What are the vaccine’s side effects?

The most common side effects of these vaccines are the symptoms you feel when your immune system is working really hard. They are not unexpected – your body is building up a defense against the virus and some people feel that response more than others. A bit of a sore arm just like after any shot is to be expected, and some people report feeling tired, having some joint or muscle aches, and maybe even a fever. These typically go away within a few days and for those vaccines that require a second dose, the symptoms may be a little stronger after that second round.

Just like with all medications, there is always a risk of allergic reaction. That risk is highest in people who have a history of allergic reactions – so it’s very important to talk to your provider about all allergies that you have and also to stay around for the observation period after you receive the vaccine just in case. Serious allergic reactions are very rare, and they usually happen in the first half an hour or so after the vaccine, but all vaccination sites are required to be equipped to handle an allergic reaction if it occurs.