Most people who receive vaccines have minimal or no side effects, although, as with any medicine, adverse reactions can occur. The most common side effects are injection site pain, swelling, redness; headache; stomach and digestive complaints (e.g., nausea, vomiting, diarrhea and/or stomach pain); muscle or joint pain; tiredness; headache and chills/fever.
Should you develop any of the following symptoms or allergic reactions, seek medical attention right away. Symptoms of an allergic reaction or severe side effects include:
- Hives
- Swelling of the face, tongue or throat
- Difficulty breathing, hoarseness or wheezing
- High fever (over 40°C or 104°F)
- Convulsions or seizures
Please report any side effects or severe vaccine reaction to your physician or local health public health unit. If you experience a severe allergic reaction, call 911 or go to the nearest hospital.
You should talk to your primary health provider about known side effects from the vaccine vs. serious adverse reactions.
For TeamUHN and hospital collaborative health care workers:
Any post-vaccine symptoms that are the same as COVID symptoms require employees to follow hospital policies for reporting COVID symptoms. Please check with your organization and follow the appropriate processes. For TeamUHN, find our
reporting COVID symptoms process on the Intranet.
(Corporate Intranet > COVID-19 Updates > Health and Safety > Health Services COVID-19 Screening for Staff)
Yes. If you are experiencing any side effects such as fever, headache, chills or fatigue, you should remain off work and go to an assessment centre for testing. Please
click here to find a testing centre near you.
If you have a vaccine scheduled for less than 7 days before your surgery, you may want to reschedule your vaccine. Up to 15 people out of 100 may get a fever after getting a COVID-19 vaccine. If you have a fever on the day of your surgery, your surgery may be rescheduled.
Wait at least 1 week after your surgery before receiving a vaccine. Having a fever can be a sign of infection after surgery. By waiting 1 week to get the vaccine after surgery, your health care team will be able to determine if the fever is related to an infection and not a vaccine side effect.
We don't have data on these populations since they were excluded from the trials. However, expert groups have judged that for the large majority of people the benefits of the vaccine currently far outweigh any possible risks. As per the latest
Ministry of Health guidance, individuals who are pregnant, breastfeeding, or immunosuppressed may be eligible to get vaccinated.
Please note, we cannot provide medical assessments at our vaccination clinics. Questions about personal health must be reviewed with your health care provider before you arrive for your appointment.
Individuals who are pregnant — you will be asked be asked to provide verbal confirmation that you have consulted your health care provider when you arrive at the clinic.
Individuals who are breastfeeding — COVID-19 mRNA vaccines are not live vaccines and, based on their biologic mechanism of action, mRNA vaccines are not thought to be a risk to the breastfeeding infant. You will be asked to provide verbal confirmation that you are aware of the insufficiency of evidence for the use of COVID-19 vaccine in the breastfeeding population.
Individuals with autoimmune conditions, immunodeficiency conditions or those immunosuppressed due to disease/treatment that are receiving stem cell therapy, CAR-T therapy, chemotherapy, immune checkpoint inhibitors, monoclonal antibodies (e.g., rituximab) and other targeted agents (e.g., CD4/6 inhibitors, PARP inhibitors etc.) — you will be asked to provide verbal confirmation that you have consulted your treating provider when you arrive at the clinic.
All other individuals with autoimmune conditions, immunodeficiency conditions or those immunosuppressed due to disease/treatment — you are advised to have a conversation with your health care provider about the risks vs. benefits of taking the vaccine, but are not required to do so.
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Question updated: March 15, 2021
- If you have had a
severe allergic reaction or anaphylaxis to a previous dose of a COVID-19 mRNA vaccine or to any of its components, you should not receive the mRNA COVID-19 vaccine in a general vaccine clinic. An urgent referral to an allergist/immunologist is recommended, and is required to assess the method for possible (re)administration of a COVID-19 vaccine.
- If you have had
an allergic reaction within 4 hours of receiving a previous dose of an mRNA COVID-19 vaccine or any of components of the mRNA COVID-19 vaccine you should not receive either mRNA COVID-19 vaccine unless you have been evaluated by an allergist-immunologist. The components include polyethylene glycol and, due to potential cross-reactivity, polysorbate.
DOCUMENTATION – If you fall into the above categories, you will be required to present documentation of the discussion with your allergist-immunologist. It must include a vaccination care plan, confirm that appropriate counselling on the safe administration of vaccine was provided, and include the date, the clinician's name, signature and contact information as well as the individual's name and date of birth.
- If you have had
an allergic reaction within 4 hours and/or anaphylaxis that occurred with a vaccine or injectable medication that does not contain a component or cross-reacting component of the mRNA COVID-19 vaccines, you may be vaccinated, and asked to wait
30 minutes for observation after your receive your vaccine.
- If you have a history of significant allergic reactions and/or anaphylaxis to any
food, drug, venom, latex, or other allergens not related to the mRNA vaccine, you can be vaccinated with and will be asked to wait
30 minutes for observation after you receive your vaccine.
- If you have allergy issues such as
allergic rhinitis, asthma or eczema, you can be vaccinated, and will be asked to wait 15-30 minutes after your vaccine for observation.
The medicinal ingredient in both the Pfizer and Moderna Vaccine is
mRNA.
Non-Medicinal Ingredients
Pfizer COVID-19 Vaccine
- ALC-0315 = ((4-hydroxybutyl)azanediyl)bis(hexane-6,1-diyl)bis(2-hexyldecanoate)
- ALC-0159 = 2-[(polyethylene glycol)-2000]-N,N-ditetradecylacetamide
- 1,2-Distearoyl-sn-glycero-3-phosphocholine
- cholesterol
- dibasic sodium phosphate dihydrate
- monobasic potassium phosphate
- potassium chloride
- sodium chloride
- sucrose
- water for injection
View list on Health Canada website
Moderna COVID-19 Vaccine
- 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC)
- acetic acid
- cholesterol
- lipid SM-102
- polyethylene glycol (PEG) 2000 DMG
- sodium acetate
- sucrose
- tromethamine
- tromethamine hydrochloride
- water for injection
View list on Health Canada website
Question updated: April 13, 2021
This compound is commonly used in laxatives, makeup, skin care products, personal lubricants and toothpastes. It is also in cough syrup, and in some food and drinks. PEG is in the COVID-19 vaccines we offer and it has been associated with some allergic reactions from the vaccines. If you are unsure of the ingredients you are allergic to, talk to a health care provider. Please note, we cannot provide medical assessments at our vaccination clinics. Questions about personal health must be reviewed with your health care provider before you arrive for your appointment.
Page last updated: April 13, 2021