Emergency advice


  1. Don’t burst it.
  2. Wash around the blister and pat dry, and then cover it with a plaster.

What are blisters?

Blisters are fluid-filled bumps that look like bubbles on the skin. They usually form when someone’s skin repeatedly rubs against something or is exposed to heat. When someone gets a blister, the part of the skin that is damaged leaks fluid that collects under the top layer of the skin, forming the blister. 

What to do

  1. If someone has a blister, don’t burst it as this can increase the risk of infection. Wash the skin around the blister with clean water and gently pat the skin dry with a sterile gauze pad or a clean, non-fluffy cloth. 

    • If you cannot wash the area, try to keep it as clean as possible. 
  2. If the blister was caused by something rubbing against the skin, cover it with a plaster but make sure the pad on the plaster is larger than the blister area. Ideally use a special blister plaster, as these have a cushioned pad that gives extra protection. 

Browse our first aid products:



Shop now

Related first aid advice


Sunburn is caused by over exposure to the sun, or a sunlamp or sunbed. Find out what to look for and what to do.

How to apply a dressing

When you have a wound, you should always cover it with a dressing as this can help to prevent infection. Find out what to do.

Minor burns and scalds in adults

If someone receives a burn or scald, your priority is to cool the burn as quickly as possible. Find out what to look for and what to do.

St John Ambulance volunteers providing support