A blister is a fluid-filled vesicle (or sac) that forms on the skin’s surface. It is a common condition that can occur due to various reasons, such as friction, burns, or allergic reactions. They can also be a symptom of certain medical conditions, such as chickenpox, shingles, or herpes.
One study found that blisters affect approximately 39% of the general population, with the highest incidence occurring in athletes and military personnel. Blisters can occur on any body part but are most commonly found on the feet, followed by the hands and fingers. Foot blisters are a common problem, with an estimated 39% to 82% of marathon runners experiencing blisters during a race.
What is a Blister?
A blister forms beneath the skin’s surface. The fluid inside a blister is usually clear or yellowish and consists of serum, which is the liquid portion of blood. They can be painful and may cause discomfort, especially in areas constantly subjected to pressure or friction, such as the feet or hands. (1)
Blisters can be caused by various factors, including friction, heat, cold, chemical exposure, and medical conditions such as herpes and eczema. People with conditions that affect circulation or nerve function in the feet – such as diabetes and peripheral neuropathy – are at higher risk of developing blisters and complications. Rarely, blisters can signify more serious medical conditions, such as autoimmune diseases or infections.