A blister is caused by friction between the skin and the inside of a shoe or clothing. Heat build up causing a swelling under the skin which may or may not have blood in it.

Treatment of blisters

Most small foot blisters should be left alone and will usually heal on their own. However if you do get a blister on a long run or walk then there are a few things you can do to ease the pain.

At the first sign of a blister

Blister plastersThe first sign of a blister there will be redness over the skin, possibly at the back of the heel, the instep or toes. This is known as a hot spot and is the early warning sign of a blister forming. Applying a second skin dressing, blister plaster or tape to the affected area can provide an additional protective layer helping to prevent the blister forming.

Ensure feet are dry and change socks. Wet socks will cause a blister much faster than dry socks. An effective but short term measure is cover the foot and affected area in petroleum jelly. This should provide some relief from pain as it protects the skin and lubricates but as the heat from the foot melts the petroleum jelly it will run away and be ineffective.

When should I pop a blister?

For larger blisters or those which are causing problems, it may be necessary to pop them. Popping blisters should be done with caution, following these guidelines.

Blister on heelMake a small hole at the edge with a sterilised pin or needle, particularly if the blister is on a weight bearing surface. A pin can be sterilised by passing it through a flame. Important, do not drain a blood filled blister. The skin is protecting the wound from infection. Clean the blister with a sterilising wipe.

Drain the fluid but leave as much of the skin as possible covering the wound. This is an important protective layer for the underlying skin and will help to prevent infected blisters. Cover the wound with a second skin or blister plaster - take the time to apply it correctly. For additional security apply tape over top.

How to get rid of blisters?

Blisters will usually just drain and heal on their own. Even if you have had to pop a blister, you should then simply clean the area, cover it to protect it and leave it to heal naturally.

Preventing blisters

Blister tapingPrevention is by far the best cure for blisters. Once you have a blister out on a long walk or during a game then it is going to cause pain and slow you down. Preventing a blister in the first place should be an easy task if you look after your feet and follow are few simple tips.


Take care of your footwear. Ensure that shoes fit correctly. Poorly fitting shoes that are either too tight or too big will increase rubbing or friction on the foot and toes. Running shoes should last 6 months or 500 miles. Change them before they become too worn out. Look after your walking boots or shoes. Do not leave them on radiators or near heaters. This may cause the leather to shrink and seams protrude.


Protect the potential hot spots by applying a second skin and / or blister taping. Use the highest quality zinc oxide tape which will stay stuck to the foot for longer especially when the feet get wet. A blister plaster is designed specifically for blisters and to act as a second skin. Make sure they are warm and the foot dry before applying them but once they are on properly they should stay in place for 24 hours and be very effective at preventing blisters.


Keep feet as dry as possible. Wet shoes, boots and socks will cause blisters far quicker than dry ones. Wherever possible change your socks regularly and use foot powder to help keep them dry.

Running and blisters

Blisters are common amongst long distance runners. All of the above can be used to help prevent developing blisters, especially taping but there are a couple of extra points which may help:

  • Introduce new running shoes gradually. It may take a couple of runs for your feet to adjust to a new pair of running shoes.
  • Some people advocate wearing socks with a double layer. The second layer stops the first one from rubbing against the skin. Others prefer a single layer loop stitched sock as less heat is generated. The important thing is to find what works best for you.
  • Try using petroleum jelly on areas prone to blisters. This helps the material glide over the skin, reducing friction. Petroleum jelly is a handy item to include in a running first aid kit. If you get a blister out on a long walk or run then smothering the area with petroleum jelly will provide temporary relief.
  • Blister taping if done properly should prevent most blister problems.

Blood blisters

Blood blisterBlood blisters are those which appear dark or red in color. This is due to damage occurring to blood vessels which bleed into the skin tissues. A blood blister tends to occur more from a sudden impact or pinching of the skin, rather than a repetitive friction.

It should be treated in the same way as a normal blister, although be aware that due to the deeper damage, the skin underneath would be raw and usually very sore and more prone to infection.