Do my test results suggest I'm not converting well?

[Julie2805]

At the end of May I had my annual review and my results were TSH <0.5 (0.4-5.5) outside range free T4 22.4 (11-26) results consistent with over-replacement with thyroxine and free T3 4 (3-6). I had expected my results to show I need an increase in medication as I was so tired but my doctor said it could also be because of overmedication. I thought it was more likely that I wasn't converting well as my free T3 seemed relatively low to say how high my T4 was. She reduced my thyroxine by 25mcg and told me to have another test in 2 months. During that time I started to feel worse than ever and my tiredness was about the same as when I was first diagnosed. I had another test after 2 months and my TSH is was 2.8. From past experience I know this is not a good level for me. Because it was within range T3 and T4 weren't tested (the lab have refused to test it in the past when my doctor specifically requested it and my TSH was in range) so I have no idea if my T3 had dropped even more. My doctor suggested taking the same dose 3 days a week and 25mcg more on the other 4. I did that for 2 months but it hasn't helped and now I feel the worst I've ever felt. I've just had another thyroid test plus the usual ferratin, liver function and glucose tests. The extra tests came back normal but the Thyroid was TSH 0.26, which is outside the range again, and T4 18.3, which is lower than before. The receptionist said they haven't been given anything for T3 but I'll ask my doctor when I see her on Tuesday. I feel like I'm going round in circles and meanwhile I get more and more tired. I nearly fell asleep in a meeting with my boss 2 weeks ago which is more than a bit embarrassing. Does this sound like I'm not converting well? I would welcome any comments/advice, thanks.

[shaws Administrator]

They should not adjust your medication on the TSH result alone. Unfortunately, they think it is the right thing to do with a result similar to yours. Read the first and second questions/answers.

web.archive.org/web/2010103...

This is an excerpt from an article in Pulse Online by Dr Toft of the BTA. If you require a copy of this article email [e-mail].

But some need a higher dose of levothyroxine to suppress serum TSH and then the serum-free T4 concentration will be elevated at around 24-28pmol/l.

This ‘exogenous subclinical hyperthyroidism’ is not dangerous as long as serum T3 is unequivocally normal – that is, serum total around T3 1.7nmol/l (reference range 1.0-2.2nmol/l).

Even while taking the slightly higher dose of levothyroxine a handful of patients continue to complain that a sense of wellbeing has not been restored. A trial of levothyroxine and tri-iodothyronine is not unreasonable. The dose of levothyroxine should be reduced by 50µg daily and tri iodothyronine in a dose of 10µg (half a tablet) daily added.

While taking both hormones it is important serum TSH is normal and not suppressed.

[Julie2805 in reply to shaws]

Thanks, I'll have a read.

[Julie2805 in reply to shaws]

Thanks, I'll have a read.

[shaws Administrator]

They should not adjust your medication on the TSH result alone. Unfortunately, they think it is the right thing to do with a result similar to yours. Read the first and second questions/answers.

web.archive.org/web/2010103...

This is an excerpt from an article in Pulse Online by Dr Toft of the BTA. If you require a copy of this article email [e-mail].

But some need a higher dose of levothyroxine to suppress serum TSH and then the serum-free T4 concentration will be elevated at around 24-28pmol/l.

This ‘exogenous subclinical hyperthyroidism’ is not dangerous as long as serum T3 is unequivocally normal – that is, serum total around T3 1.7nmol/l (reference range 1.0-2.2nmol/l).

Even while taking the slightly higher dose of levothyroxine a handful of patients continue to complain that a sense of wellbeing has not been restored. A trial of levothyroxine and tri-iodothyronine is not unreasonable. The dose of levothyroxine should be reduced by 50µg daily and tri iodothyronine in a dose of 10µg (half a tablet) daily added.

While taking both hormones it is important serum TSH is normal and not suppressed.

[Julie2805]

Thanks. I think I'm one of those who need their T3 to be high. I certainly felt better at last year's annual review when it was 4.8 than this year at 4. Unfortunately I don't think my GP is likely to prescribe anything other than thyroxine.

[Julie2805]

Thanks, if I don't get anywhere with my doctor tomorrow it's something I'm going to have to look into.

[Julie2805]

Well I've just seen my doctor. My T3 had been measured and was 3.8 (range 3-6). My doctor was happy with it but personally I think it's a bit low. I felt much better last year when it was 4.8 but my TSH was <0.05 so my doctor wasn't happy with that. Anyway, it turns out my Ferritin is low. I'm not quite anaemic but heading that way so my doctor has given me tablets for 4 weeks and then I've got to be tested again to see if the levels go up and if they do get tested again after another 4 weeks to see if they stay up. Hopefully it will help with the tiredness and possibly the conversion of T4 to T3 but unfortunately it's a waiting game again.