Management of Polyethylene Glycol (PEG) Allergy

Introduction to PEG Allergy

The American Academy of Allergy, Asthma, and Immunology recommends suspecting PEG allergy in patients with repeated anaphylactic reactions to ≥2 structurally different medications that share PEG as an excipient, and management requires strict avoidance of all products containing PEG and its derivatives, with specialized skin tests to confirm diagnosis only in centers specialized in drug allergy 1, 2, 3

PEG allergy should be considered in the following specific clinical situations: repeated anaphylactic reactions to ≥2 medications or products that share PEG as a common excipient, reactions to high-risk medications such as injectable corticosteroids, hormones, or PEG-based laxatives 1, 2, 3

The diagnostic approach for PEG allergy includes skin tests, such as prick test (SPT) and intradermal test (IDT), with PEG3350, and metilprednisolona acetato, as well as oral provocation tests to determine tolerance to excipients in low concentrations 1, 2, 3, 4

The management of PEG allergy involves strict avoidance of products containing PEG, including laxatives, injectable corticosteroids, and hormones, and consideration of alternative therapeutic options, such as magnesium oxide or lactulosa for laxatives, and metilprednisolona succinato sódico for corticosteroids 1, 2, 3, 5

Patients with PEG allergy may tolerate oral formulations with low concentrations of PEG, but may still have anaphylactic reactions to other medications containing PEG, and should be considered for COVID-19 vaccination with mRNA vaccines that incorporate PEG, but with caution and prior skin testing for PEG and polisorbate 1, 6
The American Academy of Allergy, Asthma, and Immunology recommends documenting PEG allergy clearly in the medical record with all its synonyms, and educating patients on all synonyms of PEG to avoid products that contain it 1