7 mins read

Overview: Measles/mumps/rubella (MMR) vaccine is used to prevent measles, mumps, and rubella. It works by using weakened forms of virus to trigger the body’s immune response to make a type of protein (antibodies) that helps protect against these infections. Common side effects include pain, redness, and swelling near the injection site, irritability, loss of appetite, drowsiness, and fever. MMR vaccine is injected into a muscle or under the skin by a health care provider.

Uses

What is MMR vaccine used for?

Measles/mumps/rubella (MMR) vaccine is commonly used to prevent measles, mumps, and rubella.

  • Measles (M), also known as rubeola, is a contagious viral infection. It causes cough, runny nose, fever, and a full-body rash. It can lead to diarrhea, seizures, ear infections, and pneumonia. In rare cases, measles can cause brain damage or death.
  • Mumps (M) is also a contagious viral infection. It causes fever, headache, tiredness, muscle aches, loss of appetite, and swollen, tender glands under the ears. Mumps can lead to serious complications including deafness, brain swelling, and, in rare cases, cause death.
  • Rubella (R) is a contagious viral infection that causes fever, sore throat, rash, eye irritation, and headache. It can cause arthritis in up to half of teenage and adult women. In pregnant women, rubella can cause a miscarriage or serious birth defects in the baby.

How does MMR vaccine work (mechanism of action)?

MMR vaccine is a live vaccine that contains weakened forms of the measles, mumps, and rubella viruses. It triggers the body’s immune response to make a type of protein (antibodies) that helps protect against these infections. 

How should I store MMR vaccine?

MMR vaccine is usually given by a pharmacist or other health care provider in a pharmacy, hospital, or clinic. You will not store it at home.

Side Effects

What are the most common side effects of MMR vaccine?

The most common side effects of MMR vaccine are listed below. These side effects may vary depending on the MMR vaccine product used and the person’s age. Tell your health care provider if you have any of these side effects that bother you.

  • Pain, redness, and swelling near the injection site
  • Irritability
  • Loss of appetite
  • Drowsiness
  • Fever

There may be other side effects of MMR vaccine that are not listed here. Contact your health care provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088 (800-332-1088). In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of MMR vaccine?

While less common, the most serious side effects of MMR vaccine are described below, along with what to do if they happen.

Severe Allergic Reactions. MMR vaccine may cause allergic reactions, which can be serious. Get emergency help right away if you have any of the following symptoms of a serious allergic reaction.

  • Breathing problems or wheezing
  • Racing heart
  • Fever or general ill feeling
  • Swollen lymph nodes
  • Swelling of the face, lips, mouth, tongue, or throat
  • Trouble swallowing or throat tightness
  • Itching, skin rash, or pale red bumps on the skin called hives
  • Nausea or vomiting
  • Dizziness, feeling lightheaded, or fainting
  • Stomach cramps
  • Joint pain

Febrile Seizure. MMR vaccine can cause you to have a febrile seizure, which is a seizure caused or triggered by a fever. Symptoms may include convulsions (full body shaking and twitching), fever of 100.4 F (38 C) or more, eye rolling, moaning, not responding, losing control of the bladder or bowels, and a bleeding mouth or tongue. If a febrile seizure happens, move your child to a safe place, such as the floor, so they can’t fall. Roll your child on the side to avoid choking. If the seizure lasts less than a few minutes and your child is breathing and stable, call the child’s health care provider. Call 911 and get emergency help if any of the following symptoms happen. 

  • Seizure lasts more than five minutes
  • Struggling to breathe or turning blue
  • Only one part of the body is twitching
  • Odd behavior for an hour or more after the seizure
  • Another seizure happens within 24 hours 

Severely Low Platelet Levels. MMR vaccine can cause you to have a severely low number of platelets in your blood, also called thrombocytopenia. Platelets help to form blood clots. Having a low level of platelets may increase your risk of bleeding. Tell your health care provider if you have any of the following symptoms of low platelet levels.

  • Easy bruising or bleeding
  • Bleeding that does not stop
  • Nosebleeds

Thrombotic Thrombocytopenic Purpura (TTP). MMR vaccine can lead to a serious problem with blood clotting, called TTP. TTP is when blood clots form in some parts of your bloodstream, which causes a loss of platelets in the rest of the blood (thrombocytopenia). TTP needs to be treated right away in the hospital or it can lead to death. Get emergency help if you have any of the following symptoms without another explanation.

  • Fever
  • Shortness of breath
  • Pale or yellowish skin
  • Your skin or the whites of your eyes turning yellowish (also called jaundice)
  • Changes in your vision
  • Unusual weakness or tiredness
  • Headache, confusion, or slurred speech
  • Fast heartbeat
  • Purplish spots (purpura) on the skin or in the mouth due to bleeding under the skin
  • Low amount of pee or pee that is pink or has blood in it

Warnings & Precautions

Who should not use MMR vaccine?

Allergies to Ingredients. People who are allergic to any of the following should not receive MMR vaccine.

  • Gelatin 
  • M-M-R II
  • Measles, mumps, and rubella vaccine, live
  • MMR
  • Neomycin
  • Priorix
  • Any of the ingredients in the specific product received

Your pharmacist or other health care provider can tell you all of the ingredients in the specific MMR vaccine products they stock.

Weak Immune System. MMR vaccine should not be used if you have a weak immune system (including primary immunodeficiency or secondary immunodeficiency), get infections easily, or take medicines or treatments that suppress the immune system (such as radiation or chemotherapy).

Pregnancy. MMR vaccine should not be used if you are pregnant or plan to get pregnant within the next month. 

Fever. MMR vaccine should not be used if you have a fever of more than 101.3 F (38.5 C). You should wait until you recover from illness before getting the MMR vaccine.

Tuberculosis. MMR vaccine should not be used if you currently have a tuberculosis infection. 

What should I know about MMR vaccine before using it?

MMR vaccine is given on a specific schedule. Follow all vaccine recommendations given by your health care provider.

The risk of dizziness or fainting, which may lead to a fall, is the highest within a few minutes after receiving MMR vaccine. Your health care provider may want to watch you for this time to ensure your safety.

MMR vaccine may affect the results of the tuberculin skin test, a test used to check for tuberculosis. For accurate results, the tuberculin skin test should be done either before receiving the MMR vaccine, at the same time, or at least four to six weeks after receiving the vaccine.

What should I tell my health care provider before using MMR vaccine?

Tell your health care provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them determine if MMR vaccine is right for you.

In particular, make sure that you discuss any of the following.

Current and Past Health Conditions. Tell your health care provider if you have any of the following.

  • Fever or recent illness, including tuberculosis
  • A reaction to a previous vaccine (MMR, MMRV, or other), including fainting or Guillain-Barré Syndrome
  • A weak immune system, get infections easily, or take medicines or treatments that suppress the immune system (such as radiation or chemotherapy)
  • Anyone in your household or family (parent or sibling) with a weak immune system or immune system problems
  • Low platelet levels (thrombocytopenia)
  • Seizures or a family history of seizures, including febrile seizures
  • Received blood or plasma transfusions or human serum globulin

Vaccines. Talk with your health care provider about any vaccines that you may need. You should not receive live vaccines right before or right after receiving MMR vaccine. Tell your health care provider about any vaccines you have recently received or have scheduled.

Egg Allergy. Tell your health care provider if you are allergic to eggs. People with an egg allergy may have a higher risk of having a reaction to MMR vaccine.

Latex Allergy. MMR vaccine syringes may contain natural rubber latex. Tell your health care provider if you are allergic to latex or rubber.

Other Medicines and Supplements. MMR vaccine may interact with other medicines and supplements. Before receiving MMR vaccine, tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. See the Interactions section for more details.

Pregnancy. MMR vaccine should not be used during pregnancy. You should avoid getting pregnant for one month after receiving MMR vaccine. Call your health care provider if you were exposed to MMR vaccine during pregnancy or in the month before becoming pregnant.

Breastfeeding. It is not known if MMR vaccine passes into breast milk. Tell your health care provider if you are breastfeeding or plan to breastfeed. Your health care provider will let you know if you should receive MMR vaccine while breastfeeding.

Interactions

Does MMR vaccine interact with foods or drinks?

There are no known interactions between MMR vaccine and foods or drinks.

It is unknown if drinking alcohol will affect MMR vaccine.

Does MMR vaccine interact with other medicines (drug interactions)?

Always tell your health care provider about all recent and upcoming vaccines, any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.

In particular, make sure that you discuss if you are using any of the following before using MMR vaccine.

  • Any medicines or treatments that suppress the immune system, such as radiation, chemotherapy, or a corticosteroid, which is a medicine for certain inflammatory conditions
  • Immune globulin or any other blood product or transfusion

This may not be a complete list of medicines that can interact with MMR vaccine. Always check with your health care provider.

Does interact with other drugs you are taking?

Enter your medication into the WebMD interaction checker

Overdose/Missed Dose

What should I do if I accidentally use too much MMR vaccine?

If you or someone else has used too much MMR vaccine, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.

What should I do if I miss a dose of MMR vaccine?

If you miss an appointment for MMR vaccine, call to make another appointment as soon as possible. It is important to follow the vaccine schedule recommended by your health care provider.