What should you know about an influenza injection?

The injection uses non-infectious influenza material to prompt an immune response. Influenza viruses change over time, so vaccination is planned for the strains expected in a season and may be recommended again in a later season. The injection cannot give you influenza. It may not prevent every respiratory infection, but it is intended to lower the chance of severe flu and related problems such as pneumonia.

Tell the vaccinator about a previous serious reaction, a severe allergy, or an illness you have today. After the injection, soreness in the arm, tiredness, headache, chills, or a mild fever can occur and generally settle with time. Follow the clinic's advice about comfort measures and normal activity. If you develop influenza symptoms, rest, drink fluids, and ask about testing or treatment when you are at higher risk of complications. Explore Influenza, Fever, Cough, and Fatigue for related information.

Call emergency services for difficulty breathing, swelling of the lips or throat, fainting, or a rapidly spreading rash after vaccination. Seek prompt medical care for chest pain, confusion, severe weakness, blue lips, or breathing that is becoming harder during a flu-like illness. A cough with worsening breathlessness or persistent fever needs assessment because influenza can be followed by pneumonia.

Ask whether vaccination is suitable with your health conditions, which seasonal formulation is offered, and what to do if you miss the clinic appointment. Ask how to distinguish an expected local reaction from symptoms needing review.