The Moderna COVID-19 (2023-2024 Formula) (COVID-19 Vaccine, mRNA) is a vaccine that may help your body develop immunity to SARS-CoV-2, the virus that causes COVID-19. The Moderna COVID-19  vaccine is an FDA-approved vaccine for adults and adolescents aged 12 years and also has emergency use authorization (EUA) for children aged 6 months to 11 years.

This updated vaccine contains spike proteins for the XBB.1.5 sublineage of SARS-CoV-2 and trials have shown it elicits robust immune responses across multiple XBB sublineages including XBB.1.5, XBB.1.16, and also against EG.5, FL.1.5.1, and BA.2.86. Vaccination with the Moderna COVID-19 Vaccine may not protect all people who receive the vaccine.

For individuals previously vaccinated with any COVID-19 vaccine, the dose of the Moderna COVID-19 Vaccine should be administered at least 2 months after the last dose of the COVID-19 vaccine.

The Moderna COVID-19 Vaccine (2023-2024 Formula) was FDA-approved and granted EUA on September 11, 2023.

Contraindicated in people who have had a severe allergic reaction (such as anaphylaxis) to any component of the Moderna COVID-19 Vaccine.

Postmarketing data has revealed there is an increased risk of myocarditis and pericarditis, particularly within the first week following vaccination. The highest observed risk for the Moderna COVID-19 Vaccine is in males aged 18 years through 24 years of age.

Immunocompromised persons, including individuals receiving immunosuppressive therapy, may have less of a response to the Moderna COVID-19 Vaccine.

The Moderna COVID-19 Vaccine is given as an injection into the muscle, usually the deltoid muscle of the arm.

A single dose is 0.5 mL.

For individuals previously vaccinated with any COVID-19 vaccine, the dose of the Moderna COVID-19 Vaccine should be administered at least 2 months after the last dose of the COVID-19 vaccine.

You should not receive the Moderna COVID-19 Vaccine if you have had:

• a severe allergic reaction to a previous dose of the Moderna COVID-19 Vaccine (also called Spikevax) or any of the components of the vaccine (see below 'What are the ingredients in the Moderna COVID-19 Vaccine?').

There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to the Moderna COVID-19 Vaccine during pregnancy and women should enroll by calling 1-866-MODERNA (1-866-663-3762).

There is insufficient data to inform vaccine-associated risks in pregnancy, but animal studies have revealed no evidence of harm to the fetus. Pregnant women infected with SARS-CoV-2 are at increased risk of severe COVID-19 compared with non-pregnant women.

It is not known whether the Moderna COVID-19 Vaccine is excreted in human milk or its effects on the breastfed infant or milk production/excretion. Consider the benefits versus the risks.

Safety and effectiveness have not been established in children less than 12 years of age. Evidence from clinical studies strongly suggests that a single dose of the Moderna COVID-19 Vaccine is ineffective in individuals younger than 2 years of age.

What should I tell my healthcare provider?

Tell your healthcare provider about all your medical conditions, including if you:

• have any allergies
• had a severe allergic reaction after receiving a previous dose of any COVID-19 vaccine
• 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 immune system
• are pregnant or plan to become pregnant
• are breastfeeding
• have received any other COVID-19 vaccine
• have ever fainted in association with an injection.

Be sure to receive all recommended doses of COVID-19 vaccine or you may not be fully protected. Contact your vaccination provider or health department if you miss your second dose.

An overdose of Moderna COVID-19 Vaccine is unlikely to occur.

Avoid receiving other vaccines without first seeking medical advice.

Severe allergic reactions have occurred in some people who have received the Moderna COVID-19 Vaccine(also called Spikevax). There is a very small chance that the Moderna COVID-19 Vaccine could cause a severe allergic reaction. A severe allergic reaction would usually occur within a few minutes to one hour after getting a dose of the Moderna COVID-19 Vaccine. For this reason, your healthcare provider may ask you to stay for a short time at the place where you received your vaccine.

Signs of a severe allergic reaction can include:

• Difficulty breathing
• Swelling of your face and throat
• A fast heartbeat
• A rash all over your body
• Dizziness and weakness.

Myocarditis (inflammation of the heart muscle) and pericarditis (inflammation of the lining outside the heart) have occurred in some people who have received the Moderna COVID-19 Vaccine (also called Spikevax), more commonly in males aged 18 years through 24 years of age than among females and older males. In most of these people, symptoms began within a week of the Moderna COVID-19 vaccination. The chance of this happening is very low. You should seek medical attention right away if you have any of the following symptoms after receiving the Moderna COVID-19 vaccine:

• Chest pain
• Shortness of breath
• Feelings of having a fast-beating, fluttering, or pounding heart.

The most common side effects reported with the Moderna COVID-19 Vaccine include:

• Pain at the injection site (up to 91%)
• Fatigue (up to 58%)
• Headache (up to 56%)
• Muscle pain (up to 40%)
• Chills (up to 30%)
• Under the armpit swelling/tenderness (up to 28%)
• Joint pain (up to 24%)
• Nausea/vomiting (up to 18%)
• Swelling at the injection site (up to 13%).

Side effects that have been reported during post-authorization use of the vaccine include:

• Severe allergic reactions
• Myocarditis (inflammation of the heart muscle)
• Pericarditis (inflammation of the lining outside the heart)
• Fainting in association with injection of the vaccine.

These may not be all the possible side effects of the Moderna COVID-19 Vaccine. Ask your healthcare provider about any side effects that concern you. You may report side effects to the Vaccine Adverse Event Reporting System (VAERS) at 1-800-822-7967 or https://vaers.hhs.gov

Tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Tell your healthcare provider if you take:

• a blood thinner
• a medicine that affects your immune system.

Also, tell your healthcare provider if you have received any other COVID-19 vaccines.