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Most people don’t have any serious side effects from vaccines. The most common side effects—like soreness where the shot was given—are usually mild and go away quickly on their own.
What are common side effects of vaccines?
The most common side effects after vaccination are mild. They include:
Pain, swelling, or redness where the shot was given
Mild fever
Chills
Feeling tired
Headache
Muscle and joint aches
Fainting can also happen after any medical procedure, including vaccinations.
Serious side effects from vaccines are extremely rare. For example, if 1 million doses of a vaccine are given, 1 to 2 people may have a severe allergic reaction.
Signs of a severe allergic reaction can include:
Difficulty breathing
Swelling of your face and throat
A fast heartbeat
A bad rash all over your body
Dizziness and weakness
If you experience a severe allergic reaction, call 9-1-1, or go to the nearest hospital. Call your vaccination provider or your healthcare provider if you have any side effects that bother you or do not go away. Please report any potential side effects experienced from vaccination to the Vaccine Adverse Event Reporting System, a program co-managed by the U.S. Centers for Disease Control and Prevention and the Food and Drug Administration to ensure that all recommended vaccines remain safe.
In the very rare event that a vaccine causes a serious problem, the National Vaccine Injury Compensation Program (VICP) may offer financial help to individuals who file a petition. Learn more about VICP. The Countermeasure Injury Compensation Program (CICP) may help pay for the costs of medical care and other expenses for people seriously injured from a COVID-19 vaccine. Learn more about the CICP.
In the very rare event that a vaccine causes a serious problem, the National Vaccine Injury Compensation Program (VICP) may offer financial help to individuals who file a petition. Learn more about VICP.
Do childhood vaccines cause autism?
No. Vaccines do not cause autism. Many studies have looked for a link between vaccines and autism, and the research clearly shows that vaccines don’t cause autism. Learn more about these studies and autism.
Getting immunized is easy. Vaccines and preventive antibodies are available at the doctor’s office or pharmacies — and are usually covered by insurance.
Content created by Office of Infectious Disease and HIV/AIDS Policy (OIDP) Content last reviewed
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