NEWS

Experts: COVID-19 Vaccines Safe For People With Existing Allergies

An older blonde white woman with black glasses and a gray-olive face mask getting a band aid stuck on her arm by a healthcare worker wearing a paper face mask.

CDC/Unsplash

Key Takeaways

  • Severe allergic reactions to the mRNA COVID-19 vaccines (including Pfizer and Moderna) are rare, but research has shown that they are different from other classic food and drug allergies.
  • Most people with multiple existing allergies can safely receive the Pfizer or Moderna COVID-19 vaccines, but to be on the safe side, they should discuss their options with an allergy specialist beforehand.
  • The majority of people who have an allergic reaction to the first dose of the Pfizer or Moderna vaccine can safely receive their second dose, but experts say that they should also consult an allergy specialist.

If you have multiple allergies or have experienced an allergic reaction to a medication or vaccine in the past, you might be wondering if you can safely receive a COVID-19 vaccine and if so, which one you should get.

In response to questions and concerns about allergies, researchers at Sheba Medical Center in Ramat Gan, Israel, and Israel’s Ministry of Health, conducted research to determine the best practices for immunizing people with a high risk of allergic reactions to the COVID-19 vaccine.

Their findings, as well as advice from other experts, suggests it's safe for most people with allergies to get vaccinated.

COVID-19 Vaccines and Allergies

  • According to recent research, there are approximately 4.7 cases of anaphylaxis for every 1 million doses of the COVID-19 vaccine given.
  • Among the people who have experienced anaphylaxis after receiving the Pfizer vaccine, 81% reported having previous allergies, and 90% were female.

Evaluating 'Highly Allergic' Patients

For the study, which was published in The Journal of the American Medical Association in August, researchers at Sheba Medical Center reviewed data from 8,102 patients with allergies from December 27, 2020, to February 22, 2021. The patients were either self-referred or directed to the research center by a doctor.

The researchers identified 429 people among those referred to the study as being “highly allergic" because they met the following criteria:

  • A prior anaphylactic reaction to any drug or vaccine
  • Multiple drug allergies
  • Multiple allergies
  • Food allergies
  • Regular use of antihistamines
  • Carry an adrenaline syringe

All of the patients in the study received the BNT162b2 (Pfizer) vaccine, which was the most widely available in Israel at the time. However, study author Nancy Agmon-Levin, MD, says that the same principles apply to the Moderna vaccine.

Experts recommend that highly allergic patients receive a COVID-19 vaccine under medical supervision.

How Many Patients Had Reactions?

Of the 429 high-risk patients who received their first dose of the Pfizer vaccine under medical supervision:

  • 420 experienced no immediate allergic reaction
  • 6 developed minor allergic reactions
  • 3 experienced anaphylaxis

The researchers gave a second dose of the Pfizer vaccine to 218 of the 429 high-risk patients. Of those patients:

  • 214 did not have any allergic reaction
  • 4 experienced minor allergic reactions
  • None experienced anaphylaxis

While the data from the study mirrored the findings of Pfizer's Phase 3 clinical trial, its cohort included a higher percentage of women (70%) than the Pfizer trial (just under 50%), because there is an overall higher incidence of allergic reactions in women.

How Are Vaccine Allergies Different?

Any drug or vaccine has the potential to cause an allergic reaction, but Agmon-Levin says that allergic reactions to the mRNA vaccines for COVID-19 appear to be different from classic allergies.

“Allergic reactions can occur via many pathways,” says Agmon-Levin. “True allergies are medicated by an immunoglobulin called Ig-E. All these can cause a severe, immediate reaction."

The Role of Ig-E

According to Agmon-Levin, "once you have experienced the reaction, exposure to a minimal amount of the allergen—even an accidental exposure—can cause a very severe allergic reaction. That’s why you are told to never consume the allergen again."

This type of reaction is what Agmon-Levin says is called "a true allergy.”

The COVID-19 mRNA vaccines reactions appear to be caused by mechanisms other than Ig-E, which is probably why they can often be tolerated after a previous allergic reaction. It also means that most people are not experiencing a true allergy.

“We have defined two different reactions to the mRNA COVID vaccine," says Agmon-Levin. "One of them can cause Ig-E mediated hypersensitivity. Once this is suspected, then a true allergy is suspected, and a vaccine should be avoided. But this is very rare."

Nancy Agmon-Levin, MD

Allergies are very common. If you’ve ever had an allergy, you should get immunized like everyone else.

— Nancy Agmon-Levin, MD

According to Agmon-Levin, "the vast majority of patients that have some other sort of reaction will not be mediated via Ig-E and in that case, re-exposure is recommended, and that we can manage easily.”

During the Sheba Medical Center trial, patients who were found to have an Ig-E-related reaction to the Pfizer vaccine did not receive a second dose. Those who had other types of allergic responses received medications to manage their symptoms.

“The adverse events are very minimal and easy to overcome,” says Agmon-Levin. “For those who had some sort of allergic-like reaction, they can use antihistamines, but it’s important to notice that it is not needed for the vast majority of patients.”

Getting Vaccinated Safely

Another study—also recently published in The Journal of the American Medical Association—suggested that taking an antihistamine before getting a COVID-19 mRNA vaccine might prevent allergic reactions in some patients, but Agmon-Levin says more research is needed.

Anyone who is worried about the risk of having an allergic reaction to a vaccine should share their concerns with a healthcare provider—preferably, an allergy specialist. Consulting with an expert is particularly important for patients with severe allergies to multiple drugs and those who have had adverse reactions to other vaccines in the past (which Agmon-Levin says occurs in about 1% to 2% of patients with allergies).

Agmon-Levin recommends that people with underlying conditions such as hay fever and asthma ensure that their symptoms are well-controlled before receiving a vaccine. Agmon-Levin and the study co-authors also advised that patients wait a few days to one week after receiving any allergy injections to get a COVID vaccine.

The bottom line is one that cannot be stated often enough: vaccination is safe and effective for most people.

“Patients with mild allergic reactions can safely be immunized for a second time with medication," says Agmon-Levin. "And a general practitioner or allergy specialist can recommend what you can take prior to vaccination.”

Is the Johnson & Johnson Vaccine a Safe Alternative?

The authors of the study say that “it has been suggested that the polyethylene glycol (PEG) used to construct the nanoparticle-encapsulated lipid of this vaccine is a possible candidate."

Agmon-Levin says that people who are allergic to GoLYTELY—a common laxative used prior to colonoscopies—might be more predisposed to PEG allergies.

The Pfizer and Moderna mRNA vaccines contain PEG, but the Johnson & Johnson vaccine does not. People with allergies might prefer to get the J&J shot to minimize their risk of a reaction. 

Risks of Avoiding Vaccination

Agmon-Levin warns that putting off or skipping COVID-19 vaccination is dangerous—especially for patients with underlying allergies.

“Allergies are very common. If you’ve ever had an allergy, you should get immunized like everyone else," says Agmon-Levin. "You might get a rash, or you might have some coughing. This will be uncomfortable, but it will go away within a few hours whereas COVID can kill you. It is the best choice 99.9% of the time.”

Kenneth L. Campbell, DBE, MPH, MBA, MA, Clinical Assistant Professor & Program Director of MHA (Online) in the Department of Health Policy and Management at Tulane University School of Public Health and Tropical Medicine, tells Verywell that both vaccines are safe for people who have had a reaction to the first dose and that these people have "done much better with the second dosage of Pfizer and/or Moderna" according to recent studies.

COVID has affected everyone, but not everyone has been affected equally. Still, Campbell says that "all communities, especially minority communities, should feel very safe taking these vaccines, for it adds another layer of protection from getting COVID-19."

If you're still worried, bring up your concerns with your doctor. "We want to be cognizant that people are getting the right information," says Cambell. "You don’t have to decide alone.”

What This Means For You

If you have a history of prior allergies, adverse reactions to medications and vaccines, or had a reaction to your first dose of an mRNA COVID-19 vaccine, it does not mean that you cannot safely receive both doses of the COVID-19 vaccine.

If you are worried about getting your shot, talk to your healthcare providers—preferably, an allergy specialist. While it's likely safe for you to get vaccinated, there might be some steps you can take to minimize any discomfort you could experience if you have a mild reaction.

The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.

Was this page helpful?
3 Sources
Verywell Health 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. Shavit R, Maoz-Segal R, Iancovici-Kidon M, et al. Prevalence of Allergic Reactions After Pfizer-BioNTech COVID-19 Vaccination Among Adults With High Allergy RiskJAMA Netw Open. 2021;4(8):e2122255. doi:10.1001/jamanetworkopen.2021.22255

  2. Centers for Disease Control and Prevention. Allergic Reactions Including Anaphylaxis After Receipt of the First Dose of Pfizer-BioNTech COVID-19 Vaccine — United States, December 14–23, 2020. MMWR Morbidity and Mortality Weekly Report. 2021;70.

  3. Krantz MS, Kwah JH, Stone CA Jr, et al. Safety Evaluation of the Second Dose of Messenger RNA COVID-19 Vaccines in Patients With Immediate Reactions to the First DoseJAMA Internal Medicine. Published online July 26, 2021. doi:10.1001/jamainternmed.2021.3779