Healthcare professionals have given more than 553 million COVID-19 vaccine doses as of February 2022, according to the Centers for Disease Control and Prevention (CDC). These vaccines can help prevent hospitalizations, serious illness, or death as a result of COVID-19.

Researchers carefully track the side effects of the COVID-19 vaccine. Side effect considerations were an important part of clinical trials before the Food and Drug Administration (FDA) approved the vaccines and will remain in consideration as more people get the vaccine.

Here’s what you should know about COVID-19 vaccine side effects.

As with all vaccines, side effects may occur after getting the COVID-19 vaccine. These include:

  • chills
  • fatigue
  • fever
  • headache
  • muscle pain
  • nausea
  • pain at the injection site
  • redness at the injection site
  • swelling at the injection site

According to the CDC, some people experience more side effects after getting a second dose, but this isn’t always the case. Generally, you can expect vaccine side effects to be mild to moderate.

What are the chances of getting serious side effects from the COVID-19 vaccine?

Serious COVID-19 vaccine side effects are very rare. However, if a person were to experience serious side effects, they are most likely to occur in the first 6 weeks after vaccination.

According to the CDC, researchers have identified four adverse event types that have occurred. These include:

  • Anaphylaxis. Anaphylaxis is a severe and potentially life threatening allergic reaction that can cause breathing problems, hives, and low blood pressure. Less than 0.3 percent of people receiving a COVID-19 vaccine for the first time experienced this side effect.
  • Guillain-Barré syndrome (GBS). GBS is a rare side effect that can cause the immune system to attack healthy nerve cells. Symptoms include muscle weakness and sometimes paralysis.
  • Myocarditis and pericarditis. Myocarditis is a rare COVID-19 vaccine side effect. It occurs when the heart muscle becomes inflamed. Pericarditis is when the tissue surrounding the heart swells and becomes inflamed. According to 2021 research, doctors most often associate these side effects with mRNA vaccines, such as Moderna and Pfizer-BioNTech.
  • Thrombosis with thrombocytopenia syndrome (TTS). TTS is a rare side effect that can cause blood clots or increased blood clotting, which can potentially be life threatening. Doctors associate this side effect most commonly with Johnson & Johnson’s Janssen COVID-19 vaccine.

As of May 5, 2022, the FDA changed the Emergency Use Authorization (EUA) granted to the Johnson & Johnson vaccine, limiting authorization. This decision follows an analysis of the safety concerns regarding thrombosis with thrombocytopenia syndrome (TTS). Authorization of the Johnson & Johnson vaccine is now limited to people ages 18 years and older who can’t receive other approved COVID-19 vaccines or who would choose not to get vaccinated otherwise. Individuals who cannot receive other COVID-19 vaccines includes those for whom it is not clinically appropriate or who don’t have access to the Moderna or Pfizer vaccine.

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Federal agencies continue to track and investigate both mild and severe side effects of COVID-19 vaccines.

COVID-19 vaccines are now FDA approved for those ages 5 and up. Here are some of the side effects reported by age.


FDA approval of the COVID-19 vaccine for children ages 5 to 11 happened in October 2021. Because of this, there’s less data on vaccine side effects in children. However, clinical trials where researchers tested the vaccines in children revealed no serious side effects, according to 2021 research.

The most common side effects from the study were similar to those of adults. These included pain at the injection site, fatigue, chills, and headache. The most common symptom in children was mild to moderate fever.

Young adults

A 2021 study of vaccine side effects published in JAMA found that younger adults were more likely to have adverse side effects than older adults.

Another 2021 study found young adults and adolescent males were the most likely to experience myocarditis as a vaccine side effect. The study found that 79 percent of reported myocarditis events were in men.

Older adults

Older adults are less likely to have vaccine side effects than younger adults, according to the earlier study by JAMA.

The FDA has approved three COVID-19 vaccine brands in the United States: Pfizer-BioNTech, Moderna, and J&J vaccines.

U.S. adults have received more than 284 million doses of the Pfizer vaccine, making it the most common COVID-19 vaccine, while just more than 17 million J&J doses have been given.

There’s still a lot of research to be done comparing the effects of each vaccine. The 2021 JAMA study of nearly 20,000 people who received a COVID-19 vaccine found adverse side effects were more commonly reported in mRNA vaccines like Moderna and Pfizer than in the non-mRNA vaccine (J&J).

However, the fact that far fewer people have received the non-mRNA vaccine could explain the difference in reported outcomes.

If you have a severe allergic reaction after getting a COVID-19 vaccine, the CDC recommends that you avoid getting another dose of the same vaccine type.

For example, if you have an allergic reaction to the Pfizer-BioNTech vaccine, avoid the Moderna vaccine (and vice versa) since they work in the same way.

Some people will experience mild side effects from the COVID-19 vaccine, while others may have none.

Your side effects (or lack thereof) don’t mean the vaccine will work better for you than another person. The vaccine can help protect you regardless of your body’s response.

If you experience side effects from the COVID-19 vaccine, here are some measures that may help:

  • Apply cold compresses to the injection site.
  • Drink plenty of fluids.
  • Perform light stretches to relax your arm muscles.
  • Take over-the-counter pain relievers like acetaminophen, ibuprofen, or aspirin (but only for those older than age 18).
  • Rest and give your body time to recover.

If you experience a significant side effect of the COVID-19 vaccine, report it to the Vaccine Adverse Event Reporting System. This resource can also be used to report any new side effects you haven’t heard mentioned before.

At the start of the COVID-19 pandemic, there were no readily available protections or treatments for the coronavirus. Since then, more than 900,000 people in the United States have died from the coronavirus.

The COVID-19 vaccine has helped protect people against the coronavirus. According to the CDC, people who are unvaccinated have higher diagnosis and death rates than people who are vaccinated.

People who are vaccinated, especially those ages 65 and older, can further reduce their risk by receiving a booster dose.

While creating a vaccine without side effects would be revolutionary, all vaccines have the potential for side effects. In the case of the COVID-19 vaccine, very few adverse events have been reported, and many worldwide health groups are monitoring side effects closely.

If you have questions about COVID-19 vaccine side effects, talk with a healthcare professional. They can help you evaluate the risks and benefits so you can make the most informed choice.