Did they do a thyroid panel? If not, that is what you need to have done. I have never really heard of a rash with thyroid, but I have come to learn anything is possible with this disease. You need to suggest, because they dont think of it themselves, to your doctor to check his thyroid.
That's good advice from Christine01. You don't see hives mentioned on very many medical sites but high level thyroid antibodies can cause the. The reson I searched about this is because I came down with severe hives just before being diagnosed with Hashimoto's Disease and did not make the connection until two years later, when I found mention of it happening with Hashi's. I had NEVER had hives before and not since but they are always an immune system reaction (allergies or antibodies) or in response to tremendous stress. I agree that they should run thyroid panel blood tests for your son and keep blood testing any areas of suspicion until an answer is found. My "Eos"(eosinophils)were also flagged "high" when blood testing to find my Hashi's thyroid disorder.
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