Mine started within the first month after rai when i became hypo–the itching especially while taking a hot bath caused me to run a TSH which was 9.0. that’s when the doc put me on synthroid. the itching ended and that summer i really noticed the yucky skin. I’ve been to several doctors since and they pretty much say, “oh wow, yeah that’s pre-tibial myxedema, and it doesn’t develop until AFTER you’re treated for graves,”
by which they probably mean, when rendered hypothyroid. None of the docs including a dermatologist i saw for another matter offered any suggestions for treatment. They seemed more curious or fascinated then concerned.