A blister is a small sac of fluid that forms on an area of the body. These bubbles can vary in size and can occur for different reasons. You’re probably familiar with blisters if you’ve ever worn ill-fitting shoes too long.


The common cause of blistering produces vesicles when friction between your skin and the shoes results in layers of skin separating and filling with fluid.

A blister is a small pocket of fluid that forms on an area of the body. These bubbles can vary in size and can occur for different reasons. You may develop one after a skin burn, infection with fungus or bacteria, an insect bite, or trauma. Depending on its location, a blister can interfere with normal, everyday tasks. For example, if you have a blister on your feet, you may have difficulty walking, exercising, or standing for long periods of time.

Of course, not everyone who walks or stands for long periods develops blisters. In many instances, these fluid-filled bubbles result from poorly fitted shoes. Shoes that fit too tightly or too loosely can rub against the skin. This causes friction, and as a result, fluid builds up underneath the upper layer of skin.

Excessive moisture or perspiration can also trigger these skin bubbles. This is common during warm seasons among athletes, particularly runners. Tiny blisters form when sweat clogs the pores in the feet.


Preventing blisters on your feet involves addressing the underlying cause. If you develop a blister due to friction, wearing properly fitted shoes is the first line of defense. If your feet rub along a specific area of your shoe, wearing an insole may provide extra padding and reduce friction.

  1. Orthotic insoles can reduce the friction caused by poor biomechanics
  2. If you’re an athlete, make sure you keep your feet dry. Apply foot powder to reduce sweating, or wear moisture-wicking socks designed for athletes. These socks dry faster and reduce moisture.
  3. Moisture-wicking socks.
  4. Padding/protection