Levo making T4 increase - confused: Hi all I got... - Thyroid UK

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Levo making T4 increase - confused


Hi all

I got diagnosed with Hypo and hashis when trying to get pregnant for 2 years.

Despite having my thyroid checked (and my TSH level being over 5) - the GP didn't mention this could be a problem so i only found out when I went for an IVF consultation and they said i needed to get it down to 2.5 or lower.

At that point my TSH was 5.27 and I went on 25mcg of levo for 6 weeks. My TSH then came down to 3.8 so they increased me to 50mcg and my TSH went back up to 4.4. they then suggested 75mcg and after 2 weeks of taking this i felt awful - exhausted, dry skin, weight gain, felt really blue etc. My doctor couldn't explain why this had happened and told me to go back to 50mcg and to see an Endo.

The endo tested my T3 (which my GP wouldn't do) and it was 3.7 with my T4 at 15.4 and my TSH at 3.19 - does this seem ok?

I asked him to prescribe me T3 as i'd read good things about it when people react badly to levo, which reluctantly he did so I am now taking 50mcg of Levo and 10mcg of Lyro.

I've only been on this for about 2 weeks and at some points i feel noticeably more alert and other time noticeably more tired!

Does anyone think I should be doing something else or had a similar situation?

Thanks in advance!

10 Replies

'The endo tested my T3 (which my GP wouldn't do) and it was 3.7 with my T4 at 15.4 and my TSH at 3.19 - does this seem ok?'

It would be helpful if you added the ranges for the FT4 and FT3, but even without them, no, it's not ok at all!

With a TSH of 3.19, you are still hypo and under-medicated. So, you needed something more than 50 mcg. Great that your endo agreed to T3, because it doesn't look like you're converting very well. If the ranges are the same as those we usually see, your FT4 would be mid-range, and your FT3, right at the bottom of the range, which indicates inadequate conversion.

However, I'm not a doctor, but it seems to me that your endo should have started you on 5 mcg T3, and increased to 10 after a couple of weeks. If you're not used to T3, it can be a bit stressful to the body to suddenly start on 10 mcg. So, if you're feeling it's a bit much for you, you could lower your dose to 5 for a couple of weeks, and then got back up to 10 when you're ready. When is your next test scheduled? Don't forget to leave 12 hours between your last dose of T3 and the test. Any more and you will get a false low, but any less than 12 hours will give you a false high, and you don't want that! :)

mb82 in reply to greygoose

Thanks so much for replying!

I thought the ranges that they put on the results just show the 'normal' range so are standard - am I wrong?

Here they are, this was BEFORE he gave me 10mcg of T3 and after I had been on varying levels of Levo for about 20 weeks.

TSH 3.19 ( 0.27-4.20 ) mU/L

Free T4 15.4 ( 12.0-22.0 ) pmol/L


T3 3.7 ( 3.1- 6.8 ) pmol/L

I certainly feel better now than I did when I went up to 75mcg of pure levo, but I haven't felt 'wow' like people say they feel when their levels are right.....

I've ordered a test kit online - good to know i should do it 12 hours after T3 - no doctor tells you that!

greygoose in reply to mb82

There's nothing to say that your levels are right. But, I have to admit, I've been on T4 only, T4+T3, NDT, and T3 only, all at varying doses, and have never once felt 'wow'! I think there are just some people that never feel that. But, I have to say, I feel much better on T3 only, than I ever did on any form, or any amount, of T4.

Having said that, 75 mcg levo is not much more than a starter dose. So, you were probably grossly under-medicated on levo. Doctors just don't understand about the difference between 'in range' and 'optimal'.

The so-called 'normal' ranges are fixed by the lab that does the tests, and therefore varies from lab to lab. Some of them do use a common range, but you can't count on it, so we always need to see the range to be able to interpret the result. :)

mb82 in reply to greygoose

So do you think it was a mistake to stop 75 levo and go back to 50? I just felt so awful - knackered, really emotional and also dry skin, weight gain etc.

If you were me, when would you take your next test? How long should i be on the T3 before I test again?

I am aiming for TSH 2.5 but do you think even that should be lower?

Maybe I should try taking 75 levo with my T3?

It's all so confusing - thank you for helping me to clear it up!

greygoose in reply to mb82

Yes, it is confusing - even for doctors, it seems! But, it's all trial and error. We won't know what is best for us until we've tried it.

I can't answer your question about going back to 50 from 75. If it made you feel better, then it was the right decision. If it made you feel worse, then it was wrong. That's all anybody can say. It's as much about how you feel as it is blood tests.

I would leave testing for at least two weeks after starting the 10 mcg - if you want to try going lower, as I suggested, then two weeks after you go back up to 10. But, you only need the FT3 tested. Beware of doctors that will only test the TSH when you are taking T3! The TSH will tell you nothing.

As I said, it's all a question of trial and error. I don't think you should increase your levo to 75 mcg, I can't see the point if you're not very good at converting it. But, I could be wrong. For the time being, stay on 50, and see how you go by slowly increasing the T3.

gabkad in reply to mb82

You should be aiming for a TSH of 1.0 +/- 0.4. Not 2.5.

When you start taking T4, your pituitary slows down and whatever your own thyroid was producing also slows down. It's a negative feedback loop. You got caught in that when you increased the dose to 75 mcg T4.

You'll find out how your Ft3 is with the T3 and you should see a concomitant reduction in your TSH level. fT3 should be very close to 5.0 or slightly over if you get blood taken 12 hours after your last dose of T3.

Also, ask to have your B12, D3, folate, ferritin and vitamin A level checked next time they check your thyroid business. Being hypothyroid means nutrients are poorly absorbed from the digestive tract and if you want to have a baby, you really must make sure these other things are at good levels. Inadequate folate and B12 result not only in spina bifida but also septal defects in the heart, and probably cleft lip.

mb82 in reply to gabkad

Thanks I'll request those tests. So are you saying if you feel unwell on a new dose of t4 you should just push through as it's likely you could feel worse to start with and then eventually feel better?

Is there any reason why pure t4 would be better than the combo of t4 and t3 that I'm on?

Better? No reason at all except that T4 is cheaper than T3 in the UK. A combination of T4 and T3 or T3 alone is more effective for most people, especially if they are poor converters - and the success of your pregnancy is at stake here.

Thanks so much. I'll stick to 10 of T3 and 50 of Levo for now and test in a couple of weeks (then I have given myself 4 weeks on that combo) - I'll do the test through the online place where they test for everything - fingers crossed!

gabkad in reply to mb82

It takes longer than 2 weeks for the TSH to respond. That's why 6 to 8 weeks is the recommended time interval for testing after dose is changed.

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