For Quebec Residents – Please click here FR

Possible Side Effects Following the Flu Shot

Side effects from the flu shot are minor. The most comon side effects are a sore arm and redness at the needle site. These are normal, temporary and have much less of an impact than if you were to get the flu.

Below are flu shot side effects and recommended actions.


  • Sore arm
  • Redness at the needle site

These are normal, don't worry.

Exercising the arm or applying a cold pack later in the day will minimize the discomfort. If necessary, take ibuprofen or acetaminophen to ease the pain.


  • Fever
  • Headache
  • Tiredness
  • Muscle soreness

Monitor. Just in case.

Symptoms may start 6-12 hours after the flu shot. If any of these symptoms do not go away in 1-2 days or get worse, see your doctor.

Extremely Rare

  • Shortness of breath
  • Tightness in chest
  • Feeling of faintness or weakness
  • Swelling of lips
  • Hives

This is a medical emergency.

If any of these symptoms occur, you could be having a severe reaction to the vaccine. This is a medical emergency! Call for help or go to the nearest emergency clinic. Remember to report any reactions to your doctor.

The information in this article is presented strictly for informational purposes only, and should not be taken as medical advice. Please see your health care provider if you have any questions about your condition, medication, or treatment.



Seasonal influenza, commonly known as the flu, is a highly contagious infection of the airways, affecting the nose, throat and lungs.

Learn More About the Flu

Book your flu shot now!

Speak with your pharmacist today.