Blisters are very common. In fact, you’ve probably experienced one if you’ve ever worn new shoes that have rubbed your feet. It is a raised pocket of skin (like a bubble) that is filled with a watery fluid.

They’re not usually serious, often won’t need medical attention and most will heal on their own.

If the blister becomes infected, if it is particularly painful, or if it has been caused by a burn or allergic reaction, you should see a GP.

Why do I get blisters?

Blisters usually develop when the skin is damaged by continuous friction, such as shoes rubbing on the skin, or pressure.

The upper layer of skin that is damaged separates from the layers underneath, allowing fluid to collect in the space that’s been The created, to protect the wound from further damage.

A blister can be uncomfortable as it heals, but it will usually get better within a week if left alone.

Symptoms of blisters include:

  • A bubble or clear fluid filled lump just under the skin
  • If there has been damage to blood vessels, the blister may contain blood
  • Itchy red spot or irritated skin in the affected area
  • Pain or discomfort

If the blister becomes infected there may be pus present.

An infected blister, or severe one can cause further complications. If you notice these symptoms you should see a doctor:

  • Increased pain or swelling
  • Pus
  • Warmth around the blister
  • Red streaks around the blister
  • Fever

Most commonly, blisters are caused by friction, a burn, or because of an allergic reaction to something.

However, there are some conditions that can cause blisters to develop, these include:

Cold sores

These little blisters are caused by a virus called herpes and develop around the mouth or on the lips.


Chickenpox is most common in children and it causes itchy blisters to form on the skin. Other symptoms include loss of appetite, aches and pains and a fever.


This is caused by the same virus as chickenpox, but is more common in grown ups. Small blisters can develop as a result.


This condition is very common and should be treated as soon as possible to stop it spreading. Scabies is caused by a tiny mite and causes a rash across the body to develop. In small children, these may blister.


This can cause blisters to form inside your mouth.

Pompholyx and other types of eczema

This is a type of eczema that cause skin irritation and blisters. Other types of eczema can also cause blisters to form.

Genital Herpes

This is a sexually transmitted infection that can cause blisters on the genitals.

Contact dermatitis

This is caused by an irritant, such a latex or chemicals, and can cause the area of skin that has come into contact with it to blister.


This is a bacterial infection of the skin that can cause it to blister.

This is not an extensive list - other conditions can lead to blisters. See a GP if you are worried, particularly if they are widespread and not healing, as there are some rare blistering skin diseases.

As we’ve mentioned, most blisters will not usually need medical attention, but if you are worried about a blister, or if you have the below symptoms, you should see a GP.

Our GPs can take a look at your blister over video consultations and recommend your next steps and whether any treatment is required. If more investigation is needed, the GP can refer you to a specialist, or for tests.

Most blisters can be taken care of at home. Do not be tempted to burst the blister yourself as you run the risk of infection, which may need to be treated by antibiotics. If your blister becomes infected, see a GP.

If the blister bursts itself, let the fluid drain away and try to keep the area clean to prevent infection - you can cover it with a plaster or sterile dressing until it is healed.

If your blister is caused by another condition, such as those mentioned above, the condition itself may need to be treated, which in turn should help the blisters heal. A doctor will be able to advise further.

If you’re worried about a blister, you can see one of GPs. They can take a look at the affected area over a video call and recommend whether you need treatment. Book an appointment today.

Skin Care Article