Suggest Cure For Red Blotchy Rash All Over My Chest

Hi, I get red blotchy rash all over my chest, upper arms and sometimes my cheeks..It happens when I get nervous, when I get angry, when I stress about something, when I am exposed to heat or stand in the sun for a short period, and it's the worst when I use alcohol, only one sip and I'm all red. What medication can I use to get rid of it?! It is very embaressing.