There have been many news stories about swelling in patients that have had facial fillers and the COVID vaccine, specifically the one released by Moderna.  These reports are rare (just reported in a couple of patients total), and the brands of the fillers are unknown, making it difficult to interpret these data, and also see how it impacts an individual’s risk and recommendations related to this vaccine.

Background

Vaccines are routinely administered for the prevention of many diseases caused by bacteria and viruses, and often rely on injecting a substance that is foreign, and also a bunch of other “pixie dust” (adjuvant) ingredients to get your body mad.  Why?  Because we want the body to identify the foreign substance as something that is attacking your body so that it builds an immune response to it.
The Moderna COVID-19 vaccine is different because it is based on mRNA, which makes your body’s own cells express the spike protein of the virus on its own cells, and induces your own body to attack it (by also injecting the “pixie dust” ingredients to ramp up your immune response).
Either way, most vaccines rely on substances (“pixie dust”) that make the body “angry” so that it mounts an immune response.  We, as patients getting injected, feel these as local swelling, heat, and maybe even fevers and “mild illness” type of symptoms.  Many people confuse this reaction as getting a milder form of the disease, but that is not the case, as a component of a virus is not enough to make a replicating virus in your body.  Some forms of vaccines use a live, but attenuated, form of a virus to infect you so that you build an immune response to a different virus.  This is not the case with mRNA vaccines.

Facial Filler History

Historically, fillers were made out of collagen, usually derived from a cow.  These collagen fillers gave rise to strong rejection reactions by some people, as your body is pre-programmed to attack foreign substances, and a cow-based collagen is absolutely a foreign substance.  Given the ability to cause these reactions, a “patch test” injection was given in the arm of the patient prior to injecting the face so that the patient can be monitored for a reaction prior to a more extensive treatment.
There are still cow collagen-based injectables on the market today.  If anyone is interested in getting cow collagen mixed with microarticles of PMMA (polymethyl methacrylate, a plastic used to make many industrial appliances), then there is still a product on the market today, Bellafill.  I personally wouldn’t touch the stuff (with a 10 foot pole), as injecting plastic mixed with cow collagen is not something I would recommend to a family member when much better products are available today.

Facial Fillers Today

Facial fillers are among the most common cosmetic procedures done worldwide, and most often are based on hyaluronic acid, which is a naturally occurring substance that is present between your own skin cells, much like collagen.  Whereas collagen is a protein, a polymer-based on amino acids, hyaluronic acid is a polymer based on sugar molecules.  They are made and metabolized differently by the body but occupy the space between skin cells.
Nowadays, most fillers are based on hyaluronic acid, which largely avoids the foreign body reaction that is possible with collagen injections.  They are synthesized chemically, so there are minimal issues with inducing a reaction from the body.  In fact, an ideal property of modern fillers is that they are ignored by the body.
Most fillers are packaged with lidocaine to numb the area injected while the treatment carries on, which lasts for an hour or two after treatment.  Fillers also contain buffers to match the body’s pH to make injections more comfortable.  Upon injection, the fillers may cause some local swelling of the tissues in the area of the injection, but very rarely give rise to an immune response from a patient.
The fillers dissolve gradually after injected and are broken down by the body in the same way that the body breaks down its own hyaluronic acid.  There are enzymes to make hyaluronic acid and other enzymes that break it down into smaller parts.  Fillers can last from 6-24 months depending on which filler formulation is used, and which area it is injected into.  For example, in the lips, a given filler can last 6 months, but if the same filler is used in the tear troughs, it can last over a year.
After getting reabsorbed, the patient’s tissues return to how they were prior to injection with minimal changes.

How a Vaccine May Make Fillers Swell

It is difficult to explain how a person would get swelling locally in an area treated with fillers after getting a vaccine, as they are chemically unrelated, and there is generally no response from the immune system when injecting dermal fillers.  These ideas are all speculation based on knowing how vaccines work and knowing how fillers work.
One possibility is that there was a mild reaction during filler injection that was sub-clinical, and that the vaccine “pixie dust”, when ramping up the immune system, gave this simmering reaction some more fuel.  This is possible, though one of the patients that reportedly had this reaction had the fillers injected 6 months prior.  That is a long time to have an immunological reaction “simmer”.  The lidocaine and buffers would be long gone, leaving only the filler product, the hyaluronic acid polymers, left to react.
Another possibility is that the “pixie dust” made the body recognize the hyaluronic acid filler as “foreign”, using the same reaction we do when we inject portions of a cell or virus to make the immune system recognize it.  This would lead to the filler being immediately dissolved, as one would expect the body’s reaction to being swift in the location that the filler is.  By attracting the body’s defense and inflammatory reaction, the absorption of the hyaluronic acid would be expected to be quick.  Would the body then begin seeing the body’s native hyaluronic acid as “foreign”?  We don’t know, and we don’t have information about this.

Allergic Reactions

Yet another possibility is the nature of allergic reactions.  Allergic reactions, which have been associated with all COVID vaccines (as well as bee stings, many medications, and nuts), are thankfully rare.  What are the symptoms of allergic reactions?  Shortness of breath, rashes, and swelling.  Where is the swelling most common?  The lips and face are among the first affected in allergic reactions, even when the allergic reaction is from an injection and not something orally ingested.
Could it be possible that the swelling of the lips (which at least one patient that had lip fillers had after the vaccine) is unrelated to the fillers that were injected there?  Absolutely.  We don’t have enough information to know the answer to this.  The only thing that could tell us is more information, and comparing the statistics of lip swelling in patients that have had lip fillers against people that have not had lip fillers would be a start.  The problem is that I don’t think that “Have you had cosmetic filler injections?” is in the list of questions one gets prior to having a COVID vaccine.  I know this wasn’t on the list of questions I had to answer prior to getting my first dose of the Moderna COVID vaccine.

What to do About Facial Fillers and the COVID Vaccine

The two reported cases of potential facial swelling related to dermal fillers were both treated with oral steroids (like prednisone) and antihistamines (like Benadryl), and they responded well to this.  What is the treatment for lip and facial swelling due to an allergic reaction (not related to filler)?  Steroids and antihistamines.  If they are more severe, then epinephrine (usually in the form of an Epi-pen) is administered.
I personally would not change my recommendation, which is to get the vaccine, based on these cases.  It is not clear to me that the swelling was a direct result of the previous fillers and not just an allergic reaction to the vaccine in a patient that happened to have fillers in the past.  The patients so far have done well with standard oral treatments for allergic reactions, which is reassuring.
The COVID vaccines are our only way to gain immunity to this strain of coronavirus without catching the virus.  They are our only way to protect the most sensitive in our communities, and to shorter the pandemic season, which has already taken huge tolls on some of our most vulnerable, as well as health care providers, front line workers, and the general public.  People say that they are unsure about the safety of this vaccine based on their limited information they have read or heard.  I agree there may be some truth to this, because vaccines usually take years to develop, and years to test.  However, we know that COVID can have lethal consequences in otherwise healthy people, and it also has lung disease among other chronic illness associated with it, so you have to weigh the risks of the vaccine against the long term risks of getting the illness if you want to be fair.  Based on the information available, as well as the trajectory of this illness, getting the vaccine once it is offered to you is the best advice I can give.

About this Post

The views in this post are based solely on public information and reports in the news media, as there are no reports in available medical literature with more details about the patients, reactions, and treatments received (as of the time of writing this post).  They represent my personal beliefs about the virus, fillers, and the vaccine based on my experience.  I will try to update this blog post with new information as it becomes available.

Update 1/7/2021

The CDC has acknowledged some of these allergic reactions to COVID vaccines, with a higher rate of allergic reactions than seen with the influenza vaccine.  Despite this observation, these reactions are rare, and the risks of allergic reactions or other negative outcomes are heavily outweighed by the benefits of vaccination.  If you scroll down the page in the link above, you will see that many people had swelling of the lips as a reaction to the vaccine, and other symptoms consistent with an allergic reaction.  This is far from “proof” that the lip swelling in the patients that had lip filler had an allergic reaction instead of a reaction to their filler, but does demonstrate that there are more cases of lip swelling associated with allergic reactions than swelling of fillers (which number 2 or 3 as of this update).

Update 1/21/2021

The CDC issued an update to address this issue, and recommended “no additional precautions” in patients getting a COVID vaccine that have had facial fillers in the past.  See the full recommendations here.