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Are there any side effects from the vaccine?

Like all medicines, vaccines can cause side effects. This is because vaccines work by making a response in your immune system. Most side effects are mild and don’t last long, and not everyone gets them. The most common side effects should only last a day or two.  

Common side effects include:  

  • a headache  
  • aching muscles, and  
  • soreness, redness or swelling at the site of the injection. 

No side effects have been reported in babies born to mothers who have been vaccinated. 

Rare or very rare side effects from the vaccine include: 

  • Guillain-Barré syndrome, a nerve condition that causes muscle weakness, and 
  • allergic reactions, such as swelling of the face, lips, tongue or throat, hives (a raised, itchy rash), difficulty swallowing, and feeling dizzy.

These symptoms may be a sign of a serious allergic reaction and typically happen within 15 minutes of being vaccinated.  Call 999 immediately if you have had the vaccine and experience any of the following.  

To find out more about the side effects of the vaccine, read the patient information leaflet online at: 

If your symptoms get worse or if you are concerned, contact NHS 111 Wales by calling 111 or contact your GP surgery. Calls to NHS 111 Wales are free from landlines and mobile phones. 

You should report suspected side effects of vaccines and medicines online at mhra.gov.uk/yellowcard (external site), by downloading the Yellow Card app, or by calling 0800 731 6789 (Monday to Friday, 9am to 5pm).