I have CRPS type II on my right side from a venipuncture nerve injury 8 years ago to my right arm. My symptoms are worsened under cool or cold conditions, and my right hand often gets cold when I'm on the computer for long periods in a cool room.

One thing that helps me in situations where I need to warm up that arm/hand is to put a ThermaCare heat wrap thingy on my forearm just below the elbow. They react to air when opened and generate a lot of heat for about 8-10 hours. I usually have a stash of the arm/neck ones, which come in red boxes, and cost about $2 each (box of three for ~$6). I use a couple of them each week during the winter. They increase my overall body temp as well, not just my arm. I've never had a rash from the adhesive. Good product.

I've even used them with our boy scouts when they are camping outside in winter. I give them a few hand warmers to put in their pockets, then give them one of these to stick on their body somewhere to keep them warmer overnight.

Good luck!

Annie