COVID-19 Vaccine, mRNA

Why get vaccinated?

COVID-19, mRNA vaccine can prevent COVID-19 disease or lower risk of serious illness.

COVID-19, mRNA vaccine does not contain Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2; the virus responsible for causing COVID-19 disease). The vaccine works by getting the body's cells to produce a piece of the virus that will stimulate antibodies prepared to fight the virus if exposed.

There are many variants of the COVID-19 virus and the vaccine will need to be reformulated periodically to cover the current circulating variants.

How is COVID-19, mRNA vaccine given?

COVID-19, mRNA vaccine comes as a suspension (liquid) to be given intramuscularly (into a muscle) by a healthcare provider.

For patients 2 years of age and older, it is given as single dose for the season. It should be given at least two months after receiving any dose of any COVID-19 vaccine. If you are receiving the low dose COVID-19, mRNA vaccine (mNEXSPIKE®), you will need to wait at least 3 months after receiving any other COVID-19 vaccine.

For children 6 months to 2 years of age, your healthcare provider will determine how many doses your child needs and the schedule to receive them.

What should you tell the person who is giving the vaccine?

Before receiving COVID-19 Vaccine, mRNA:

• tell your doctor if you are allergic to this vaccine, any part of this vaccine, or any medications, foods or substances. Tell your doctor or pharmacist about the allergy and what symptoms you had.

• tell your doctor if you have or have had myocarditis (inflammation of the heart muscle) or pericarditis (inflammation of the lining outside the heart), a bleeding disorder or are taking a blood thinner, a weakened immune system or are on a medicine that affects your immune system.

• tell your doctor if you have a fever or feeling unwell on day of administration.

• tell your doctor if have ever received any another COVID-19 vaccine.

• have ever fainted in association with an injection.

• tell your doctor if you are pregnant or are breast-feeding. Safety of COVID-19 vaccine, mRNA during pregnancy is not known but COVID-19 infection can have adverse outcomes during pregnancy. Pregnant patients should talk to their doctors about risks and benefits of receiving a COVID-19, mRNA vaccine during pregnancy

In some cases, your health care provider may decide to postpone COVID-19 vaccine, mRNA to a future visit.

Your health care provider can give you more information.

What are the risks from COVID-19, mRNA vaccine?

Side effects that have been reported with the COVID-19 vaccine, mRNA include:

• non-severe allergic reactions such as rash, itching, or hives

• injection site pain, swelling, and redness or arm pain

• tiredness

• headache

• muscle pain

• chills

• joint pain

• fever

• nausea

• feeling unwell

• swollen lymph nodes

• decreased appetite

• diarrhea

• vomiting

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately or get emergency medical treatment:

• difficulty breathing; swelling of face or throat; fast heartbeat; rash; dizziness or weakness

You should know that COVID-19, mRNA vaccine may increase risk of myocarditis or pericarditis (inflammation of the heart muscle or lining of the heart). Symptoms most commonly occur in the week following vaccination and is more commonly seen in males 12 to 24 years of age. Seek emergency medical treatment if you experience any of the following: chest pain; shortness of breath; feelings of having a fast-beating, fluttering or pounding heart

People sometimes faint after medical procedures, including vaccination. Tell your provider if you feel dizzy or have vision changes or ringing in the ears.

Adverse reactions should be reported to the Vaccine Adverse Event Reporting System (VAERS). Your health care provider will usually file this report, or you can do it yourself. Visit the VAERS website at https://vaers.hhs.gov or call 1-800-822-7967. VAERS is only for reporting reactions, and VAERS staff members do not give medical advice.

How can I learn more?

• Ask your healthcare provider.

• Call your local or state health department.

• Visit the website of the Food and Drug Administration (FDA) for vaccine package inserts and additional information at www.fda.gov/vaccines-blood-biologics/vaccines.

• Contact the Centers for Disease Control and Prevention (CDC): Call 1-800-232-4636 (1-800-CDC-INFO) or visit CDC's website.

Brand Names:

• Comirnaty®

• Spikevax®

• mNEXSPIKE®

Other Names: Pfizer Bio-NTech Covid-19 Vaccine; Moderna COVID-19 Vaccine

This report on medications is for your information only, and is not considered individual patient advice. Because of the changing nature of drug information, please consult your physician or pharmacist about specific clinical use.

The American Society of Health-System Pharmacists, Inc. represents that the information provided hereunder was formulated with a reasonable standard of care, and in conformity with professional standards in the field. The American Society of Health-System Pharmacists, Inc. makes no representations or warranties, express or implied, including, but not limited to, any implied warranty of merchantability and/or fitness for a particular purpose, with respect to such information and specifically disclaims all such warranties. Users are advised that decisions regarding drug therapy are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and the information is provided for informational purposes only. The entire monograph for a drug should be reviewed for a thorough understanding of the drug's actions, uses and side effects. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information is not a substitute for medical care.

AHFS® Patient Medication Information™. © Copyright, 2025. The American Society of Health-System Pharmacists®, 4500 East-West Highway, Suite 900, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.

Selected Revisions: October 15, 2025.