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What Are the Side Effects of the COVID-19 Vaccine in Kids? And How to Get Relief

child vaccine

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Key Takeaways

  • COVID-19 vaccines are now approved and recommended for adults and children aged 6 months and older.
  • COVID-19 vaccines side effects are generally mild to moderate in children.
  • The most common side effects are pain at the injection site, fatigue, and headaches.
  • Side effects can be effectively managed with over-the-counter medications and at-home remedies.

COVID-19 vaccines for babies and children aged 6 months and older are finally here. The Centers for Disease Control and Prevention (CDC) officially approved Pfizer’s pediatric vaccine for ages 5 to 11 on November 2, 2021.

In June 2022, Pfizer-BioNTech and Moderna vaccines for children aged 6 months on up were approved by U.S, Food and Drug Administration (FDA). These vaccines were officially recommended for children aged 6 months and older by the the CDC on June 18, 2022.

As of June 15, 2022, 10.2 million kids—and counting—have received their first dose, while 8.3 million children are fully vaccinated.

Some families are concerned about potential side effects of the vaccine. After all, many adults remember experiencing some of their own COVID-19 vaccine side effects, particularly after the second dose.

Thankfully, research shows that vaccine side effects among kids are generally mild to moderate. No severe side effects were found among the 1,517 children who received the vaccine in the Pfizer trial. Similarly, side effects have been primarily mild to moderate in babies and young children up to age 4 as well.

Verywell Family caught up with experts in the field to help parents better understand what side effects kids are likely to experience after their COVID-19 vaccine. Most importantly, we found out what parents can do to help their kids feel better.

Side Effects of Covid-19 Vaccine For Kids

Extensive research about the vaccine side effects for kids comes from the trial study data released by Pfizer. A total of 2,268 children participated in this trial, with 1,517 children receiving the vaccine, and 751 receiving a placebo. Children participating in the trial received 1/3 the dose that adults and teens have received. Your child will be receiving this smaller dose as well.

Among the children receiving the vaccine, there were no severe reactions or side effects, says José Mayorga, MD, Executive Director, UCI Health Family Health Center. There were also no severe reported allergic reactions, including no cases of anaphylaxis, he adds.

Importantly, there were no reports of myocarditis or pericarditis, a severe, but rare and manageable side effect that has been reported mainly among young men receiving mRNA vaccines like the Pfizer vaccine. It’s reassuring for most parents to hear that there were no severe side effects among trial participants.

But if there are any side effects, parents want to know all the details so they can prepare themselves and their kids. Many parents wonder if the vaccine side effects may mean missed days of school or if their kids be uncomfortable or feel sick. Let’s take a look at the possible side effects and what to know about them.

Most Common Side Effects

The trial data found that the most common side effects in kids were pain on the arm where the injection had taken place, with 71 to 74% of children experiencing this. After that, feeling tired was the next most common side effect, affecting 39% of kids.

Headache was also somewhat common, with 28% of kids experiencing one. Redness (19%) and swelling (15%) at the injection site were also relatively common.

Less Common Side Effects

The good news is that some of the more flu-like symptoms—the ones that make kids feel sick—were less common. Only 8% of kids reported having fevers after vaccination, 5% had diarrhea, and 2% experienced vomiting. 10% of kids had the chills, 12% experienced muscle pain, and 5% had joint pain.

First Shot vs. Second Shot

As was the case for adults, some kids had a tougher time with systemic side effects (fever, feeling unwell) after their second dose.

Lowell Gordon, MD, Medical Director and Pediatrician at Families Together of Orange County Community Health Center, explains that this isn’t because children are getting a different dosage for their second shot. Rather, their immune system may react differently the second time.

“More side effects may be felt after the second shot because the immune cells from the first shot are ready to respond more quickly and more aggressively the second time around,” says Dr. Gordon. But this is a good thing. “This tells us that the body is making antibodies in response as intended.”

How Long Do the Side Effects Last?

Kristina Deeter, MD, MBA, a pediatric intensivist and specialty medical officer for pediatric critical care medicine at Pediatrix Medical Group in Reno, Nevada, says that parents should expect side effects—if your child gets them—to last a few days.

That said, Dr. Deeter says that if you have any concerns about side effects affecting your child and limiting their activities, you may want to schedule their vaccine at a time when you can stay home with them should they have stronger side effects. “Try to plan the vaccination on a Friday so you can take the weekend off,” suggests Dr. Deeter.

How Do Kids’ Side Effects Compare to Adult Side Effects?

As parents consider vaccinating their children, many are remembering the side effects they experienced after getting vaccinated against COVID. Some adults experienced quite intense side effects and needed the day off from work after their shots, particularly after the second dose.

Dr. Deeter reminds parents that children aged 5 to 11 are receiving 1/3 the dosage that adults received. So far, most of the reported side effects among children have been on the milder side.

“In Pfizer’s trials in this population, there were no serious adverse effects reported, including no reports of myocarditis,” Dr. Deeter says. “I would expect that kids will experience similar mild flu-like symptoms to adults that will resolve in a couple of days.”

Dr. Mayorga notes that children have generally done quite well compared to teens and adults who received the vaccine. Published data from the CDC compares vaccine side effects among the 5 to 11-year-old cohort to that of 16-25 year-olds.

Overall, side effects were milder in the younger children. Teens and young adults experienced higher rates of fevers, fatigue, headaches, chills, and muscle pain.

Tips for Managing Side Effects

It’s not likely that your child will experience bothersome side effects, but all children are different, and some children might experience more challenging side effects than others. This may be particularly true after their second dose of vaccine.

You can rest assured, though, that there are several effective ways to soothe your child’s discomforts. Here are some doctor-approved tips.

Medications

Dr. Shanika Boyce, MD, MPH, FAAP, Pediatrician and Assistant Professor at Charles R. Drew University of Medicine and Science says that painkillers such as acetaminophen and ibuprofen can be used to relieve fever and pain. If you notice any swelling, redness, or itchiness at the vaccine injection site, you can try an antihistamine, says Dr. Boyce.

As always, make sure to contact your child's pediatrician for any dosing recommendations, and to be sure that these medications are right for your child.

Home Remedies

If your child experiences swelling, pain, or redness at the injection site, applying a cool, wet cloth can be very soothing, says Dr. Gordon. If your child develops a fever, Dr. Gordon recommends drinking plenty of fluids and dressing lightly to stay comfortable.

Dr. Deeter is a huge fan of getting some extra rest after the shot and says that chicken soup can be very helpful too (it’s not just a myth!). She recommends checking in with a pediatrician if the area where the shot was given stays red and tender for more than two days.

Addressing Parents’ Lingering Concerns

Even if you hear reassuring information about side effects, you may still have lingering fears and doubts. This is common and understandable.

Many parents are particularly concerned about long-term vaccine effects, says Dr. Deeter. Most notably, they are concerned about questions surrounding future fertility as well as genetic modifications after the vaccine, Dr. Deeter explains.

Dr. Deeter wants to reassure parents that there have been no studies showing either infertility after vaccination or evidence that the vaccine causes genetic shifts or damage.

“As pediatricians, we would absolutely never recommend a vaccine that we were concerned caused long-term side effects, especially something like infertility,” Dr. Deeter says. “There’s nothing about this vaccine that can make that modification in anyone’s body.”

In fact, many pediatricians feel so comfortable with this vaccine that they have already started eagerly giving it to their own children. Dr. Mayorga shared his own family’s story with us.

“Unfortunately, my family knows how devastating this infection can be because we have lost several loved ones to COVID-19,” Dr. Mayorga says. He decided to get his three daughters the vaccine because he was convinced it was safe and would protect his daughters against any serious effects of COVID-19.

As for his daughters’ side effects? All three of them did well; his oldest daughter had some fatigue, but she was good as new within 24 hours.

“The major 'side effect' my wife and I observed was the ice cream eating that followed,” he shares, adding, “As a doctor, but more importantly as a dad, I know getting the vaccine will help protect my daughters and they will enjoy more things without worrying about getting COVID-19.”

What This Means For You

All the doctors we spoke to agreed that COVID-19 vaccine side effects in children are generally mild and manageable. They also assured parents that any uncomfortable side effects can be effectively managed with over-the-counter medication, and at-home comforts like cold compresses, rest, and extra fluids.

If you have any questions about the vaccines or their side effects, you should contact your child’s pediatrician. They know your child and their health history and can address any continued questions or concerns you may have.

8 Sources
Verywell Family uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Centers for Disease Control and Prevention. Stay up to date with your COVID-19 vaccines.

  2. Centers for Disease Control and Prevention. COVID-19 vaccine side effects in children and teens.

  3. Centers for Disease Control and Prevention. CDC recommends pediatric COVID-19 vaccine for children 5 to 11 years.

  4. Centers for Disease Control and Prevention. CDC recommends COVID-19 vaccines for young children.

  5. American Academy of Pediatrics. Children and COVID-19 vaccination trends.

  6. Barnett E, Domachowske J, Gurtman A, et al. Evaluation of the BNT162b2 Covid-19 vaccine in children 5 to 11 years of age. New Eng J Med. 2021;386:35-46. doi:10.1056/NEJMoa2116298

  7. Centers for Disease Control and Prevention. COVID-19 vaccines for children and teens.

  8. Gurtman A. BNT162b2 (COVID-19 vaccine, mRNA) vaccine in individuals 5 to <12 years of age.

By Wendy Wisner
Wendy Wisner is a lactation consultant and writer covering maternal/child health, parenting, general health and wellness, and mental health. She has worked with breastfeeding parents for over a decade, and is a mom to two boys.