are sulfa drugs and sulfites related
Sulfa is short for sulfonomides which is a kind of antibiotic. Sulfonomides are not chemically related to sulpher or sulpher salts i.e. sulfates, sulfites-these dont not cause the same allergic reaction that you see with sulfonomide antibiotics. You should be careful with both kinds of drugs however as you can be allergic to both as I am. I get the same allergic reaction to both. Allergy to sulfa drugs is a popular term for related medications. Once allergic: sulfites, nickel and even tea laurel sulfate (found in soaps, shampoos, etc.), can cause irritation or an allergic response.