Flu jab side effects

The flu jab doesn't usually cause side effects. However, you may experience mild fever and slight muscle aches for a day or so.

If you have a sore arm after the vaccination, try these tips to ease the pain:

  • continue to move your arm regularly – don't let it get stiff and sore
  • use a heat pack or warm compress on the area
  • use an ice pack on the area if it becomes hot and sore – do not apply ice directly to your skin: wrap it in a towel first
  • take a painkiller, such as paracetamol or ibuprofen – do not give aspirin to children under 16

You can't catch flu after the flu jab

The flu jab cannot cause flu because there are no active viruses in the vaccine.

If you have what you think is flu after vaccination, it may be that you have caught a flu-like virus that isn't really flu, or you may have caught flu before your flu vaccination had taken effect.

Read more about what the flu jab contains.

Allergic reactions to the flu jab

Serious allergic reactions (anaphylaxis) to flu vaccines are very rare. Healthcare staff giving vaccinations are fully trained to deal with anaphylaxis and, with prompt treatment, individuals make a quick and complete recovery.

Contact a pharmacist or your GP if you experience severe side effects that are not improving over time.

Find out how to report a vaccine side effect.

Page last reviewed: 01/09/2015

Next review due: 01/09/2016


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