Positive skin test to pegylated drug in a patient with anaphylaxis to polyethylene glycol

Abstract We report a case of a woman who presented anaphylaxis to polyethylene glycol (PEG) associated with positive skin tests to a pegylated drug. To the best of our knowledge, this is the first case, which suggests a potential allergy to pegylated drugs in patients with anaphylaxis to PEG. With the increasing use of pegylated drugs, physicians and patients should be informed of this potential allergy because drug databases do not always clearly indicate that pegylated drugs contain PEG.