'Sulfur allergy' label is misleading

Abstract

The term 'sulfur allergy' is misleading and dangerous and should not be used. An allergy to a sulfonamide antibiotic may imply cross-reactivity with other sulfonamide antibiotics, but does not imply cross-reactivity with non-antibiotic sulfonamides or other drugs containing sulfhydryl or sulfate groups. Patients who suffer from an allergic reaction to the combination of sulfamethoxazole and trimethoprim should be considered potentially allergic to trimethoprim and/or sulfamethoxazole until proven otherwise, and not recorded simply as 'sulfur allergic'. Allergy to sulfonamides also does not imply cross-reactivity with sulfite preservatives, sulfates or elemental sulfur.