Dear Amanda- I appreciate you sharing information about GD, but the information you provided concurs with most the information provided about GD and although it was written in 2010 it is the same standard outdated information which isn't helpful for most. You suggestion that sweat and heat I agree with as it does seem to make it worse and the very least it does feel worse. but then again that only addresses the symptoms and not the underlying cause. I also wonder at the standard fact given that more men have it then women is confusing as the majority of bloggers on this site and others with GD are women, yet that could be because women will discuss it. I question if the research on which sex is more likely to have GD is outdated. Today's woman may spend just as many hours in the sun as men and there does seem to be a pattern of those with GD being "outside" people. The problem with it is that for those of us blogging on this site and other sites I read the treatments offered in this Mayo information offer no relief. They offer no ideas as to the cause, yes I do believe sun damage is part of it but new information has come about which may eliminate part of the cause and I will explain that later in this message.
In all my years of blogging only a handful report any relief from steroids, a treatment recommended. Personally, although they helped me with Allergic Contact Dermatitis, ACD, symptoms, topical steroids provided no help with GD. Also I tried cortico-steroid injections which would help with my ACD but did nothing for GD relief or remission. I think doctors are trying to treat all eczema equal. They don't try to treat all types of cancer equally.
Some have talked about light therapy and I tried exposing my skin to brief periods of sunlight and the problem is when GD is active sunlight or heat of any kind hurts and I found heat from sunlight or heat from other sources made it worse, just as you mentioned.
I believe the Mayo site needs to be updated. It's a fact that for me and about 50% of us doing a heavy metal detox with fresh or frozen cilantro smoothies daily finally put our GD into remission. Please re-read the GD blog from Feb 2019, the Feb 27 post by kimass1 recommending cilantro changed my life. I wrote up my success with cilantro and that of others on this site and gave it to both of my dermatologists and neither seemed interested in the concept of a heavy metal detox, a natural chelation by drinking fresh or frozen cilantro daily for a few months. At the very least doctors should recommend this as I don't believe any harm can come from trying a natural chelation for a few months. Yes one can get their blood chelated to remove heavy metals with an IV putting in the drug or pill forms, but this home remedy does the same thing without the need of a hospital, lab or doctor.
Why do you think doctors are so reluctant to explore alternative ideas when the old school treatments they keep suggesting aren't giving any relief. .

Thank you Amanda for the information you sent. I appreciate any and all information you share.