Use of antihistamines for COVID-19 vaccine recipients with risk of anaphylaxis

Allergic reactions to COVID-19 vaccine ranging from mild to severe have been reported in patients with a history of anaphylaxis. Currently, no guidelines are available regarding prevention of allergic reactions in patients with high-risk of anaphylaxis who plan on receiving the SARS-CoV-2 vaccine. In this case-series study, two patients with a history of anaphylaxis had taken antihistaminic drugs prior to their BNT162b2 vaccinations and experienced no major allergic reactions afterwards. The use of antihistamines prior to COVID-19 vaccination may have affected the outcome of the two subjects with history of anaphylaxis history. However, further studies are needed to evaluate efficacy, generalizability and safety of the approach presented in this case-series.