Thyroid UK

Blood results on 50mcg, increase dose to 75mcg

Hi guys,

so after 2 weeks on 25mcg Levo and 4 weeks on 50mcg these are my results:

TSH: 4,9 (range 0,5 - 4,5)

FT4: 15,2 (range 10 - 19)

I don't feel any improvement..Saw my GP yesterday and she agreed to increase my dose to 75mcg and get a blood test in 6 weeks.

Is there a way to calculate how much Levo I will need? Also wondering if you can say on which dose it's more a substitute dose than a bit of help for the thyroid. My results now on 50mcg are a bit disappointing to me..So I'm afraid 75mcg won't be enough either. (GP said I'm still subclinical hypothyroid so treatment is not like anyone who is hypothyroid (as in you don't know if it's the thyroid to blame as my FT4 was always in range. It was low but just in range). Don't agree with that but okay.)

Also wondering if I could feel some improvement soon because I already got 50mcg in my blood or does it still take 4-6 weeks to get it in the cells and work optimal?

18 Replies

has your GP also tested




because without all of them having results over halfway in their ranges you simply cannot utilise the levothyroxine

the above 3 must be corrected before theres any hope of levo working

meanwhile you need T3/liothyronine and not levo


Yes, I'm supplementing for over a year now (multivitamin, vit. D3 and B12) and those are all high in range.

Why would I need T3? FT3 was tested before starting treatment and was in the middle, so I have faith that with the right dose of Levo my T4 and T3 will rise.


but what are your ferritin and folate results ?????????


Last time checked ferritin was 93 (no range) and folate 17,8 (range 7,0 - 25)


need to check ferritin range but if its the up to 150 range 93 is fine

folate is ok too

what about b 12?


I got B12 injections and after that take 2000mcg sublingual tablets. I read that it doesn't make sense to get it tested while supplementing. It was tested after the injections and of course it was really high.


in which case all you can do is keep increasing the levothyroxine by 25mcg every 3 weeks until you loose all your symptoms clear


Flower, we can't guess how much Levothyroxine you will ultimately need. Doesn't matter whether you're subclinically or overtly hypothyroid, a person needs enough Levothyroxine to restore them to euthyroid status ie resolve symptoms. For most, this will mean TSH just above or below 1.0 and FT4 above half way in range, preferably in the top 75%. 75mcg is a replacement dose, not a bit of help for thyroid, but it doesn't mean you won't need more in the future.

You're probably not yet feeling the full impact of the 50mcg dose and it will take 4-6 weeks on 75mcg to feel the full impact of it although you may feel some improvement in 7/10 days as the extra dose is absorbed.

1 like

Thank you so much. So 75mcg is a serious dose if I understand it right. I will have to wait and see I guess, it's frustrating it cost 4-6 weeks after an increase of dose to notice some effects.

I will have patience, it should get better eventually.


Flower, its a PITA waiting weeks to slowly feel better but it's worse to overmedicate which is unpleasant in a different way to being undermedicated. Have a look at the link below which explains how to adjust NDT dose. The principle is the same for Levothyroxine.


That's a really good explanation (the sponge story). I will wait patiently for 6 weeks. My GP also wants to take it slow, that's why I was first on 25mcg, then on 50mcg and now 75mcg. It's for the best I guess.

Thank you.


I like the link Clutter. It's a very good explanation.


Shaws, another member posted it a few months ago. I think it's very good too.


75mcg is not a serious dose it is an average and some need a much higher one to feel an improvement.


I love that link guys, well worth a read and by the way I'm feeling thathankful for the NHS! I would like to tag on a question on to Flower3's post. Should we not be recommending a diet adjustment. Surely we are not relying solely on meds? Are we? :-)


I agree with you. A really important thing I learned and not just with thyroid problems is that it's not just a problem and 1 solution (in this case medication). You will have to help the body in all ways such as supplementing with vitamins + minerals, changing diet so only eat food that the body knows well and can use and a bit of exercise.

I believe we have to support our bodies as best as we can.

To speak for myself, I already was on supplements and diet before starting treatment and still am doing so. I can't do anymore at the moment.

1 like

Hi again Flower

I've been supplementing ready too - interesting to see your story....

I also was prescribed 25mcg to start - although the PIL leaflet says a starting dose of 50 - can't get an appointment 'til on 25mcg for a month - so we'll see - if I was a dog i'd been on at least 200mcg replacement dose! (per weight).

I don't feel any difference really after a fortnight, too early (just got over a cold - hubby had man-flu - always nice when temperature is up!) - not sure whether to say no difference in case she pulls me off Levo, or just say I'm not quite there yet...

What's your docs plan? - to up it 'til you feel better or just 'til the blood tests are 'good'? J :D


My advise would be to stay honest. I understand you, I also was afraid that my GP would want to stop.

But I said that I didn't feel a thing, then she told me my blood results and I said that the combination of not feeling better and my blood result should be enough reason to increase my dose. And she did, haha. I have no idea what the plan is, I take it step by step. I'm glad I'm on a higher dose now and will wait 6 weeks and will see what the next step is. My plan is to keep taking meds and keep an eye on my blood results as it will tell if there is room to increase the dose.

I would say just be honest and say what you want and why. You have the right, it's your body and you want to feel better. Good luck!

1 like

You may also like...