Allergic Reactions After the Administration of COVID-19 Vaccines.

Background: Data on allergic reactions after the administration of coronavirus disease (COVID-19) vaccines are limited. Our aim is to analyze reports of allergic reactions after COVID-19 vaccine administration. Methods: The Vaccine Adverse Event Reporting System database was searched for reported allergic reactions after the administration of any of the COVID-19 vaccines from December 2020 to June 2021. After data mapping, the demographic and clinical characteristics of the reported cases were analyzed. Potential factors associated with anaphylaxis were evaluated using multivariable logistic regression models. Results: In total, 14,611 cases were reported. Most cases of allergic reactions comprised women (84.6%) and occurred after the first dose of the vaccine (63.6%). Patients who experienced anaphylaxis were younger (mean age 45.11 ± 5.6 vs. 47.01 ± 6.3 years, P < 0.001) and had a higher prevalence of a history of allergies, allergic rhinitis, asthma, and anaphylaxis than those who did not (P < 0.05). A history of allergies (odds ratio (OR) 1.632, 95% confidence interval (CI) 1.467-1.816, P < 0.001), asthma (OR 1.908, 95%CI 1.677-2.172, P < 0.001), and anaphylaxis (OR 7.164, 95%CI 3.504-14.646, P < 0.001) were potential risk factors for anaphylaxis. Among the 8,232 patients with reported outcomes, 16 died. Conclusions: Female predominance in allergic reaction cases after the receipt of COVID-19 vaccines was observed. Previous histories of allergies, asthma, or anaphylaxis were risk factors for anaphylaxis post-vaccination. People with these risk factors should be monitored more strictly after COVID-19 vaccination.