What is a blister?

A blister is a bump on the skin containing fluid. Blisters are usually circular in shape. The fluid that forms underneath the skin can be bloody or clear.

What causes a blister?

Blisters are caused by injury, allergic reactions, or infections, which may include the following:

  • Burns/scalds
  • Sunburns
  • Friction (from a shoe, for example)
  • Contact dermatitis
  • Impetigo (a contagious infection of the skin)
  • Viral infections (including chickenpox and herpes zoster)

The symptoms of a blister may resemble other skin conditions or medical problems. Always consult your child's physician for a diagnosis.

First-aid for blisters:

Blisters often heal spontaneously. Treatment will vary according to the cause. Some general guidelines for treatment may include:

  • Wash the area with soap and water
  • A cold or ice pack may help reduce swelling and discomfort
  • Keep the area clean and dry - do not burst or puncture the blister
  • If the blister bursts, place an adhesive bandage or dressing on the area to keep it clean
  • Observe the area for signs of infection such as increased warmth, swelling, redness, drainage, pus formation, or pain. If you notice any signs of infection, call your child's physician--antibiotics may be needed.