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Thyroid UK
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conversion calculation from T4 and T3 to Thiroid NDT

How do I calculate the conversion from T4 and T3 to Thiroid NDT which I would like to try as a next step?

I currently take 100mcg t4 and 50mcg T3. My blood test shows Free T4 at 11.6 pmo/L in a lab with range between 9 and 19, and Free T3 at 4.7 pmo/L in a lab with range between 2.6 and 5.7.

By way of background, I was eventually diagnosed with Hashimoto's by blood test after repeated serious myxedema swelling episodes. I then struggled on the NHS prescribed T4 only with barely improved symptoms of low energy, cold hands and feet, brittle nails, thinning hair, sore joints, irritability.

I discovered T3 about a year ago and the improvement was immediate. That night I was hot for the first time and sweating. My brain fog disappeared as did lack of energy and puffy skin in the mornings where sock marks remain for hours.

I exercise a lot - 5 miles plus running a day and a marathon planned next year.

I am hoping that NDT will be a further improvement. Thanks.

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There is 38mcg T4 and 9mcg T3 in one grain NDT.

Your current dose is roughly equivalent to 3.75 grains NDT. (142.5mcg T4 + 33.75mcg T3).

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