The COVID-19 vaccines are finally here. And while they signify hope for so many people, others aren’t so enthusiastic about getting them. Among those who might be in the skeptical camp are people who have allergies.
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For those who are managing allergies daily, it can be a little worrisome to hear that some people have experienced allergic reactions after receiving the COVID-19 vaccine, especially if they have a history of severe reactions themselves. If you’re in this boat, you might feel like you should give the COVID-19 vaccine a hard pass. But David M. Lang, MD, allergist and Chair of Cleveland Clinic’s Department of Allergy and Clinical Immunology, has a few reasons for why you shouldn’t.
What we know so far about allergic reactions to COVID-19 vaccines
The FDA has issued emergency use authorization for three COVID-19 vaccines. The Pfizer-BioNTech vaccine, which has been recommended by the CDC for people age 16 and older, is 95% effective at preventing COVID-19 illness according to clinical trial results. The Moderna vaccine, which has been suggested by the CDC for people age 18 and older, is 94.1% effective.
A third vaccine, produced by Johnson & Johnson via Janssen Pharmaceutical Companies, was just recently approved for an Emergency Use Authorization by the FDA. In clinical trials, this vaccine was shown to be 66% effective in preventing moderate and severe COVID-19 disease 28 days after vaccination. Overall, the vaccine was also 85% effective in preventing hospitalization and 100% effective in preventing death, 28 days after vaccination.
The CDC has since reported that between Dec. 14 and Dec. 23, 2020, there were 21 cases of anaphylaxis after the administration of a reported 1,893,360 first doses of the Pfizer-BioNTech COVID-19 vaccine (11.1 cases per million doses). Of these cases, 71% of these occurred within 15 minutes of vaccination.
“Even though there is a risk of anaphylaxis, it’s still very small — and the potential benefit from the COVID-19 vaccination clearly exceeds the potential for harm,” says Dr. Lang. “The situation is evolving, however, and we’ll learn more as we gain more experience with these vaccines.”
For the Johnson & Johnson vaccine, of the nearly 22,000 study participants who received the vaccine, five patients reported developing hives within a week. There was one case of what was considered severe “a hypersensitivity reaction,” but it was reportedly not related to anaphylaxis.
Reasons to avoid the vaccine
It’s recommended that if you’ve had an allergic reaction any of the ingredients in the vaccine, you should not get it. If you had an allergic reaction to the first dose of a COVID-19 vaccine, the CDC doesn’t recommend getting the second dose. But overall, having allergies doesn’t exclude you from getting the vaccine.
What ingredients are in the vaccines?
Here’s a breakdown of what’s in the three COVID-19 vaccines that have been approved for emergency use.
Pfizer BioNTech’s COVID-19 vaccine ingredients
According to Pfizer, the Pfizer BioNTech COVID-19 vaccine is a messenger RNA (mRNA) vaccine was made with synthetic and chemically produced components as well as enzymatically produced components from naturally occurring substances like proteins. This vaccine does not have a live virus in it.
Inactive ingredients in the Pfizer BioNTech COVID-19 vaccine include:
- Potassium chloride.
- Monobasic potassium.
- Sodium chloride.
- Dibasic sodium phosphate dehydrate.
- Sucrose (sugar).
- Small amounts of other ingredients.
Moderna’s COVID-19 vaccine ingredients
Moderna’s vaccine is similar to Pfizer BioNTech’s and also has no live virus in it. Its ingredients include:
- Messenger ribonucleic acid (mRNA).
- Lipids, or fatty substances, including: SM(sphyngomyelin)-102, Polyethylene glycol [PEG] 2000 dimyristoyl glycerol [DMG], 1,2-distearoyl-sn-glycero-3-phosphocholine [DSPC], and cholesterol.
- Tromethamine hydrochloride.
- Acetic acid.
- Sodium acetate.
- Sucrose (sugar).
Johnson & Johnson’s COVID-19 vaccine ingredients
Unlike the other vaccines, the Johnson & Johnson vaccine is a single-dose viral vector vaccine, which uses an adenovirus (the kind of virus that typically causes colds) to harmlessly deliver the DNA code into your cells. Besides those virus particles, the ingredients of this vaccine include:
- Sodium chloride.
- Citric acid monohydrate.
- Trisodium citrate dihydrate.
What could be causing allergic reactions
“It’s believed that COVID-19-related allergic reactions are related to polyethylene glycol (PEG), an ingredient in the vaccines,” says Dr. Lang. Whether some of the reactions are occurring via another mechanism is unclear at this time.
How vaccination myths can cause hesitation
It’s understandable that hearing about allergic reactions to COVID-19 vaccines can make people slightly uneasy. Dr. Lang believes educating patients on the infrequency of adverse reactions and the truth about common vaccination myths can help put more people at ease.
“Many times, patients claim they got sick from a vaccine, when they’re really referring to a natural immune response from the vaccine,” he says. “Fever, chills and muscle aches can occur within 36 hours of vaccination because a patient’s immune system is responding appropriately in developing immunity after receiving the vaccine. It’s not an allergic reaction.”
He adds that delayed reactions due to immune response, as well as fatigue, soreness at the injection site and vasovagal reactions(drop in blood pressure, fainting episodes), are not cause for avoiding COVID-19 vaccines. This is especially important to keep in mind if a reaction occurs after the first dose of the two-dose COVID-19 vaccination regimen.
Guidelines for administering the vaccine
As mentioned before, only those with a known allergy to PEG or another vaccine ingredient should consider not getting vaccinated for COVID-19. And if you have an allergic reaction after the first shot, you shouldn’t get the second shot.
If you’ve had a severe allergic reaction to another vaccine or injectable medication — or have experienced anaphylaxis from any cause — you can still receive the COVID-19 vaccine. However, your vaccination should be followed by a 30-minute observation period in a setting where personnel, equipment and supplies are present to manage anaphylaxis if needed.
“Anaphylaxis commonly occurs within 30 minutes of exposure and would be unusual after 60 minutes,” says Dr. Lang.
Patients with allergies to other medications, foods or inhalants can receive the COVID-19 vaccine with normal precautions. This typically includes a 15-minute observation period after the injection based on CDC guidelines
Again, if you have questions about COVID-19 vaccines or aren’t quite sure about what you should do, talk to your doctor.