ABSTRACT
This case reports a woman in her 40s with a history of allergic reaction to shellfish and iodine who presented with tongue angioedema, difficulty breathing and chest tightness after receiving the first dose of the Pfizer-BioNTech (BNT162b2) COVID-19 vaccine. Her angioedema remained for 10 days post-exposure to the vaccine, requiring 3 days of epinephrine infusion. She was discharged with advice to avoid further mRNA vaccines. This case highlights the increasing awareness needed of polyethylene glycol (PEG) allergy and the protracted nature of her reaction. A firm conclusion cannot be reached based on a single case report. More research is needed to understand whether there is a causal relationship between the BNT162b2 vaccine and PEG allergy. Awareness regarding PEG allergy and the complexities associated with it is important and needs to be raised due to its prevalent use in diverse industries.