COVID-19 Vaccine (Pfizer)
Adverse Reactions and Events


The most common adverse reactions reported after vaccination are: 

  • Pain at the injection site 84.1%
  • Fatigue 62.9%
  • Headache 55.1%
  • Muscle pain 38.3%
  • Chills 31.9%
  • Joint pain 23.6%
  • Fever 14.2%
  • Injection site swelling 10.5%
  • Injection site redness 9.5%

Severe allergic reactions have been reported.

Adverse reactions associated with vaccination, some of which may be serious and unanticipated, were not seen in clinical trials but may become apparent with widespread use. 

adverse reactions




COMIRNATY and Pfizer-BioNTech COVID-19 Vaccine

Vaccine Adverse Event Reporting System

ACIP General Best Practice Guidelines for Immunization; Preventing and Managing Adverse Reactions

Preparing for the Potential Management of Anaphylaxis at COVID-19 Vaccination Sites



Page last reviewed: October 8, 2021