(This article was updated on 5/23/2022 to address second booster doses for certain teens.)

Sleepovers, summer camps, birthday parties, weekend hangouts — staples of a normal teenage life that have looked anything but normal since the pandemic began.

Some good news arrived for you and your teen late last spring, though, after the FDA extended the emergency use authorization of the Pfizer COVID-19 vaccine to adolescents between the ages of 12 and 15 in May 2021.

Now, teens 12-15 years of age who were vaccinated at least five months ago are also eligible for a booster dose of Pfizer. And those who are moderately or severely immunocompromised may also be eligible for a second booster dose.

But, as with anything related to your kid's health, you're likely cautious — very cautious, in fact.

Dr. Wesley Long, director of diagnostic microbiology at Houston Methodist, is here to help as you do your due diligence about getting your teen vaccinated or boosted.

The safety of vaccinating teens was examined via clinical trial and reviewed by scientific panels

Just as the initial authorization for the Pfizer vaccine in individuals 16+ was based on clinical trial data, so, too, was the decision to expand its use to teens between the ages of 12 and 15.

"After careful review of the trial data, the FDA found that the benefits of Pfizer's COVID-19 vaccine far outweigh any of its potential risks in teens within this age group," says Dr. Long.

Pfizer's trial included 2,260 teens between the ages of 12 and 15. Not only was the vaccine shown to be safe and well-tolerated in the participants who received it, the data indicates that it's as effective in teens as it is in young adults, adults and the elderly — maybe even more so.

"There were no cases of COVID-19 reported in the teens vaccinated against COVID-19 in this trial, suggesting that the Pfizer vaccine is incredibly effective at preventing symptomatic COVID-19 in teens between the ages of 12 and 15," explains Dr. Long.

The safety of a booster dose for teens was also reviewed by scientific panels

Boosters are being recommended because data is showing that protection against mild and moderate COVID-19 via the initial vaccine series declines over time — particularly for those who were vaccinated some time ago.

Added to that is the concern about the new COVID-19 variant, omicron — which is causing a sharp increase in cases.

As a result, the FDA and CDC are now recommending that teens receive a Pfizer booster shot five months after their primary vaccine series.

Both agencies diligently reviewed the data regarding the safety and effectiveness of using a single booster dose of Pfizer in individuals 12 through 15 years of age, which included real-world data from Israel and safety data from more than 6,300 individuals. It was determined that a booster dose provides continued protection against COVID-19, including the omicron variant, reducing the risk of getting seriously ill. This benefit far outweighs any potential risks in teens within this age group.

Note: A booster shot is different from a "third shot" for teens who are moderately or seriously immunocompromised and may have not responded fully to the vaccine after the first doses. If your teen is immunocompromised, he or she is eligible for an additional dose of Pfizer after 28 days have passed since his or her second shot.

Teens experience similar side effects as young adults

Whether it's your teen's first, second or booster shot, the side effects of vaccination are similar to that of young adults.

"The side effects reported by younger teens were consistent with those seen in 16+ teens and adults — with pain at the injection site being the most prominent side effect," says Dr. Long.

The most common side effects of Pfizer's COVID-19 vaccine are:

• Pain, redness or swelling at the injection site
• Fatigue
• Headache
• Chills
• Fever
• Muscle and joint pain
  
  

"If experienced, these side effects typically only last a day or so," adds Dr. Long. "In addition, side effects seem to be more common after a teen's second dose of the vaccine, which is similar to what's been seen in adults."

Of note, Pfizer's COVID-19 vaccine should not be given to teens who have a history of a severe allergic reaction to any component found within the vaccine.

Here's how the Pfizer vaccine works and is administered

If you received Moderna or Johnson & Johnson — or Pfizer, but just can't quite remember the details — here's everything you need to know about the Pfizer COVID-19 vaccine your teen will receive:

The Pfizer COVID-19 vaccine is an mRNA vaccine. By delivering a piece of harmless genetic material called mRNA, this vaccine teaches your teen's immune system how to recognize and respond to the virus that causes COVID-19. (Related: How mRNA COVID-19 Vaccines Work)

The initial vaccine series is administered in two doses, three weeks apart. When scheduling your teen's first vaccine appointment, be sure that he or she is free to get the second dose about 21 days later.

Gaining the full protection of this vaccine takes five weeks total. After receiving the second dose of the Pfizer vaccine, it will take another two weeks for your teen's immune system to complete its work of building immunity.

It's safe to get the COVID-19 vaccine or booster at the same time as the flu shot. If your teen hasn't yet received his or her flu shot, it's safe to get it at the same time as one of his or her primary doses or booster (Related: Can You Get Your Flu Shot & COVID-19 Vaccine at the Same Time?). Check with your child's doctor before getting other immunizations, though, as some may need to given several weeks after the COVID-19 vaccine. 

Your teen is eligible for a booster dose 5 months after his or her primary series. A booster shot helps prolong protective immunity against COVID-19 (Related: How Do I Know If I Need a COVID-19 Booster Shot?). If your teen is moderately or severely immunocompromised, he or she is eligible for a third dose after 28 days have passed since his or her second shot.

Here's why it's important to vaccinate your teen

Still wondering why you should vaccinate or boost your teen?

It's true that kids generally experience only a mild case of COVID-19. But Dr. Long explains why you should still vaccinate your teenager.

"First, it's possible for a teenager to develop a more severe case of COVID-19. It's less common than severe cases seen in adults, but it is possible," warns Dr. Long. "We now know that Pfizer's COVID-19 vaccine is incredibly effective and safe in this age group. Getting sick with COVID-19 is associated with much worse outcomes than the known and potential risks of receiving Pfizer's vaccine."

And when it comes to whether or not your teen really needs a COVID booster, know that, while your child could still catch COVID-19 and experience a breakthrough infection, the data show that people who have received a booster are highly protected from getting seriously sick.

"Expanding the age range for the Pfizer vaccine is a huge step toward limiting the spread of COVID-19 and keeping our families and community healthy," says Dr. Long. "The more we allow this virus to spread, the likelier it is for more COVID-19 variants to arise — including variants that are more infectious or dangerous, as well as ones that make our current vaccines less effective. Kids make up a large percentage of the population. To get a hold of this virus, we need the vast majority of the population, including teens, to get vaccinated. Fortunately, now we have a vaccine shown to be safe and effective in teens that's going to help achieve that."

Next Steps:

• If your teen needs a COVID-19 vaccine or booster, you can schedule an appointment with a primary care doctor near you or get vaccinated at a local pharmacy.