Measles, Mumps, and Rubella (MMR) Vaccine

Brand Name(s): M-M-R® II , Priorix®

Why get vaccinated?

Measles, mumps, and rubella (MMR) vaccine may prevent measles, mumps and German measles that can occur following infections with the rubeola, paramyxovirus and rubella viruses.

Measles due to infection with rubeola virus can cause the following: fever, cough, runny nose, and red watery eyes, commonly followed by a rash that covers the whole body. It can lead to seizures (often associated with fever), ear infections, diarrhea, and pneumonia. Rarely, measles can cause brain damage or death.

Mumps due to infection with paramyxovirus virus can cause the following: fever, headache, muscle aches, tiredness, loss of appetite, and swollen and tender glands under the ears. It can lead to deafness, swelling of the brain and/or spinal cord covering, painful swelling of the testicles or ovaries, and, very rarely, death.

German measles due to infection with rubella virus can cause the following: fever, sore throat, rash, headache, and eye irritation. It can cause arthritis in teenage and adult women. If a woman gets rubella while she is pregnant, she could have a miscarriage or the baby could be born with serious birth defect.

MMR vaccine contains live viruses that have been weakened so they do not cause disease but can still stimulate the body to make antibodies against the viruses to provide a defense against potential infection.

How is the vaccine given?

MMR vaccine comes as a powder to be mixed with a liquid to be given intramuscularly (into a muscle) or subcutaneously (under the skin) by a healthcare provider.

MMR vaccine can be given as the following:

  • 2 doses, at least 4 weeks apart, ideally as 1st dose at 12 to 15 months of age and 2nd dose between 4 to 6 years of age.

  • 3 doses, if the first dose is given at less than 12 months of age, with 2nd dose at 12 to 15 months of age and 3rd dose at 3 to 6 years of age.

If MMR vaccine is given after exposure to measles, it should be given within 72 hours of being exposed to the virus.

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

Tell your vaccine provider if you:

  • have had an allergic reaction to this vaccine, any part of this vaccine, any other vaccine or any drug, food or substance. Tell your vaccine provider about the allergy and what symptoms you had.

  • have a weakened immune system or if anyone in your family has a weakened immune system

  • have a fever and any sign of infection

  • have tuberculosis

  • have a condition that makes you bruise or bleed easily

  • have had seizures or if anyone in your family has had seizures

  • have recently had a blood or plasma transfusion

  • are taking any prescription or nonprescription medications, vitamins, or nutritional supplements

  • are pregnant or planning to become pregnant. MMR vaccine is not recommended during pregnancy. You should avoid getting pregnant for 1 month after receiving the vaccine. Talk to your doctor if you have concerns about pregnancy and the vaccine.

  • are breastfeeding.

In some cases, your health care provider may decide to postpone vaccination to a future visit.

What are the risks from vaccination?

Side effects that have been reported with MMR vaccine include:

  • pain, swelling, or redness where the shot is given

  • fever

  • rash

  • irritability

  • joint pain or swelling

  • swelling of the testicles

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

  • hives, rash, wheezing, or difficulty breathing or swallowing

  • unusual bruising or bleeding

  • seizures, headache, change in behavior or consciousness, or difficulty walking

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 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?

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, 2026. 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: July 15, 2026.