Help with T4/T3 dosage please.: Hi, A couple of... - Thyroid UK

Thyroid UK

136,965 members160,561 posts

Help with T4/T3 dosage please.

TJM3 profile image
TJM3
15 Replies

Hi,

A couple of years ago I was taking 75mcg T4 given to me by my GP, but wasn't brilliant

and changed to T4/T3 combo as suggested by a private Dr. I've felt a bit better

with the added T3 and my fibo is not quite as bad, but I'm so tired. My Dr. thinks it's my adrenals,

but I'm not convinced, I have everything I'm supposed to and my pressures are now pretty

good at the moment. I'm only taking 37.5mcg T4 and 12.5mcg T3 one day and 31.25mcg T4 and

12.5mcg the next day. Last year when I had my blood test done my FT4 was 9.8 range 12-22

and my FT3 was 4.1 range 3.1-6.8 when I was taking 37.5mcg T4 and 12.5mcg T3 daily. When I was on 75mcg T4 only it was FT4 19.7 and FT3 4.6. So it looks like I was better on T4 only.

I don't know whether I should increase my T4 to 50mcg and 12.mcg T3 everyday as it's a low dose

that I'm on, or do I go back to T4 only. I don't know what to do, any help would be really

appreciated please.

Thank you,

TJM3

Written by
TJM3 profile image
TJM3
To view profiles and participate in discussions please or .
Read more about...
15 Replies
Aurealis profile image
Aurealis

What dose did you feel best on? I'd try to adjust until you feel well, keep it stable then have a test to see what you've adjusted to. The objective is to improve how you feel not improve test results- that's the mistake many GP s make. Tiredness can result from too high a dose or from too low a dose, so not helpful with regards to dose adjustment. You could try taking your temperature, heart rate and blood pressure as these can be helpful as an objective measure of how your body is responding to your dose.

TJM3 profile image
TJM3 in reply to Aurealis

Hi Aurealis,

Well last year I didn't feel this tired and I was taking 37.5 T4 and 12.5 T3, but

still wasn't that great. My temperature is averaging out at 36.2 in the morning and pulse is 69, in the afternoon it can go into the low 80's. My pressure is normally on the lower side until I have my Nutri Adrenals. I don't know whether to increase the T4 or T3.

Thanks for your help.

Aurealis profile image
Aurealis in reply to TJM3

It's tricky when you have both to adjust. Perhaps increase T4 so you're taking the same every day then see how you feel. Then try a small increase in T3 and see how you feel. I'd take measurements first thing each day and immediately before each dose of meds and a couple of hours later and see if there are any useful patterns to help you to work out what to do as you change doses. I'd avoid changing both at the same time, as it gives me a very unpleasant feeling of disorientation. You could also try redistributing T3 within the day, this can have more effect than you might expect (and continue measurements). Your dose does seem small, but we are all different. Your pulse and temperature do not suggest that you necessarily have to make a big adjustment - trust your instinct, making small changes will hopefully give you more clues and then you'll know what to do.

TJM3 profile image
TJM3 in reply to Aurealis

Thank you, it is tricky. I'm nervous about T3 because when I started on it I got very jittery. But I think I'll just have to try and make small increases and keep a close eye after the T4 incease.

Jazzw profile image
Jazzw

You're not on enough of either, I suspect. You're on tiddly amounts of T4 and T3 - I'm utterly puzzled by the fact you're alternating between 31 and 37mcg of Levo - such a tiny change each day would make virtually no difference to your treatment. What I think your private endo should have done was to leave you on 75mcg of Levo and add 12.5mcg of T3 to that. I'm not surprised you feel tired - you're on child-sized amounts of medication.

TJM3 profile image
TJM3 in reply to Jazzw

Thanks Jazzw, I've thought for a while I wasn't on enough, when I see others who are on quite large amounts. I did wonder about going back on the 75mcg T4 and adding a little bit of T3, but it's so difficult to know what to do.

shaws profile image
shawsAdministrator

Your dose is extremely small and blood tests don't tell a story - it is how the patient feels that's the most important. You are taking the equivalent of about 80mcg of levo which as mentioned already is quite small.

If I were you I'd take 25mcg of T3 = approx 100mcg and take your 30mcg dose of T4. If you are nervous of increasing your dose, gradually every week increase T3 by 1/4 (6.5). I take T3 alone and feel great.

Before the blood tests were introduced the average dose of NDT (that's all that was available) was between 200mcg and 400mcg daily.

TJM3 profile image
TJM3 in reply to shaws

Hi shaws,

Thank you, that also sounds like a good idea, I think the T3 does make a difference. I thought we should try and keep the T4 and T3 at the same ratio as our bodies, but that's really not that possible, unless you take NDT, which I have tried, but didn't get on very well with it. I suppose it's a case of just try it and see, but my Dr seems to think I should stay as I am, but I can't keep feeling this tired, I can't get on with life at the moment.

Clutter profile image
Clutter

TJM3, The T3 has probably suppressed your FT4, it happens quite a lot. If you have enough Levothyroxine I'd increase by 25mcg to 62.5mcg. Your FT3 is quite low so I don't think there's any danger of overmedicating.

TJM3 profile image
TJM3 in reply to Clutter

Hi Clutter,

Thanks, I didn't know that about the T3 suppressing the T4. I know they say they should both be in the upper reference range to be well, but the only time my T4 was up there was when I was on T4 only and my T3 was slightly higher than it has ever been since taking T3. It's so confusing.

greygoose profile image
greygoose in reply to TJM3

No, not confusing, normal. :)

When you are taking any amount of T3, the body stores less T4 for conversion, because it's getting ready-made T3. Having both T4 and T3 at the high end of the range only happens when you are on T4 only.

But quickly looking at your results when you were on T4 only, it would appear that you weren't converting very well. Therefore, you are better off taking some T3 rather than T4 only. It's just that you aren't taking enough.

Clutter profile image
Clutter in reply to greygoose

GG, Apart from less need for T4 storage I think taking T3 may stimulate better T4 to T3 conversion which will 'use' and deplete T4 levels too.

greygoose profile image
greygoose in reply to Clutter

May and may not. Didn't do it for me.

TJM3 profile image
TJM3 in reply to greygoose

Thank you greygoose, you've explained it very well. I'm going to add some more T3 I think. :-)

greygoose profile image
greygoose in reply to TJM3

:)

You may also like...

Help with T4 & T3 dosages

guidance. My Endo is pretty much useless when I need her help and I'm so sick of hearing her say...

Help with t3 + t4 dosages

I am just about to start taking t3 a well as t4, but don't really trust my doctor who does not seem...

Help please with t3/t4 combination

suspected it's better... I want to try Levo and t3 combination. The only problem is that when I try...

Change of T4/T3 dosage?

results. TSH 0.01 ( 0.27-4.2) FT3 7.5 ( 3.1 - 6.8) FT4 14.8 (12.0 -...

Combi T3 and T4 dosage suggestions

(74Levo+21Lio) and I was feeling great up to when they take off market. I did a combi for one year...