What causes my feet to become swollen whenever i drink alcohol?

Hard to say: without a full history and examining you. Alcohol can cause damage to many organ systems that can explain the development of edema, but it doesn't usually happen JUST when you drink. Liver damage, heart damage and kidney damage can all result in edema. You need to see your health care provider for a complete evaluation, and also look into whether alcohol is causing you OTHER harms as well.