Thyroid UK
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thyroxine, TSH, free T3 oh it drives me mad!!!

please somone help me to understand all this. my TSH goes up and down, Drs lower and higher my thyroxine. Makes a hell of a difference.

they dont do T3 or free T3 unless forced. What should the Normal, ha, levels of T4 and T3, free T3 and free T4 please.

One of mine the consultant biochemist wrote.. 'significant change to her TSH since last profile? dose change? any signs of over-replacement (unless she is on suppressive T4 for ca thyroid)'

no one spoke to me about this. Nothing. I only know as I asked for the last 10 blood results.

constantly the free t4 is above range and tsh below range and then they reverse.


3 Replies

You don't tell us quite enough to be clear what is happening. But I shall put forward an idea and you can respond.

Maybe you are on 150mcg for a while, your TSH goes down,your FT4 goes up. In fact TSH goes down too far,and FT4 goes up too far.

So they drop the dose to 125mcg. After a while your TSH has gone up, and your FT4 has come down. But the TSH has gone up too far and the FT4 come down too far.

So they increase your dose back to 150... And soon.

If that is what is happening,you could try 125 one day, and 150 the next. That gives you an average of 137 which, hopefully, might be closer to the "right" dose.

The other thing that causes problems like this is if you do not take the tablets well away from food, drink (other than water), supplements and other medicines. Many, many things interfere with how much of the levothyroxine you absorb. It is much easier to get a stable dose if your are taking the tablets a couple of hours away from most other things. Including tea and coffee.


thank you, you have it correct. Trouble is I can not function when they drop my thyroxine. I work with special needs teens and need to be 5 steps in front! I can barely think this morning on 150 a day. Ive been on 175. The gp offered and advised me to go on HRT but wouldnt give me a real reason.

I was concerned about cancer so refused.

I take my pills before food and drink in the morning but only 10mins or so. No one has ever told me to have so much delay in eating before. I will try this in the morning, take them first thing when the alarm goes off. It would still only be 30mins or so before breakfast though. I work full time.

I cant thank you enough for your help.


In which case I strongly suspect that to be a part of the issue.

A number of people here (including me) take their thyroxine at bed-time as this can be better in several ways. But it does not suit everyone. Have a read here:

If you were to change to bed-time dosing, you might need a small dose adjustment as many people seem to absorb better then. Think of maybe 25 mcg - or 25 mcg every other day - change.


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