I can't comment on the T3 side of things as I'm just starting to explore that avenue myself, I did however up my Levo from 50 to 100 myself and felt remarkably better for it.
I went to see my GP to let him know I wanted to book another blood test, and let him know I'd changed my own dosage. The message I took from that conversation was as long as they know what they're currently testing for, and know what has been in your system for the past few months, they'll go from there really! It's much better than the alternative, which is you're both on different pages and unsure how you're progressing!
Amanda, your GP is probably concerned about your low FT4. I think you'll have to come clean. FT4 usually drops when adding T3 because T3 stimulates better conversion of T4 to T3. I think you reduced T4 too much, though. 12.5mcg T3 is equivalent to 37.5mcg T4 and you appear to have reduced T4 by 62.5mcg. I'd increase T4 by 25mcg. Ideally you will have a FT3 test before increasing T3.
You need to know free T3 if you are taking T3. GP will be concerned as T4 is low (which is to be expected when you are taking T3). I'd wait and see what s/he suggests before volunteering any information - depends on how much you trust your GP and how clued up s/he is.
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