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All of the ingredients in vaccines are safe in the amounts used. You may have heard or read that some vaccine ingredients are harmful, but this is true only at much higher amounts than those present in vaccines. Any substance, even water, can be harmful at a high dose.
What's in vaccines?
The ingredients in vaccines are necessary and are safe in the amounts used.
All vaccine ingredients serve a specific purpose in either making the vaccine, or ensuring that the vaccine is safe and effective.
This section describes some vaccine ingredients people often ask about, including why they are in vaccines and their safety. Click on the vaccine ingredient to learn more.
Safety of vaccine ingredients
Vaccine ingredients have been carefully studied for a long time and are safe in the small amounts used.
The ingredients in vaccines have not been proven to cause harm (disease or illness) in the small amounts used in vaccines, with the exception of allergic reactions in people with hypersensitivity to a specific ingredient. Before administering a vaccine, your health care provider will:
- Ask you about any known allergies or previous reactions to vaccines.
- Assess whether any given vaccine is not safe for you to receive.
If you have an unexpected allergic reaction after receiving a vaccine, your health care provider will be able to recognize and treat it quickly.
Ingredients in specific vaccines
Part 1 of the Canadian Immunization Guide has a table that lists the ingredients in vaccines used in Canada.
The Government of Canada website lists the ingredients in each COVID-19 vaccine.
You can also find a list of vaccine ingredients in the vaccine's product monograph. Product monographs are available through Health Canada's Drug Product Database.