Thyroid UK
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Predicting your optimum thyroxine (T4) dose

This is interesting - check it out. A study that shows patients with a low Body Mass index ( BMI) of less than 24 tend to get under dosed whereas patients with a high BMI ( i.e. overweight) tend to get overdosed by doctors prescribing T4 or Na Thyroxine. Historically doctors guestimated how much thyroxine to prescribe at 1.6-1.7 micrograms/kg/day and adjusted based on sequential blood results until your blood tests results confimed euthyroidism. This study was based in a patient population following thyroidectomy but I think that if you have been on thyroxine for a long time for Hashimoto;s disease you can pretty well assume that your residual thyroid gland has very little remaining activity.

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My wonderful dog is dosed according to her weight :-)


Really? Mine isn't. He was given his first dose according to his T4 blood test.

maggiesloper I think that's the way they do it when you have a thyroidectomy. But, otherwise, they just start you low, and - with a bit of luck - increase slowly until the symptoms disappear. Well, that's the way it's supposed to be, but in reality, doctors just increase until your TSH is somewhere in range, and think you should then be fine! I say, you need what you need, and that's what you should be given. :)


Yes blood T4 levels is the way they do it, but this article is aimed at predicting a dose more accurately so optimal levels can be achieved much quicker and reduce the time you have to waste feeling bad until the correct dose is found. Remember that dose adjustments take up to a month to work properly


Actually, they take six weeks. And this method isn't going to make that any shorter. It just doesn't work that way. You always have to work yourway up slowly, and yyou'll know the right dose when you get there. There aren't any short cuts possible.

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