What are Blisters?

Blisters are small fluid filled pockets that occur in the outer layers of the skin. Although most blisters are filled with a clear fluid called serum, some are filled with blood, of if infected, can fill with puss.

Although blisters are benign in nature, they can still be very painful and if severe, can really impede mobility.

Symptoms of Blisters:

Blisters can be identified as slightly raised, soft or bouncy areas of the skin. Blisters are either identified as

• Small blisters or vesicles that measure smaller than five millimetres in diameter
• Large blisters, often called bullas. These are usually bigger than five millimetres in diameter

Whilst some blisters can be relatively painless, others can be very sore – blood blisters are very sensitive to pressure and generally more painful than serum filled blisters.

Most blisters have a cycle of around 3- 7 days depending on the severity and treatment, but generally the process of new skin growing beneath the blister, the serum drying up and the old skin peeling off takes this amount of time.

Infected blisters can last longer and are identified by their yellow or green puss. The skin around the blister will be red and feel hot and painful – infected blisters usually lead to a GP consultation.

Causes of Blisters:

Blisters regularly occur on the feet, resulting from ill fitting footwear that has caused friction and applied consistent pressure to a particular area on the foot – often the heel or small toe area. When friction occurs the surface of the skin remains intact, but a space is created in the top layers of skin that then fills with serum, that then pushes the skin out.

Other causes of blisters can be:

• Heat burn or scald
• Allergic reactions
• Sunburn
• Insect bites
• Diabetes
• Medical conditions such as chicken pox, herpes, impetigo and eczema can cause blisters

Relief and Prevention of Blisters:

Most blisters will ease within 3 days and self heal in about a week.

When you have a blister it is best to leave it alone. The skin on the top shouldn’t be broken as it is protecting the injury from infection. Gradually, the serum will be absorbed back in to the body and the top layer of skin will dry out and peel off, revealing the new skin underneath.

If the blister does burst then it should be treated in a sterile environment to lessen the risk of infection. The skin shouldn’t be peeled off and you should make an attempt to release all the fluid inside the blister, clean the wound and dress accordingly to prevent infection.

If blisters do become infected then you can consult your GP and antibiotics can be provided if necessary.

Where new footwear has caused a blister from rubbing on areas of the foot unaccustomed to pressure on that spot, it’s best to leave the shoes off until the blister heals, then gradually wear the shoes in again until the foot becomes accustomed and less sensitive in that area.