Patient Medication Information: uses, side effects, how to take - Priorix
What PRIORIX is used for:
PRIORIX is a vaccine used for protection against measles, mumps and rubella.
How PRIORIX works:
PRIORIX protects your child against measles, mumps and rubella. It works by helping the body to make its own antibodies which protect your child against these diseases. As with all vaccines, PRIORIX may not completely protect all people who are vaccinated.
The ingredients in PRIORIX are:
Medicinal ingredient(s): Each 0.5 mL dose of the reconstituted vaccine contains not less than 103.0 CCID50 of the Schwarz measles, not less than 103.7 CCID50 of the RIT 4385 mumps, and not less than 103.0 CCID50 of the Wistar RA 27/3 rubella virus strains.
Non-medicinal ingredients: amino acids, lactose, mannitol, sorbitol and water for injection. Residue: neomycin sulphate.
PRIORIX comes in the following dosage form(s):
PRIORIX is provided as a freeze-dried vaccine for reconstitution with sterile diluent (water for injection).
Do not use PRIORIX if:
- you or your child has an infection with a high temperature.
- you think you or your child has previously had an allergic reaction to PRIORIX, neomycin (an antibiotic contained in the vaccine in trace amounts) or any other component contained in this vaccine.
Signs of an allergic reaction may include skin rash, shortness of breath and swelling of the face and tongue. If you or your child has had a skin rash (dermatitis) after treatment with neomycin, your child can still be vaccinated with PRIORIX.
- you think you or your child has previously had an allergic reaction to any vaccine against measles, mumps and rubella
you or your child’s defenses against infections (immunity mechanisms) are severely
- impaired.
you are pregnant. Furthermore, pregnancy should be avoided for one month after vaccination. Breastfeeding individuals can be vaccinated only where there is a clear need for vaccination.
- you have any severe illness or have recently received or are still taking any medicine that weakens the immune system (including high dose corticosteroids).
To help avoid side effects and ensure proper use, talk to your healthcare professional before you receive PRIORIX. Talk about any health conditions or problems you may have, including if you:
- have a high temperature (over 38°C), previous allergic reactions to this vaccine, neomycin or any ingredient in the vaccine.
- ever had a severe allergic reaction to eggs or anything that contained eggs.
- have an impaired defenses against infections or will be starting a medicine that weakens the immune system. You or your child should be closely monitored as the responses to the vaccines may not be sufficient to ensure a protection against the illness.
- or somebody else in the family has a history of convulsions or allergic diseases.
- are taking any other medicine or has recently received any other vaccine.
- have any serious health problems.
- have a condition called thrombocytopenia (decreased platelets which may lead to unusual bleeding or bruising).
- are pregnant, or breastfeeding.
As with other vaccines, appropriate medical treatment and supervision should always be readily available in case of rare anaphylactic events (severe allergic reaction that can be life threatening) following the administration of the vaccine.
Fainting can occur following, or even before, any needle injection; therefore, tell the doctor or nurse if you or your child fainted with a previous injection.
Tell your healthcare professional about all the medicines you take, including any drugs, vitamins, minerals, natural supplements or alternative medicines.
The following may interact with PRIORIX:
Vaccination should be delayed for at least three months in individuals who have received immune globulins or a blood transfusion.
If a tuberculin test (skin test to check for tuberculosis) is to be performed, it should be done either before, at the same time as, or 4 to 6 weeks after vaccination with PRIORIX, otherwise the result of the tuberculin test may not be correct.
Your doctor may decide to give PRIORIX at the same time as other vaccines. A different injection site will be used for each vaccine.
How to take PRIORIX:
The vaccine must be administered by a healthcare professional.
A single dose of the reconstituted vaccine is 0.5 mL.
Usual dose:
PRIORIX will be injected under the skin or into a muscle either in the upper arm or in the outer thigh.
PRIORIX should not be administered intravascularly (into a blood vessel).
Different injectable vaccines should always be administered at different injection sites.
PRIORIX may be given as a booster dose in individuals who have previously been vaccinated with another measles, mumps and rubella combined vaccine.
Overdose:
If you think you, or a person you are caring for, have taken too much PRIORIX, contact a healthcare professional, hospital emergency department, regional poison control centre or Health Canada’s toll-free number, 1-844 POISON-X (1-844-764-7669) immediately, even if there are no signs or symptoms.
Missed dose:
Make sure you or your child finishes the complete vaccination course. If not, you or your child may not be fully protected against infection.
Possible side effects from using PRIORIX:
These are not all the possible side effects you or your child may have when receiving PRIORIX. If you or your child experience any side effects not listed here, tell your healthcare professional.
Like all vaccines, PRIORIX may occasionally cause unwanted effects.
As with all injectable vaccines, there is a rare risk of allergic reactions. The signs of allergy may include local or widespread skin rash that may be itchy or blistering, swelling of the eyes and face, difficulty in breathing or swallowing which may lead to collapse. These reactions will usually occur before leaving the doctor’s office. However, you should seek immediate treatment in any event.
Side effects that occurred during clinical trials with PRIORIX were as follows:
Very common: ≥ 10%
- Redness at the injection site
- Fever ≥38°C (rectal) or ≥37.5°C (axillary/oral)
Common: ≥ 1% and < 10%
- Upper respiratory tract infection
- Rash
- Pain and swelling at the injection site
- Fever >39.5°C (rectal) or >39°C (axillary/oral)
Uncommon: ≥ 0.1% and < 1%
- Infection of the middle ear
- Swollen glands in the neck, armpit or groin
- Loss of appetite
- Nervousness, abnormal crying, not being able to sleep (insomnia)
- Discharge with itching of the eyes and crusty eyelids (conjunctivitis)
- Bronchitis, cough
- Swollen glands in the cheek
- Diarrhoea, vomiting
Rare: ≥ 0.01% and < 0.1%
- Allergic reactions
- Seizures with fever
After the marketing of PRIORIX, the following additional side effects have been rarely reported:
- Infection around the brain or spinal cord (meningitis)
- Measles-like symptoms
- Mumps-like symptoms (including transient, painful swelling of the testicles and swollen glands in the neck)
- Bleeding or bruising more easily than normal due to a drop in a type of blood cell called platelets, unusual bleeding or bruising under the skin
- Infection or inflammation of the brain, spinal cord and peripheral nerves resulting in temporary difficulty when walking (unsteadiness) and/or temporary loss of control of bodily movements), inflammation of some nerves, possibly with pins and needles or loss of feeling or normal movement (Guillain-Barré syndrome)
- Narrowing or blockage of blood vessels. This may include unusual bleeding or bruising under the skin (Henoch Schonlein purpura) or fever which lasts for more than five days, associated with a rash on the trunk sometimes followed by a peeling of the skin on the hands and fingers, red eyes, lips, throat and tongue (Kawasaki disease)
- Severe condition of the skin that may affect the mouth and other parts of the body
- Joint and muscle pains
If you or your child develops any other symptom within days following the vaccination, tell the doctor as soon as possible.
If you or your child have a troublesome symptom or side effect that is not listed here or becomes bad enough to interfere with your daily activities, tell your healthcare professional.
Reporting suspected side effects for vaccines
For the general public: Should you experience a side effect following immunization, please report it to your healthcare professional.
Should you require information related to the management of the side effect, please contact your healthcare professional. The Public Health Agency of Canada (PHAC), Health Canada (HC), and GlaxoSmithKline Inc. cannot provide medical advice.
For healthcare professionals: If a patient experiences a side effect following immunization, please complete the Adverse Events Following Immunization (AEFI) Form appropriate for your province/territory (Reporting Adverse Events Following Immunization (AEFI) in Canada) and send it to your local Health Unit.
Storage:
Store your vaccine in a refrigerator at 2 to 8°C.
Do not freeze.
Store in original packaging in order to protect from light.
The expiry date is shown on the label and packaging. The vaccine should not be used after this date.
Keep out of reach and sight of children.
If you want more information about PRIORIX:
- Talk to your healthcare professional
- Find the full product monograph that is prepared for healthcare professionals and includes the Patient Medication Information by visiting the Health Canada Drug Product Database website (Drug Product Database: Access the database); the manufacturer’s website www.gsk.ca; or by calling 1-800-387-7374.
Date of Authorization: 2026-02-23
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