Food additives are natural or synthetic substances added to foods at any stage of production to enhance flavor, texture, appearance, preservation, safety, or other qualities. Common categories include preservatives and antimicrobials, colorings and dyes, flavorings, antioxidants, stabilizers, and emulsifiers. Natural substances rather than synthetics are more likely to cause hypersensitivity. Although rare, food additive hypersensitivity should be suspected in patients with immunoglobulin E (IgE)-mediated reactions to multiple, unrelated foods, especially if the foods are prepared outside of the home or when using commercial products. A complete and thorough history is vital. Skin prick testing and/or specific IgE blood testing to food additives, if available, additive avoidance diets, and blind oral challenges can help establish the diagnosis. Once an allergy to a food additive is confirmed, management involves avoidance and, if necessary, carrying self-injectable epinephrine.