Blisters - What causes them?

Blisters are usually caused by burns or friction. The burn or friction damages the skin, and the layers that make up the skin separate, leaving a gap between them. This gap then fills up with a fluid called serum. As the burn or damaged skin heals, new skin grows underneath the blister, the serum is reabsorbed and the outer layers of skin peel away.

Some viral infections including chickenpox and shingles can cause blisters, and blisters can also arise with skin conditions such as eczema and impetigo.

For more in depth advice on blisters caused by burns, see Burns & scalds.

This information does not replace medical advice. If you are concerned you might have a medical problem please ask your Boots pharmacy team in your local Boots store, or see your doctor.