Blister Anatomy

Understanding foot blisters

Blisters are small swelling of the skin that contains watery fluid. They are caused by friction. The body responds to the friction by producing fluid. The fluid builds up beneath the part of the skin being rubbed, causing pressure and pain. Blisters occur when feet get hot, sweaty and socks stick to the feet. The sock and foot then rub against each other and the inside of the shoe. Fluid fills up a space between layers of skin to protect the area, like a small balloon.

Blisters are a common problem with athletes wearing in new shoes. They are also a common problem for athletes, runners and walkers who participate in exceptionally long events such as marathons or long endurance walks. If a blister is red, leaking yellow fluid or has red lines near the blister, visit a doctor immediately. Redness and leaking yellow fluid are symptoms of infection.

What Causes Foot Blisters?

There are many different causes of foot blisters. Some of the most common causes of foot blisters are:

• Heat, moisture and friction.
• Friction forces caused by inappropriate shoes or socks.
• Fungal infections of the skin.
• Excessive foot perspiration.

Preventing Foot Blisters...

Some ways to prevent blisters are:

• Wear shoes that fit properly.
• Make sure that your shoes are worn in - it is best not to wear new shoes for an event.
• Keep feet as dry as possible.
• Wearing wet shoes, boots and socks will increase your chance of developing blisters.
• Change socks regularly.
• Wear proper fitted shoes.
• Choose moisture-wicking socks (socks that draw sweat away from your feet) or change socks twice daily if you have sweaty feet, as wet socks cause friction and rubbing.
• Wear ‘sports socks’ when exercising or playing sports.
• If you become aware of a localised ‘hot’ area on your foot, stop your sport and tape the area immediately.
• Apply a foot spray deodorant to reduce sweating and thereby reduce the risk of fungal infection.
• Change damp socks promptly, as wet socks can drag against the skin.

Treatments for Foot Blisters

If the blister has not "popped," it is best to leave it alone. The majority of the time, the blister will reabsorb and heal on its own.

Self-help options

Blisters rarely need medical attention, unless they are severe, recurrent, caused by burns or indicative of an underlying infection. Suggestions on treating a simple friction blister yourself include:

• Resist the temptation to burst the blister. You could cause an infection or hinder your body’s healing process.
• If the blister has burst, don’t peel off the baggy skin pocket – let your body heal the area in its own way and in its own time.
• Frequently wash the area with salt water and keep it free from dirt or irritants.
• If the site of the blister makes it vulnerable to popping (for example, a blister on your foot may be broken by the friction of socks or shoes), pad it with a soft dressing, securely taped.
• Don’t use tape alone, as removing the tape may rip the skin off the blister.
• Change the dressing daily.
• Zinc cream may help to dry up your blister. However, don’t use zinc cream with a dressing.
• If the blister breaks, press gently to remove the fluid and apply an antiseptic (such as iodine) to reduce the risks of infection.
  
  

Seek medical attention

See your doctor or other health professional for treatment if:

• The blister starts weeping pus.
• The area becomes increasingly swollen or inflamed.