Blisters

Blisters are a skin complaint usually caused by a combination of friction and pressure. They can be painful and appear as a small pocket filled with fluid on the surface of the skin. The purpose of the pocket is to protect the skin beneath from further injury and to speed up recovery. 


What causes blisters? 

Blisters occur around areas that are most frequently exposed to pressure, meaning they generally occur on the ankles and feet. Blisters are commonly caused by: 

• Friction

• Heat or abrasive substances that damage the skin

• Certain conditions, such as some types of eczema

• Certain infectious conditions, like chickenpox

Blisters are also more likely to form if you walk or run for extended periods of time, walk or run in uncomfortable shoes, or have a condition that causes reduced sensation (feeling) in your feet such as diabetes.


What do blisters look like? 

A blister is a pocket of fluid that forms when the outer layers of the skin separate and fill with serum, the liquid part of blood that contains protective antibodies. 

The blister forms a bubble, which may turn red if a blood vessel bleeds into it. In rare cases, a blister may become infected. Signs of infection include increased pain, redness, fever, swelling and pus on or around the blister. If you suspect your blister is infected, visit your GP who may prescribe antibiotics.


How can you treat blisters at home? 

Most blisters will heal on their own. Blister fluids will gradually be re-absorbed as the skin underneath heals. You can protect the blister, help prevent infection, and lessen pain with home treatments, such as: 

• Ensuring the area is dry and clean

• Wearing socks inside your shoes

• Eliminating the cause by wearing different shoes

• Applying a protective dressing to the area. Ask your pharmacist about suitable plasters or dressings. They may recommend hydrocolloid dressings, which can help with the healing process

As a general rule, avoid popping or bursting your blisters. It creates a hole in the skin which can leave the area underneath open to infection.

If you have a blister that’s already burst, make sure you leave the fluid in the blister to drain, and then wash it with mild soap and water. Dry the area and cover with a sterile dressing or plaster to help protect it from infection whilst it heals. 

If you have diabetes and develop a blister, make sure you visit your GP if it doesn’t heal quickly.


When should you visit a GP or podiatrist? 

If you think your blister has become infected, you should consult your GP. Other reasons to visit your GP or podiatrist include:  

• If the blister is causing extreme pain or is recurring

• If you have developed multiple blisters for no obvious reason

• If the blister is in an unusual place, such as your eyelids or genitals

• If the blister was caused by an allergic reaction, burn or sunburn


How can you help to prevent blisters? 

Blisters form to cushion damaged skin and help it heal. If you regularly get friction blisters, you can help to prevent them by:  

• Wearing shoes that are the correct size and are comfortable

• Gradually building up how much you wear new shoes

• Wearing thick socks during exercise, such as specialist sports socks

• Using protective gloves if you use tools at work or for physical activities


Next steps

• If you have a blister, use at-home remedies to treat it, such as keeping the area dry and applying a dressing. Ask your pharmacist for advice and for suitable products

• If the area gets infected or if blisters appear in unusual places, visit your GP for advice