I am allergic to sulfa drugs. how likely is it that i'm also allergic to the sulfites in red wine?

Sulfa not= sulfite: Sulfonamide drug allergies are not generally predictive of reactions to sulfites. Although they sound similar, the body sees these chemicals quite differently. Sulfa antibiotics easily stimulate the immune system to make specific responses, hence allergies, but most reactions to sulfites are due to it being broken down into sulfur dioxide gas inside the body.