Which level was 7.5? TSH? Did you have any other thyroid tests at the time? If so, please post results and reference ranges that vary lab to lab and have to come from your own lab report.
How long ago was your RAI?
What were your symptoms of toxicity?
Was hyperthyroid (Hashimoto's), lost a lot of weight had radioactive iodine treatment, weeks later went on synthroid 25 mcg. Just had a "thyroid storm", level was 7.5. Had bad episode of toxicity and ended up in the hospital. Put me on 50 mcg of synthoid and feeling better. Is this common?
I expect that you doctor is off base with that conclusion. Although TSH is a pituitary hormone that is affected by many variables and thereby not a good diagnostic for thyroid, at that level your TSH and your FT4 that is low in the range are good indicators that you are hypothyroid. An even more important indicator is whether you have hypo symptoms or not. Please take a look at this listing of typical hypo symptoms and tell us which ones you have.
http://endocrine-system.emedtv.com/hypothyroidism/hypothyroidism-symptoms-and-signs.html
My tsh level is 7.25 and my free t4 is 0.71. What does this mean? My doctor said it was good.
With a TSH of 7.2, the free t4 will likely be low normal or normal.
What lab performed your tests?
This would indicate "subclinical" or "mild" hypothyroidism. It still deserves to be treated before it progresses further.
Thyroid antibodies would also be a good test to have done.
It would be better for the doctor to get a repeat TSH and free t4 before rx'ing meds.
Synthroid would be the appropriate medication.
What dose did you start on?
Probably.
They need to run a Free T4 test to confirm you need the medication.
A TSH above 5.1 indicates hypothyroidism. It's more complicated than that, but for the moment that answer will do.
They want to give you a drug that will give you additional T4. First they need to know that you are low on T4.
Without a Free T4 test, they are only guessing.
Hopefully they ran a Free T4, and you just haven't mentioned it yet.
They should now be running more tests to find out why you are hypothyroid.
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