Most patients with allergic reactions to first COVID-19 vaccine receive second dose safely
Click Here to Manage Email Alerts
Although the CDC lists a severe or immediate allergic reaction to the first dose of an mRNA COVID-19 vaccine as a contraindication for the second dose, a study found most individuals with a dose one reaction received dose two safely.
However, the results, published in The Journal of Allergy and Clinical Immunology: In Practice, also showed a limited role for excipient skin testing among patients with a reaction to the first dose.
The Pfizer-BioNTech and Moderna mRNA COVID-19 vaccines include polyethylene glycol 2000 (PEG-2000), which has been examined as a possible cause of allergic reactions, though supportive evidence has been limited, Anna R. Wolfson, MD, an instructor at Harvard Medical School and an allergist and immunologist at Massachusetts General Hospital, and colleagues wrote. Meanwhile, the Janssen adenovirus vector vaccine includes polysorbate 80.
The researchers aimed to discover if there is a relationship between allergies to these excipients and allergic reactions to the vaccines. They also evaluated the outcomes associated with excipient skin testing following allergic reactions to the first dose of the vaccine.
Out of 38,933 Moderna doses and 25,906 Pfizer-BioNTech doses administered between Jan. 6 and March 3, 2021 at Mass General Brigham (MGB), the analysis included 80 patients (89% women; 78% white, mean age, 40.9 years ± 13.6 years) who had an allergic reaction to the first dose. Researchers assessed these patients using a risk stratification algorithm, which uses a clinical history with excipient skin testing to evaluate higher risk individuals.
Of those patients who had an allergic reaction, 65 experienced symptoms within 30 minutes of vaccination, 11 had symptoms within 24 hours of receiving the first dose and four developed symptoms 24 hours or more later.
The immediate reactions involved 51 patients (78%) who experienced cutaneous symptoms, 14 patients (22%) who had lower respiratory symptoms, 10 patients (15%) with cardiovascular symptoms and 21 patients (32%) whose subjective symptoms included lightheadedness and tingling.
The researchers categorized 21 of these reactions (32%) as grade 0, 33 reactions (51%) as grade 1 and 11 reactions (17%) as grade 2. None of these patients experienced long-term sequalae after their reactions.
The most common delayed symptoms were cutaneous (n = 14; 93%), with one patient treated in the ED.
The researchers used MiraLAX (Bayer Healthcare-Schering-Plough), a laxative that includes PEG-3350, to conduct PEG skin testing. They also used Refresh Tears (Allergan) to conduct polysorbate 80 testing. Overall, 12 patients had positive skin tests to polysorbate 80, and five had positive skin tests to PEG.
Providers advised patients who had negative skin testing to get their second dose of the COVID-19 vaccine. When 70 of these patients (88%) received the second dose, 52 patients (74%) had no reaction, and 10 patients (14%) experienced a mild reaction managed with antihistamines. Two patients required epinephrine.
The results of the skin testing did not impact the tolerance of the second dose among patients who had immediate or delayed reactions, the researchers wrote. Also, three patients who had positive PEG-3350 testing tolerated the second dose. Refresh Tears, however, caused nonspecific irritation.
The researchers concluded that excipient skin testing may be of little use in assessing reactions to the first dose of the vaccine and suggested that more data about the value of skin prick testing for PEG in evaluating patients with mRNA COVID-19 vaccine anaphylaxis is necessary. Further, they recommended that Refresh Tears not be used in skin testing.
The study’s population was a referred population consisting of MGB patients evaluated by a specialist and that most of its subjects were white females, the researchers wrote, limiting its generalizability.
The study’s data also are subject to information bias, the researchers wrote, because they could not say why some patients did not receive their second dose even when allergists advised that it was safe. Symptoms were self-reported as well.