi s. What exactly is it? What are they signs / symptoms?


Hashi's is an autoimmune disease that slowly destroys your thyroid. Symptoms can be anything, but as your gland gets smaller and smaller, and can make less and less hormone, you will get more and more hypo.

The point is, if you know you have it, you can take steps to help yourself. You could go gluten-free and see if that lowers the antibodies. You also need to keep your TSH suppressed. And others will be able to tell you things they did to ease their Hashi's.

There's no cure, of course, which is why doctors Don't test if they can help it. They Don't know what to do with antibodies - and some even think it doesn't make any difference. But it does. It can explain things that are otherwise inexplainable - like the way your FT4 went up suddenly.

There are two antibodies to test : TPOab and Tgab. You need both to rule it out. Doctors will say only one is necessary, but once again, they are wrong. So sad.


Hi...I've been taking 200 mcg levo with 15 mcg t3 and my memory has never been worse. I gave up midwifery because of it. I've also never been heavier ...so after 6 years I've never been more miserable :(


Well, 200 is a hefty dose, and 15 t3 is miniscule. And if you're not converting that 200, it'll be rattling round in your blood, causing problems, while you're trying to survive in a tiny amount of T3. And it sounds to me as if your FT3 is rather low. Have you had it tested? If not, try and get it tested, along with the FT4, and we'll be able to see a bit what your body is doing with that hormone.

It's not just about what you're taking, but how your body handles it.


Hi Greygoose...No i dont convert well....my last ft4 and ft3 were both midrange on 15mcg and 200 levo, however i have just reduced the levo as feeling toxic. I struggle to raise t3 as my heart goes mental hence the beta blockers. When i was taking t3 only both TSH, ft3 and 4 were virtually nil which caused my endo concern. I have decided to start again. Im going to order a full set of bloods and adrenal saliva test etc , vits/minerals and an iron panel. Then im going to start addressing each issue and start NDT at some point too. pahhhhhhhhhh! Kill or cure...eh?xx


Endos can't seem to get the fact that when your taking T3 only, the TSH and FT4 are going to be very low - and it doesn't matter! But if your FT3 was too low, then you weren't on a high enough dose.

But instead of prescribing you beta blockers, he might have been better off investigating your cortisol and seeing if you had any nutritional deficiencies, rather than leaving you to do it for yourself. You could be low on magnesium, which would affect your heart. Their motto seems to be : why bother with the root of the problem when you can prescribe a dangerous drug! Ah well... Good job you're intelligent! lol


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