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Flu Vaccination Side Effects

Flu Vaccination Side Effects


Influenza (inactivated) vaccine side-effects – What are the risks from inactivated influenza vaccine?


Problems that could happen after any vaccine:

  • Brief fainting spells can happen after any medical procedure, including vaccination. Sitting or lying down for about 15 minutes can help prevent fainting, and injuries caused by a fall. Tell your doctor if you feel dizzy, or have vision changes or ringing in the ears.

  • Severe shoulder pain and reduced range of motion in the arm where a shot was given can happen, very rarely, after a vaccination.

  • Severe allergic reactions from a vaccine are very rare, estimated at less than 1 in a million doses. If one were to occur, it would usually be within a few minutes to a few hours after the vaccination.


Mild problems following inactivated flu vaccine:

  • Soreness, redness, or swelling where the shot was given

  • Hoarseness

  • Sore, red or itchy eyes

  • Cough

  • Fever

  • Aches

  • Headache

  • Itching

  • Fatigue


…If these problems occur, they usually begin soon after the shot and only last 1 or 2 days…


Moderate problems following inactivated flu vaccine:

  • Young children who get inactivated flu vaccine and pneumococcal vaccine (PCV13) at the same time may be at increased risk for seizures caused by fever. Always ask your doctor for more information and tell them if a child who is getting the flu vaccine has ever had a seizure.


Inactivated flu vaccine does not contain live flu virus, so you cannot get the flu from this vaccine.

As with any medicine, there is a very remote chance of a vaccine causing a serious injury or death and the safety of vaccines is always being monitored.


Influenza (live) vaccine side-effects – What are the risks from LAIV?


Problems that could happen after any vaccine:

  • Severe allergic reactions from a vaccine are very rare, estimated at less than 1 in a million doses. If one were to occur, it would usually be within a few minutes to a few hours after the vaccination.


Mild problems that have been reported following LAIV:

Children and adolescents 2-17 years of age:

  • runny nose, nasal congestion or cough

  • fever

  • headache and muscle aches

  • wheezing

  • abdominal pain or occasional vomiting or diarrhoea


Adults 18-49 years of age:

  • runny nose or nasal congestion

  • sore throat

  • cough, chills, tiredness/weakness

  • headache


LAIV is made from weakened virus and does not cause flu.