My advice would be to seek out a good dermatologist who can, no doubt, explain why you get this rash and possibly give you something for it. It's interesting that this only happens to you when you drink alcohol or get nervous. Please let us know what you find out. There are many of us who would be interested in knowing why.
Peace
Greenlydia
there are loads of people dealing with this, so many people have posted similar stories about their rash. The only thing i can suggest is talk to your doc about betablockers. They helped for me (only temporarily as the doc didn't want me taking them forever) but it's worth a try. mine was called nadalol i think, i only got the rash once in 3 months when i was taking them and i usually get it every day. good luck