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Recommendations for Fully Vaccinated People
COVID-19 Homepage
Possible Side Effects After Getting a COVID-19 Vaccine
CDC is reviewing this page to align with updated guidance.
COVID-19 vaccination helps protect people from getting severely ill with COVID-19. Side effects and adverse events could follow any vaccination, including COVID-19 vaccination.
Side effects: Not everyone experiences side effects. However, some people do. Side effects are normal signs that your body is building protection. Side effects can affect your ability to do daily activities and should go away in a few days. If you would like to report a side effect, use V-safe.
Adverse events: Adverse events are rare but could cause a long-term health problem. If an adverse event occurs, it will generally happen within six weeks of receiving a vaccine dose. If you would like to report an adverse event, use Vaccine Adverse Event Reporting System (VAERS).
- During clinical trials, 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.
- Currently, CDC, FDA, and other federal agencies continue to monitor the safety of COVID-19 vaccines.
Common Side Effects
On the arm where you got the shot:

- Pain
- Redness
- Swelling
Throughout the rest of your body:

- Tiredness
- Headache
- Muscle pain
- Chills
- Fever
- Nausea
Severe allergic reactions after COVID-19 vaccination are rare. Anyone who had a severe allergic reaction after getting an mRNA COVID-19 vaccine (Pfizer-BioNTech or Moderna) should not get another dose of either of the mRNA COVID-19 vaccines. Anyone who had a severe allergic reaction after receiving Johnson & Johnson’s Janssen (J&J/Janssen) COVID-19 vaccine, should not receive another dose of that vaccine.
Learn about getting a different type of COVID-19 vaccine after an allergic reaction.
Helpful Tips to Relieve Side Effects
To reduce pain and discomfort where the shot is given

- Apply a clean, cool, wet washcloth over the area.
- Use or exercise your arm.
To reduce discomfort from fever

- Drink plenty of fluids.
- Dress lightly.
For any pain and discomfort experienced after getting vaccinated, talk to your doctor about taking over-the-counter medicine, such as ibuprofen, acetaminophen, aspirin (only for people ages 18 years or older), or antihistamines.
- It is not recommended to take these medicines before vaccination for the purpose of trying to prevent side effects.
- 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.
After a Second Shot or a Booster 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.
So far, reactions reported after getting a booster shot are similar to those after the two-dose or single-dose primary shots. Most side effects were mild to moderate.
The most commonly reported side effects were:
- Fever
- Headache
- Fatigue
- Pain at the injection site
When to Call a Doctor about a Side Effect
In most cases, discomfort from pain or fever is a normal sign that the body is building protection. Side effects can affect you or your child’s ability to do daily activities, but they should go away in a few days. 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
Adverse events after COVID-19 vaccination are rare.
If you or your child get a COVID-19 vaccine and you think you or they might be having a severe allergic reaction after leaving the vaccination site, seek immediate medical care by calling 911.
Learn about getting a different type of COVID-19 vaccine after an allergic reaction.
If You Have No Side Effects
Reactions after getting a COVID-19 vaccine can vary from person to person. Most people in clinical trials experienced only mild side effects, and some of them had no side effects at all. Those people still had a strong response to the vaccine. Vaccination protects you from severe COVID-19 infection whether or not you have side effects after vaccination.
Reporting Side Effects and Adverse Events
V-safe provides quick and confidential health check-ins via text messages and web surveys so you can quickly and easily share with CDC how you or your dependent feel after getting a COVID-19 vaccine.
If you would like to report an adverse event, side effect, or reaction from the COVID-19 vaccine, please use the Vaccine Adverse Event Reporting System (VAERS).
What to Expect after Getting a COVID-19 Vaccine
Fact sheet for healthcare workers to give after vaccination.
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