Other beverages sometimes made from wheat, rye, and
barley include vodka, whiskey, gin and
bourbon. The allergy to alcohol
or to coke even can be due to preservatives, coloring agents, yeast used for brewing, sulfites, gluten products in the alcohol or even to grapes and other bases. You need to go for an allergy testing for the ingredients of the beverage you take to know what you are allergic to. It is difficult to comment beyond this at this stage.