Speak to your GP or practice nurse if:
- you're worried about you or your child having a vaccine
- you're not sure if you or your child can have a vaccine
You could also ask a health visitor any questions you have about vaccines.
What's in a vaccine?
Most people are not concerned about vaccine ingredients and know that they are safe.
The main ingredient of any vaccine is a small amount of bacteria, virus or toxin that's been weakened or destroyed in a laboratory first.
This means there's no risk of healthy people catching a disease from a vaccine. It's also why you might see vaccines being called "live" or "killed" vaccines.
Other vaccine ingredients
Vaccines sometimes contain other ingredients that make the vaccine safe and more effective.
There is no evidence that any of these ingredients cause harm when used in such small amounts.
A full list of any vaccine's ingredients is available on the electronic medicines compendium (emc) website.
Read more about specific vaccine ingredients on the Oxford University Vaccine Knowledge Project website.