Blisters are small pockets of fluid that form over damaged skin to form a bubble, protecting the damaged skin, and allowing it to heal. They require immediate first aid treatment to prevent further damage to the skin and to ensure the blister does not become infected.
Most blisters contain a clear fluid called serum which protects the underlying skin. Some contain blood as per the name ‘blood blister’. In more serious cases they may contain a yellow or green pus which is a sign of infection, which can lead to further complications such as sepsis, when left untreated.


  • Hot / warm spot on feet / hands
  • White bump that may form into a bubble on the skin
  • Red mark, whereby raw skin has been exposed
Hint - the above mainly focuses on the hand / feet but sunburn can affect any area of the body. 


  • Don’t burst the blister - increases the risk of infection
  • Gently wash the area around the blister with clean water, using gauze pad or a non-fluffy cloth
Helpful hint - Cotton wool and other similar products are fluffy, can stick to the skin, and irritate it.

  • Next apply a special blister plaster which allows the skin to heal underneath.
Helpful hint - The blister plaster can be left on until it naturally falls off, or peels away.

  • When you don’t have a blister plaster you can use a normal plaster, but make sure the pad covers the blistered area.

The above treatment protocol is useful on walks, hikes and runs where you may need to continue the activity. In more serious cases , or in the absence of having blister plasters you may need to cease the activity that you are doing. Where possible, change into open-ended footwear such as sandals or flip flops. Keep the blistered area clean and allow natural air to heal it over several days.

When to get help?

The above treatment protocol is not suitable for sunburn. In these cases seek medical attention if the blistered area covers more than 1% of the body’s surface.
Helpful hint - The palm of your hand equates to around 1% of your body’s surface. Use this as a rough measurement without touching the affected area.

It is necessary to seek medical attention if the blister is showing signs of being infected (yellow / green pus). When left untreated it can lead to secondary impetigo, which is a contagious, bacterial infection. Further complications include cellulitis, and even sepsis, which is potentially life threatening when left untreated.