Ok, so after dealing with cholinergic urticaria for over 2 years, trying things from sweat therapy to wearing a sweater, all the time I think I’ve stumbled across why this really happens to me: moisture.
I have come to believe that I developed cholinergic urticaria because of hot, long showers drying out my skin (preventing sufficient moisture). I started taking short, cool/warm showers with instant difference in skin feeling. I also went from using lotion to cream for a thicker coat.
I should also mention that I have dry skin due to eczema but have maintained it well. I hope this helps you all, for I know how irritating cholinergic urticaria can be.