'Blisters are usually caused by injury to the skin from heat or from friction, which create a tear between the epidermis—the upper layer of the skin—and the layers beneath. When this happens, the surface of the skin remains intact, but is pushed outwards as serum seeps into the newly created space between the layers.
Short periods of intense rubbing can cause a blister, but any rubbing of the skin at all can cause a blister if it is continued for long enough. Blisters are most common on the hands and feet, as these extremities are susceptible while walking, running, or performing repetitive motions. Blisters form more easily on moist skin than on dry or soaked skin, and are more common in warm conditions.
Sometimes, the skin can blister when it comes into contact with a cosmetic, detergent, solvent or other chemical; this is known as contact dermatitis. Blisters can also develop as a result of an allergic reaction to an insect bite or sting.'
Most blisters heal naturally and do not require medical attention. As new skin grows beneath the blister, the fluid contained within it will be slowly reabsorbed by the body and the skin on top will dry and peel off.
The unbroken skin over a blister provides a natural barrier to infection. This means that you should try to keep blisters intact and unbroken in order to avoid infection. Try not to pierce a blister with a needle, but allow it to break on its own once the skin underneath has healed.
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