Breathlessness on exertion and rough burning throat

Hi - can anyone help me? I was diagnosed with underactive thyroid a year ago but felt absolutely fine. Doctors put me on thyroxine and ever since then I have terrible breathlessness on exertion and every day have a really rough bad inflamed throat. I have gone on and off the thyroxine because of this and when I go off it I get better and can breathe again but when I go back on it the same thing happens within hours. I used to be really fit, mountaineering and mountain biking, but now I feel like a cripple. The doctors tell me I have to be on thyroxine but it seems to be killing me. I have tried different brands, levothyroxine, tablets and liquid, and also natural thyroxine, Erfa, but they all affect me like this. So now I'm taking nothing but I'm scared as the doctors say I have to take it and it's dangerous not to. Has anyone got the same thing or any ideas of how I can get better?

11 Replies


Can you post recent thyroid results and ranges so we can see whether you are optimally medicated?

Was there any improvement when you tried Erfa? I had a lot of debilitating symptoms, including breathlessness, when I was taking Levothyroxine only but adding Liothyronine (T3) seemed to calm the adverse effects.

Hi - in my last results they just tested for serum free T4 which was 13.4 pmol/L and serum TSH level which was 4.1 mU/L. What I can't understand is why I was fine with no breathing problems before I started to take any thyroxine - I felt perfectly fine and could do a lot of strenuous exercise. Taking thyroxine has caused me to be ill when I wasn't in the first place.

When I started taking Erfa my throat wasn't quite as inflamed although it was still bad, and the breathlessness was just as bad. Maybe, as you suggest, I should tell my endocrinologist to just try me on liothyronine - he did mention that it could be an option.

Thanks very much for your advice in the meantime.


You were undermedicated to have TSH 4.1. I don't know whether increasing dose will make things better or worse.

The goal of Levothyroxine is to restore the patient to euthyroid status. For most patients that will be when TSH is 1.0 or lower with FT4 in the upper range. FT4 needs to be in the upper range in order that sufficient T3 is converted. Read Treatment Options in Email if you would like a copy of the Pulse article to show your GP.

Thanks for your advice - I'm going to ask my endocrinologist to try me on T3 only to see whether it makes a difference or not. What I don't understand is that my throat and breathing was perfect before I even started the thyroxine - I had a TSH reading of 9 - but felt fine and had no symptoms. My doctor just found out I had underactive thyroid in a routine blood test for cholesterol and other things etc. It is only since taking thyroxine that the problems have started so it's like taking extra thyroxine is actually causing all these problems.

Thanks again for your advice, I'll wait and see if just taking the T3 makes any difference.


If your endo won't prescribe T3 write a post asking members to recommend where you can source it without prescription.

I think he will, he said it was an option - thanks

How long did you take Erfa - as it contains all of the hormone a healthy gland would have. I myself had to try several NDTs.

You might have been overdoing exertions when you haven't been on an optimum of thyroid hormones. Thyroid hormones are required to be at an optimum so that we can carry on as 'normal' but when hypo we don't have sufficient particularly doing such strenuous activities as you do/did. Thyroid hormones enable our body to function.

T4 and T3 are thyroid hormones and exercising reduces T3 and it is T3 which is the only Active thyroid hormone required in our receptor cells and to drive our metabolism. Breathless is another clinical symptom and as you have tried different options/doses have you tried T3 only? Sometimes levo doesn't work but T3 alone might or T4/T3.

I shall give you a list of symptoms and tick off the ones you have. In the meantime I'll give you a link about breathlessness.

Do you have blood tests at the very earliest possible, fasting (you can drink water) and allow a gap of 24 hours between your last dose of hormones and the test? This help stops doctor adjusting hormones unnecessarily.

You take thyroid hormones first thing on an empty stomach and wait about an hour before eating.

Hi - I've been taking Erfa for just over three months now but have stopped as I can't handle not being able to breathe properly. I definitely haven't been overdoing any exertions as I get breathless just walking up the stairs and up the road. I haven't been able to do any of the sports I used to. I will ask my endocrinologist to maybe just prescribe me T3 only and see if that makes a difference.

Thanks very much for your advice in the meantime.

I am not medically qualified but I think some of us cannot convert T4 properly into T3 and breathlessness must be quite scary struggling for breath. I hope he at least gives you a trial of T3 for at least 3 months. I tried all variations myself (never had breathlessness) but, finally, I was fortunate T3 removed all my symptoms.

I will definitely ask my endocrinologist to try me on T3 only and see what happens - thanks again for your advice.

Sometimes we have something called 'Thyroid Hormone Resistance' and that can be solved with T3 only (but in large doses). Also Marz has just put up a post which I'll link to as I believe thousands of doctors are unaware of the possibilities that low T3 can cause.

I doubt doctors know that T3 is the only Active thyroid hormone T4 being inactive and has to convert.

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