FDA Says 5 People in US Had Allergic Reactions after Pfizer Shot

Around five recipients of Pfizer Inc and BioNTech SE's COVID-19 vaccine in the United States have had allergic reactions this week, a top U.S. Food and Drug Administration official said on Friday during a press conference.

Dr. Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, said that a chemical called polyetheylene glycol that is an ingredient in both the Pfizer vaccine and the Moderna Inc vaccine authorized on Friday "could be the culprit" causing the reactions.