Language selection


Reported side effects following COVID-19 vaccination in Canada

We update this page every second Friday at noon Eastern Time. A detailed technical report is available.

Changes to the update schedule

Please note that due to the holidays, the May 27 report will be published on May 30, 2022.

Summary of this week's report updated May 13, 2022

Additional information

Canada’s independent drug authorization process is known around the world for its high standards and rigorous review process. Decisions are based on scientific and medical evidence. Vaccines authorized for use in Canada are safe, effective and of high quality.

The work to make sure a vaccine is safe starts before the regulatory process even begins. Exploratory, preclinical studies, and clinical trials are designed to assess the vaccine’s safety. Evidence from these activities is submitted to Health Canada for regulatory review. Health Canada’s scientific and medical reviewers then conduct a thorough and independent review of all vaccine data. Only then is a vaccine authorized for use in Canada. Learn more about how vaccines are approved in Canada.

Health Canada authorized booster doses of Pfizer-BioNTech Comirnaty on November 9, 2021 and Moderna Spikevax on November 12, 2021. Booster doses are administered into the muscle (intramuscularly) to adults at least 6 months after they complete their primary series. On November 19, 2021, the authorization of Pfizer-BioNTech Comirnaty was extended to children 5 to 11 years of age (10 mcg dose). On March 17, 2022, the authorization of the Moderna Spikevax COVID-19 vaccine was extended to children 6 to 11 years of age (50 mcg dose). Health Canada authorized the AstraZeneca Vaxzevria COVID-19 vaccine on November 19, 2021 and the Janssen COVID-19 vaccine on November 23, 2021 under the Food and Drug Regulations.

Health Canada authorized Novavax Nuvaxovid COVID-19 vaccine on February 17, 2022 and Medicago Covifenz COVID-19 vaccine on February 24, 2022. Novavax Nuvaxovid COVID-19 vaccine is for people 18 years of age and above, and Medicago Covifenz COVID-19 vaccine is for people 18 to 64 years of age. Both are administered as a 2-dose regimen, 21 days apart.

Get more information about the authorized vaccines:

After a vaccine is authorized, Health Canada, PHAC, manufacturers, and public health authorities continue to review and monitor the adverse event (side effect) data as vaccines are administered to individuals in Canada.

Drug manufacturers (or sponsors) must also monitor and act on safety issues. They develop and update detailed product monographs, which explain how to safely and effectively use a drug or vaccine. The most recent product monographs for approved COVID-19 vaccines are in the COVID-19 vaccines and treatments portal. Health Canada regularly updates a post-authorization activity table (PAAT) for each COVID-19 vaccine and treatment. The PAAT summarizes activities since authorization. This includes product monograph updates for each vaccine authorized for use in Canada:

Some people have reported adverse events (side effects) after being immunized with a COVID-19 vaccine in Canada. These adverse events aren’t necessarily related to the vaccine. For example, they may be:

If you experience an adverse event following immunization with a COVID-19 vaccine in Canada, please contact your healthcare provider. Learn more about reporting adverse events.

Did you find what you were looking for?

What was wrong?

(Don’t include any personal information. Note that you will not receive a reply.)
Maximum 300 characters

Thank you for your feedback

Date modified: