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Safety profile across vaccines

Side effects in patients receiving Moderna COVID-19 Vaccine or bivalent vaccine in clinical trials

The Bivalent safety data shown here were from another Moderna bivalent vaccine, but are relevant to the authorized version of the Moderna COVID-19 Vaccine, Bivalent because these vaccines are manufactured using the same process.

Individuals may not be protected until 14 days after their second dose. As with all vaccines, vaccination with Moderna COVID-19 Vaccine and Moderna COVID-19 Vaccine, Bivalent may not protect all vaccine recipients.

Injection site side effects in patients receiving Moderna COVID-19 Vaccine or bivalent vaccine in clinical trials

The Bivalent safety data shown here were from another Moderna bivalent vaccine, but are relevant to the authorized version of the Moderna COVID-19 Vaccine, Bivalent because these vaccines are manufactured using the same process.

Individuals may not be protected until 14 days after their second dose. As with all vaccines, vaccination with Moderna COVID-19 Vaccine and Moderna COVID-19 Vaccine, Bivalent may not protect all vaccine recipients.

Warnings and Precautions

Who should not get these vaccines?

Any adult or child who:

  • had a severe allergic reaction after a previous dose of these vaccines

  • had a severe allergic reaction to any ingredient in these vaccines

What are the risks of these vaccines?

Severe allergic reactions: there is a remote chance that these vaccines could cause a severe allergic reaction. A severe allergic reaction would usually happen within a few minutes to one hour after getting a dose of the vaccine. Signs of a severe allergic reaction can include:

  • Difficulty breathing

  • Swelling of your face and throat

  • A fast heartbeat

  • A bad rash all over your body

  • Dizziness and weakness

Myocarditis (inflammation of the heart muscle) and pericarditis (inflammation of the lining outside the heart) have happened in some people who have received the vaccines, most commonly in adult males under 40. The chance of this happening is very low. Seek medical attention right away if you or your child has any of the following symptoms after receiving the vaccine:

  • Chest pain

  • Shortness of breath

  • Feelings of having a fast-beating, fluttering, or pounding heart

  • Fainting

  • Unusual and persistent irritability

  • Unusual and persistent poor feeding

  • Unusual and persistent fatigue or lack of energy

  • Persistent vomiting

  • Persistent pain in the abdomen

  • Unusual and persistent cool, pale skin

What should I do about side effects?

If you or your child experience a severe allergic reaction, call 9-1-1, or go to the nearest hospital. Call the vaccination provider or healthcare provider if you or your child have any side effects that bother you or do not go away. Report vaccine side effects to FDA/CDC Vaccine Adverse Event Reporting System (VAERS). The VAERS toll-free number is 1-800-822-7967 or report online to https://vaers.hhs.gov/reportevent.html. Please include either “Moderna COVID-19 Vaccine EUA,” or “Moderna COVID-19, Bivalent EUA” as appropriate, in the first line of box #18 of the report form. In addition, you can report side effects to ModernaTX, Inc. at https://report.moderna.convergehealthsafety.com. You may also be given an option to enroll in V-safe. V-safe is a new voluntary smartphone-based tool 
that uses text messaging and web surveys to check in with people who have been vaccinated to identify potential side effects after COVID-19 vaccination. V-safe asks questions that help the CDC monitor the safety of COVID-19 vaccines. V-safe also provides second-dose reminders if needed and live telephone follow-up by the CDC if participants report a significant health impact following COVID-19 vaccination. For more information on how to sign up, visit: https://www.cdc.gov/vsafe. Side effects with medications and vaccines such as the Moderna COVID-19 Vaccine, Bivalent. All healthcare professionals are asked to 
report any suspected adverse reactions via the national reporting system and include batch/lot number 
if available.

Frequently Asked Questions

We have answers in the FAQ section.

IMPORTANT SAFETY INFORMATION

AUTHORIZED USE

  • Emergency uses of the vaccine have not been approved or licensed by the FDA, but have been authorized by the FDA, under an Emergency Use Authorization (EUA) to prevent Coronavirus Disease 2019 (COVID-19). The Moderna COVID-19 Vaccine is authorized in individuals 6 months of age and older as a primary series. The Moderna COVID-19 Vaccine, Bivalent is authorized as a booster dose in individuals 6 months through 5 years of age at least 2 months after the Moderna COVID-19 Vaccine primary series and is authorized in individuals 6 years of age and older at least 2 months after any authorized or approved vaccine.

  • The EUA for these products is in effect for the duration of the COVID-19 EUA declaration justifying emergency use of the product, unless the declaration is terminated or the authorization is revoked sooner.

  • For more information on the EUA authorized uses of the vaccine, refer to the Vaccine Fact Sheets for Recipients and Caregivers.

What should you mention to the vaccination provider before you or your child gets these vaccines? Tell your vaccination provider about all medical conditions, including if you or your child:

  • have any allergies

  • have had myocarditis (inflammation of the heart muscle) or pericarditis (inflammation of the lining outside the heart)

  • have a fever

  • have a bleeding disorder or are on a blood thinner

  • are immunocompromised or are on a medicine that affects your or your child’s immune system

  • are pregnant or plan to become pregnant

  • are breastfeeding

  • have received another COVID-19 vaccine

  • have ever fainted in association with an injection

Who should not get these vaccines? Any adult or child who:

  • had a severe allergic reaction after a previous dose of these vaccines

  • had a severe allergic reaction to any ingredient in these vaccines

What are the risks of these vaccines? Severe allergic reactions: there is a remote chance that these vaccines could cause a severe allergic reaction. A severe allergic reaction would usually happen within a few minutes to one hour after getting a dose of the vaccine. Signs of a severe allergic reaction can include:

  • Difficulty breathing

  • Swelling of your face and throat

  • A fast heartbeat

  • A bad rash all over your body

  • Dizziness and weakness

Myocarditis (inflammation of the heart muscle) and pericarditis (inflammation of the lining outside the heart) have happened in some people who have received the vaccines, most commonly in adult males under 40. The chance of this happening is very low. Seek medical attention right away if you or your child has any of the following symptoms after receiving the vaccine:

  • Chest pain

  • Shortness of breath

  • Feelings of having a fast-beating, fluttering, or pounding heart

  • Fainting

  • Unusual and persistent irritability

  • Unusual and persistent poor feeding

  • Unusual and persistent fatigue or lack of energy

  • Persistent vomiting

  • Persistent pain in the abdomen

  • Unusual and persistent cool, pale skin

Side effects that have been reported in clinical trials with these vaccines include:

  • Injection site reactions: pain, tenderness and swelling of the lymph nodes in the same arm of the injection or in the groin, swelling (hardness), and redness

  • General side effects: fatigue, headache, muscle pain, joint pain, chills, nausea and vomiting, fever, rash, irritability/crying, sleepiness, and loss of appetite

These may not be all the possible side effects of these vaccines. Serious and unexpected side effects may occur. The possible side effects of these vaccines are still being studied in clinical trials.

What should I do about side effects? If you or your child experience a severe allergic reaction, call 9-1-1, or go to the nearest hospital.

Call the vaccination provider or healthcare provider if you or your child have any side effects that bother you or do not go away.

Report vaccine side effects to FDA/CDC Vaccine Adverse Event Reporting System (VAERS). The VAERS toll-free number is 1-800-822-7967 or report online to https://vaers.hhs.gov/reportevent.html. Please include “Moderna COVID-19 Vaccine EUA,” or “Moderna COVID-19, Bivalent EUA” as appropriate, in the first line of box #18 of the report form.

In addition, you can report side effects to ModernaTX, Inc. at 1-866-MODERNA (1-866-663-3762).

Please see the Vaccine Fact Sheets for Recipients and Caregivers for more information: