Possible Side Effects After Getting a COVID-19 Vaccine

COVID-19 vaccination will help protect people from getting COVID-19. Adults and children may have some side effects from the vaccine, which are normal signs that their body is building protection. These side effects may affect their ability to do daily activities, but they should go away in a few days. Some people have no side effects, and allergic reactions are rare.

Serious side effects that could cause a long-term health problem are extremely unlikely following any vaccination, including COVID-19 vaccination. Vaccine monitoring has historically shown that side effects generally happen within six weeks of receiving a vaccine dose. For this reason, the U.S. Food and Drug Administration (FDA) collected data on each of the authorized COVID-19 vaccines for a minimum of two months (eight weeks) after the final dose. CDC is continuing to monitor the safety of COVID-19 vaccines even now that the vaccines are in use.

Common Side Effects

Helpful Tips to Relieve Side Effects

Talk to a doctor about taking over-the-counter medicine, such as ibuprofen, acetaminophen, aspirin (only for people age 18 or older), or antihistamines for any pain and discomfort experienced after getting vaccinated.

People can take these medications to relieve side effects after vaccination if they have no other medical reasons that prevent them from taking these medications normally. Ask your child’s healthcare provider for advice on using a non-aspirin pain reliever and other steps you can take at home to comfort your child after vaccination.

It is not recommended to take these medicines before vaccination for the purpose of trying to prevent side effects.

After a Second Shot

Side effects after the second shot may be more intense than the ones experienced after the first shot. These side effects are normal signs that the body is building protection and should go away within a few days.

If You Received a Booster Shot

So far, reactions reported after getting a booster shot were similar to those after the two-dose or single-dose primary series. Fever, headache, fatigue and pain at the injection site were the most commonly reported side effects, and overall, most side effects were mild to moderate. However, as with the two-dose or single-dose primary series, serious side effects are rare, but may occur.

When to Call the Doctor

Side effects can affect you or your child’s ability to do daily activities, but they should go away in a few days.

In most cases, discomfort from pain or fever is a normal sign that the body is building protection. Contact a doctor or healthcare provider:

• If the redness or tenderness where the shot was given gets worse after 24 hours
• If the side effects are worrying or do not seem to be going away after a few days

Remember

• The Pfizer-BioNTech COVID-19 vaccine and Moderna COVID-19 vaccine both need 2 shots to complete the primary series. Adults and children ages 5 years and older should get the second shot even if they have side effects after the first shot, unless a vaccination provider or doctor says not to get it.
  • CDC recommends that moderately to severely immunocompromised people ages 12 years and older who completed their Pfizer-BioNTech COVID-19 vaccine primary series and ages 18 years or older who completed their Moderna COVID-19 vaccine primary series should plan to get an additional primary dose followed by a booster shot. This additional primary dose is intended to improve immunocompromised people’s response to their primary vaccine series
  • COVID-19 vaccine booster shots are recommended for some people ages 18 years and older who completed their primary vaccination series with the Pfizer-BioNTech or Moderna COVID-19 vaccines at least 6 months ago.

• The J&J/Janssen COVID-19 vaccine needs a single shot to complete the primary series. Learn more about the different COVID-19 vaccines.
  • People ages 18 years and older should receive a booster shot at least 2 months after receiving their J&J/Janssen COVID-19 vaccine.
• It takes time for the body to build protection after any vaccination. People are considered fully vaccinated 2 weeks after their second dose of the Pfizer-BioNTech or Moderna COVID-19 vaccine, or two weeks after the single-dose J&J/Janssen COVID-19 vaccine. You should keep using all the tools available to protect yourself or your child until fully vaccinated.
• Millions of people have received COVID-19 vaccines, and no long-term side effects have been detected.
• There is no evidence that COVID-19 vaccines cause fertility problems.
• CDC continues to closely monitor the safety of COVID-19 vaccines. If scientists find a connection between a safety issue and a vaccine, FDA and the vaccine manufacturer will work toward an appropriate solution to address the specific safety concern (for example, a problem with a specific lot, a manufacturing issue or the vaccine itself).

If you or your child is fully vaccinated, you can participate in many of the activities that you did prior to the pandemic. Learn more about what you can do when you have been fully vaccinated.

If you would like to report an adverse event, side effect or reaction from the COVID-19 vaccine, please use the following link: https://vaers.hhs.gov/external icon