So the dermatologist appointment wasn't everything I hoped it would be. He looked at the things on my shoulder and said they weren't anything to worry about, which is good. As for the sweating, he said that there's really nothing that can be done.
He said that my choices are: pills, a strong antiperspirant, or surgery. Surgery is out at this point because I scar so badly and I don't want to do surgery unless it's absolutely necessary. He described the pills as a treatment worse than the disease because they have very bad dry mouth and dry eye side effects. I already have a dry mouth and dry eyes from the lack of estrogen and I don't need more problems here.
He wasn't selling the antiperspirant, either: he said that I would have to do it every day on my abdomen and back and that it would only work for each day. He reluctantly gave me some samples of a gel-based formulation with a 15% concentration of the active ingredient. He said that if I wanted to try using the antiperspirant, the gel would be better than the other, stronger (20%) stuff which is alcohol-based and runnier. At least the strong antiperspirants are available over-the-counter, if I end up using them. I'll try it and see what happens.
Sigh. I went on a shopping spree and bought another bunch of sweaters today. I now have eight or nine sweaters made of acrylic, wool, or cashmere - and not all of them are black. I wore one today and while I was still sweating as much as I usually do, I didn't feel cold or anything. Because I had to take the bus and walk outside I did have to change into a different sweater. If I wasn't going to be outside in the cold, I wouldn't have had to change the sweater.
The waistband of my jeans was still damp but it wasn't as wet as it usually is. So that's something, right? Hopefully all of my new sweaters will work as well as today's did.