Important update: Healthcare facilities
CDC has updated select ways to operate healthcare systems effectively in response to COVID-19 vaccination. Learn more
UPDATE
Given new evidence on the B.1.617.2 (Delta) variant, CDC has updated the guidance for fully vaccinated people. CDC recommends universal indoor masking for all teachers, staff, students, and visitors to K-12 schools, regardless of vaccination status. Children should return to full-time in-person learning in the fall with layered prevention strategies in place.
UPDATE
The White House announced that vaccines will be required for international travelers coming into the United States, with an effective date of November 8, 2021. For purposes of entry into the United States, vaccines accepted will include FDA approved or authorized and WHO Emergency Use Listing vaccines. More information is available here.

Allergic Reactions after COVID-19 Vaccination

Allergic Reactions after COVID-19 Vaccination
Updated Dec. 14, 2023

If You Are Having a Severe Allergic Reaction to a COVID-19 Vaccine Now

Severe allergic reactions to vaccines are rare but can happen. If you get a COVID-19 vaccine and you think you might be having a severe allergic reaction after leaving the vaccination provider site, seek immediate medical care by calling 911.

A severe allergic reaction can cause:

  • difficulty breathing or wheezing,
  • a drop in blood pressure,
  • swelling of the tongue or throat, or
  • a generalized rash or hives, which may include mucus membranes.

If You Had a Severe Allergic Reaction to a COVID-19 Vaccine in the Past

If you had a severe allergic reaction after receiving a particular type of COVID-19 vaccine (either mRNA or Novavax), you should not get another dose of that type of vaccine. You will likely be able to receive the alternate vaccine type. Your doctor may refer you to an allergy and immunology specialist for additional care or advice.

Types of COVID-19 vaccines:

If You Had a Non-severe Allergic Reaction to a COVID-19 Vaccine in the Past

If you had an allergic reaction to a COVID-19 vaccine that started within 4 hours of getting vaccinated, but the reaction was not considered severe by a medical professional, you likely can receive another dose of the same type of COVID-19 vaccine under certain conditions, such as being observed in the clinic for 30 minutes after vaccination. Your doctor may refer you to an allergy and immunology specialist for additional care or advice.

If You Have Had an Allergic Reaction to Other Vaccines, Injectables, Medications

In most cases, you will likely be able to receive a COVID-19 vaccine. All allergies should be discussed with your doctor or vaccine provider before receiving a vaccine.

  • If you had a severe allergic reaction to an ingredient used in one type of COVID-19 vaccine, you may be able to get the other type of COVID-19 vaccine.
  • If you had a non-severe allergic reaction to an ingredient used in the COVID-19 vaccine, your doctor may still recommend being vaccinated under certain conditions.

Your doctor is your best source of information if you might have an allergy to an ingredient that’s used in COVID-19 vaccines. Your doctor may refer you to an allergy and immunology specialist for additional care or advice.

If You Had a Rash on the Arm Where You Got a COVID-19 Shot

If you had a red, itchy, swollen, or painful rash where you got a COVID-19 shot, you should still get another shot at the scheduled date and time. This applies to the updated (2023–2024 formula) COVID-19 vaccine.

These rashes can start a few days to more than a week after your shot and are sometimes quite large. These rashes are also known as “COVID arm.” Tell your vaccination provider that you experienced a rash or “COVID arm” after your previous shot. Your vaccination provider may recommend that you get your next COVID-19 vaccine in the opposite arm if possible.

If the rash is itchy, you can take an antihistamine. If it is painful, you can take a pain medication like acetaminophen or a non-steroidal anti-inflammatory drug (NSAID).

Safeguards Are in Place

  • Everyone who gets a COVID-19 vaccine may be monitored onsite for at least 15 minutes after vaccination.
  • Some people may be monitored for 30 minutes after vaccination including in the following situations:
    • You had an immediate (within 4 hours) allergic reaction that was not severe from a previous dose of that type of COVID-19 vaccine.
    • You’ve had a non-severe allergic reaction to an ingredient used in the COVID-19 vaccine.

Vaccination providers should have appropriate personnel, medications, and equipment—such as epinephrine, blood pressure monitor, and timing devices to check your pulse—at all COVID-19 vaccination provider sites.

If you experience a severe allergic reaction after getting a COVID-19 vaccine, vaccination providers can provide care rapidly and call for emergency medical services. You should continue to be monitored in a medical facility for at least several hours.

CDC Is Monitoring Reports of Severe Allergic Reactions

If someone has a severe allergic reaction after getting vaccinated, their vaccination provider may send a report to the Vaccine Adverse Event Reporting System (VAERS). VAERS is a national system that collects reports from healthcare professionals, vaccine manufacturers, and the public about adverse events that happen after vaccination. Reports of adverse events that are unexpected, appear to happen more often than expected, or have unusual patterns are followed up with specific studies.

Learn more about how CDC and federal partners are monitoring the safety of COVID-19 vaccines in the United States, including reports of selected adverse events after COVID-19 vaccination.