Blisters are a small swelling or pocket of fluid in the upper skin layers.

They are one of the body’s responses to injury, pressure or friction. Blisters on the feet are particularly common in runners, walkers and athletes. They can be caused by:

  • Biomechanical factors

  • Ill-fitting shoes

  • Stiff shoes

  • Wrinkled socks against the skin

  • Excessive moisture 

  • Foot deformities.

Blisters occur when feet get hot, sweaty and your socks stick to them. The sock and foot rub against each other and the inside of the shoe, leading to increased friction, which causes a blister. The result is a raised lump filled with clear fluid, which may or may not contain blood and the skin will be red and tender.

Blisters rarely need medical attention unless they are severe, recurrent or occur in people at risk of foot problems such as those with diabetes.

If a blister does occur:

  • There will be a risk of infection if you pop it
  • Protect the area from pressure with an appropriate bandage (ask your pharmacist)
  • If the blister breaks, press gently to remove the fluid and apply iodine based antiseptic to reduce the risks of infection
  • Seek medical treatment if you have blisters with red, leaking yellow fluid or pus, if they are inflamed or if there are red lines near them, these may be signs of infection.

Prevention is better than cure!

  • Wear shoes that fit properly
  • Keep feet as dry as possible
  • Wear sports socks when exercising or playing sports
  • If you become aware of a localised ‘hot’ area on your foot, stop your sport and tape the area immediately
  • If you are susceptible to blisters, visit a podiatrist, they will be able to advise on appropriate footwear, protective dressings and prevention measures.

When to see Foot Matters Podiatry

Podiatrists have an important role to play in preventing and managing foot problems. Prompt action is important. Problems which are left without assessment or treatment may result in major health risks.