"Doctor, I have a Sulfa Allergy": Clarifying the Myths of Cross-Reactivity.

Our purpose is to present an evidence-based approach, directed primarily towards eye-care specialists, clarifying whether certain drugs should or should not be used in patients with sulfonamide allergy. We conducted a literature search using PubMed to identify the risk of ophthalmic-specific drugs in patients with a self-reported sulfonamide allergy. MeSH key words included "sulfonamide" and "hypersensitivity". Articles specifically geared towards ophthalmic diseases were sought. The evidence illustrates that individuals with sulfonamide allergy are intrinsically predisposed to higher rates of allergic reaction that is not specific towards sulfonamide non-antimicrobials or sulfur-based medications. We provide a simplified algorithm using the 2017 Clinical Guide to Ophthalmic Drugs to help busy eye care clinicians determine whether a certain common ophthalmic medication is safe or unsafe to prescribe in a patient with a "sulfa allergy".