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What are the side effects from the vaccine?

Like any medicine, the COVID-19 vaccines can sometimes cause mild side effects. Serious side effects are incredibly rare

Common side effects are generally mild and might include tenderness, redness, or swelling at the injection site, headache, low fever, or you may feel unwell. These are more common after the second dose than the first. If you experience symptoms like this, they won’t last long and they are much milder than what COVID-19 can cause. 

Side effects occur because the vaccine triggers your immune system to start fighting. If they last longer than a week, or you get a high fever, contact your doctor or seek medical attention. If you do not experience any side effects, it does not mean the vaccine wasn’t effective for you.

In extremely rare cases, a serious allergic reaction known as anaphylaxis could occur. This is why you are asked to stay for about 15 minutes after your immunization, to ensure medical help is available if you have a rare reaction.

The COVID-19 vaccines are safe. Physicians are confident in the short term and long term safety of the vaccines.

If you’re concerned about side effects or allergies, talk to your doctor. You can also review the following resources:

Allergies and the COVID-19 vaccine (Q&A on this site)

Physicians confident in long-term safety of vaccines (Q&A from this site)

Health Canada: Possible side effects

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