Abstract: Sodium disulfite, also known as sodium metabisulfite or sodium pyrosulfite, is an inorganic compound, which may cause allergic contact dermatitis. Sulfites act as antioxidants and preservatives; common sources include food/beverages, pharmaceuticals, and personal care products. Importantly, sulfites are not included in most screening patch test series and thus may be missed as a relevant contact allergen. The American Contact Dermatitis Society chose sulfites as the Allergen of the Year for 2024 to raise awareness about this significant allergen.