Here's What You Need to Know About COVID Vaccine Side Effects If You Have Cosmetic Fillers

Shortly before the new year, the Food and Drug Administration reported a new and somewhat unexpected COVID-19 vaccine side effect: facial swelling.

Two people — a 46-year-old and a 51-year-old — who'd received the Moderna COVID-19 vaccine during clinical trials experienced "temporally associated" (meaning on the side of the face) swelling within two days of receiving their second dose of the shot, according to the report. The suspected cause of the swelling? Cosmetic filler. "Both subjects had prior dermal filler," the FDA stated in the report. The agency didn't share any more information, and a publicist for Moderna did not return Shape's request for comment before publication.

If you have cosmetic fillers or have been considering them, you probably have some questions about what to expect if and when you get a COVID-19 vaccine — whether from Moderna, Pfizer, or any other companies that could soon receive emergency use authorization from the FDA. Here's what you need to know.

First, how common is this side effect from the vaccine?

Not very. Facial swelling isn't included in the list of common side effects of the COVID-19 vaccine from the Centers for Disease Control and Prevention. And the FDA has documented just two reports of this side effect out of more than 30,000 people who participated in the Moderna clinical trials (so far, the side effect hasn't been reported with Pfizer's vaccine or any other company's COVID-19 vaccines).

That said, STAT, a medical news site that live-blogged the FDA's presentation of this data in December, reported a third person in the Moderna trial who said they developed lip angioedema (swelling) roughly two days after vaccination (it's unclear whether this was after the person's first or second dose). "This person had received prior dermal filler injections in the lip," Rachel Zhang, M.D., an FDA medical officer, said during the presentation, according to STAT. Dr. Zhang didn't specify when this person had gotten their filler procedure. (

While the FDA didn't say how many people in the Moderna trial had cosmetic fillers, nearly 3 million people in the U.S. get fillers every year, according to the American Society of Plastic Surgeons — so, it's a pretty common procedure. But with only three incidences of facial swelling in a trial that involved more than 30,000 people, that means there's an approximate 1 in 10,000 chance of developing facial swelling after getting the COVID-19 vaccine. In other words: It's unlikely.

Why might someone with fillers have swelling after getting the COVID-19 vaccine?

The exact reason is unclear at this point, but the swelling is "likely some cross-reactive substance between the vaccine and the ingredients in the filler," says infectious disease expert Amesh A. Adalja, M.D., senior scholar at the Johns Hopkins Center for Health Security.

The Moderna vaccine's ingredients include mRNA (a molecule that essentially teaches your body to create its own version of the COVID-19 virus's spike protein as a way to prepare your body to protect itself from the virus), several different types of lipids (fats that help carry the mRNA to the right cells), tromethamine and tromethamine hydrochloride (alkalizers that are commonly used in vaccines to help match the pH level of the vaccine to that of our bodies), acetic acid (a natural acid normally found in vinegar that also helps maintain the vaccine's pH stability), sodium acetate (a form of salt that acts as another pH stabilizer for the vaccine and is also commonly used in IV fluid), and sucrose (aka sugar — yet another common stabilizer ingredient for vaccines in general).

While one of the vaccine's lipids, polyethylene glycol, has been linked to allergic reactions in the past, Dr. Adalja says it's difficult to know whether this ingredient — or any other, for that matter — is specifically involved in swelling in people with fillers.

The FDA's report didn't detail exactly what type of cosmetic fillers these patients had received. The American Academy of Dermatology states that the most common filler ingredients, in general, include fat that's taken from your own body, hyaluronic acid (a sugar found naturally in the body that gives skin dewiness, bounce, and radiance), calcium hydroxylapatite (basically an injectable form of calcium that helps stimulate the skin's collagen production), poly-L-lactic acid (an acid that also boosts collagen formation), and polymethylmethacrylate (another collagen booster). Each of these fillers can come with its own unique side effects and cross-reactions. But since the FDA didn't specify what type (or types) of fillers these people had, "it's unclear what the cross-reactivity may be," says Dr. Adalja. "There are a lot more questions that need to be answered." (

Interestingly, the person who had reportedly experienced lip swelling after their Moderna COVID-19 vaccination said they "had a similar reaction after a previous influenza vaccine," Dr. Zhang said during the FDA's presentation of Moderna's vaccine data, according to STAT.

One possible explanation for this side effect — whether from Moderna's COVID-19 vaccine, a flu shot, or any other vaccine — is that "the intended activation of the immune system by the vaccine could also be triggering inflammation at other sites in the body," says Jason Rizzo, M.D., Ph.D., director of Mohs Surgery at Western New York Dermatology. "Since dermal filler is essentially a foreign substance to the body, it makes sense that these areas would become more prone to inflammation and swelling in this type of scenario," he explains. (FYI: Dermal filler isn't the same as Botox.)

What to Do If You've Had Fillers and Plan to Get a COVID-19 Vaccine

More data is being collected on the side effects of COVID-19 vaccines as a whole, but it's important to pay attention to what's been reported so far — even side effects that have only been seen in very small numbers. With that in mind, Dr. Adalja says it's a good idea to talk to your primary care physician if you've had fillers and are planning to get vaccinated against COVID-19.

If you get the go-ahead, just make sure you hang out in your medical care provider's office for about 15 to 30 minutes after you've been vaccinated. (Your provider should follow CDC guidelines and recommend this anyway, but it never hurts to repeat it.) "If you do get swelling, it can be treated with steroids or antihistamines, or some combination of them," says Dr. Adalja. If you happen to develop facial swelling (or any other unexpected side effect, for that matter) after you've been vaccinated and leave the vaccination site, Dr. Adalja suggests calling your doctor ASAP to figure out the right treatment.

And, if you notice facial swelling (or any other concerning side effects) after the first dose of your COVID-19 vaccine, be sure to talk to your doctor about whether or not it's a good idea to get the second dose, says Rajeev Fernando, M.D., an infectious disease specialist working in COVID-19 field hospitals across the country. Also, if you're concerned about what might have caused the swelling, Dr. Fernando suggests talking to an allergist, who may be able to run some tests to see what could be behind the side effect.

Dr. Adalja stresses that this news shouldn't keep you from getting vaccinated, even if you have or are considering getting fillers in the near future. But, he says, "you might want to be a little more mindful of the symptoms you experience after receiving the vaccine, if any, and keep an eye on the areas where you had filler."

Overall, though, Dr. Adalja says that the "risk-benefit ratio favors getting the vaccine."

"We can treat swelling," he says, but we can't always successfully treat COVID-19.

The information in this story is accurate as of press time. As updates about coronavirus COVID-19 continue to evolve, it's possible that some information and recommendations in this story have changed since initial publication. We encourage you to check in regularly with resources such as the CDC, the WHO, and your local public health department for the most up-to-date data and recommendations.