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Many people have no side effects from COVID-19 vaccines. If you do have side effects, they tend to be mild and go away in a few days. Common side effects may include:
What should I do if I have side effects?
Call Health Link at 811 to report any serious or unusual side effects. It’s rare to have a serious side effect.
Between 4 and 28 days after getting the Janssen vaccine, there have been very rare reports of blood clots, low levels of platelets (these help your blood to clot), and bleeding.
If you have any of the following symptoms within 42 days of being immunized, get medical help right away:
There have been very rare reports of capillary leak syndrome (CLS) within the first few days after getting the Janssen vaccine. CLS is a serious condition that causes sudden swelling of the arms and legs, sudden weight gain, and low blood pressure causing you to feel faint. Get medical help right away if you have any of these symptoms.
There have been very rare reports of Guillain-Barre syndrome (GBS) up to 42 days after getting the Janssen vaccine. GBS is a serious condition that causes pain or numbness, muscle weakness, and, in severe cases, paralysis. Get medical help right away if you have any of these symptoms.
In the first 7 days after getting the Pfizer-BioNTech, Moderna, or Novavax vaccines, there have been very rare reports of myocarditis (inflammation of the heart muscle) and pericarditis (inflammation of the lining around the heart). This inflammation can cause shortness of breath, chest pain or pressure, or a very fast or abnormal heart rate. Get medical help right away if you have any of these symptoms.
Some of the side effects from COVID-19 vaccines are the same as COVID-19 symptoms, such as fever and shortness of breath. Fever is a common side effect after a vaccine. Shortness of breath is rare.
If you have a fever or shortness of breath that start within 24 hours of getting your vaccine, you need to stay home and away from others (isolate). If you have shortness of breath, you should also get medical attention right away. If these symptoms go away within 48 hours, you don’t have to keep isolating unless you were told to isolate for other reasons.
If your fever or shortness of breath start after 24 hours or last longer than 48 hours, or you have other symptoms such as cough, sore throat, or runny nose, you need to isolate. If you have these symptoms:
If you have an at-home COVID-19 rapid test, use it. Go to alberta.ca/rapidtesting to find out what to do next depending on your rapid test result.
If you only have redness, swelling, or soreness where you had the needle, you don’t need to isolate.
To help with soreness and swelling:
If you have a fever, wear fewer layers of clothes and drink more fluids. There is medicine to help with a fever or pain. Check with your doctor or pharmacist if you aren’t sure what medicine or dose to take. Follow the directions on the package. Children under the age of 18 years should not take aspirin because it can cause serious health problems.
Some people with health problems, such as a weak immune system, must call their doctor if they get a fever. If you were told to do this, call your doctor even if you think the fever is from the vaccine.
It’s still important to follow the recommended public health measures to prevent the spread of COVID-19, even if you’ve had a COVID-19 vaccine. Visit ahs.ca/covid for the most up-to-date recommendations.
Go to MyHealth.Alberta.ca/myhealthrecords for your COVID-19 immunization record. You can also sign up for a MyHealth Records account to get a list of most immunizations you’ve had in Alberta.
To see this information online and learn more, visit MyHealth.Alberta.ca/health/pages/conditions.aspx?Hwid=custom.ab_imm_covid19vaccine_ac.
For 24/7 nurse advice and general health information call Health Link at 811.
Current as of: May 12, 2022
Author: Provincial Immunization Program, Alberta Health Services
This material is not a substitute for the advice of a qualified health professional. This material is intended for general information only and is provided on an "as is", "where is" basis. Although reasonable efforts were made to confirm the accuracy of the information, Alberta Health Services does not make any representation or warranty, express, implied or statutory, as to the accuracy, reliability, completeness, applicability or fitness for a particular purpose of such information. Alberta Health Services expressly disclaims all liability for the use of these materials, and for any claims, actions, demands or suits arising from such use.