What are blisters on skin?

Blisters are dome-shaped, fluid-containing “bubbles” on the skin that form in response to skin injury, certain medical conditions, or allergies. If left intact, blisters can act as a natural dressing by protecting the skin under it from infection.

Blisters on skin form when a clear to a pale yellow fluid starts forming under the skin around the injured area. This fluid is called serum or serous fluid, and is made up of blood without any of the blood cells or clotting proteins. Our bodies releasing this fluid to cover the injured area inflates that portion of the skin but also covers up the injury and prevents it from getting an infection. Blisters are fairly easy to notice as they are swollen, sometimes inflamed spots of skin that can either be itchy, painful or both. There may also be redness surrounding the blister usually when the surrounding tissue is inflamed.

Causes of blisters on skin

There are many factors or causes that can lead to blisters on skin to form. Among them are:

Intense friction

A friction blister is caused when the skin is subjected to intense rubbing or friction of any kind for a long enough period. This intense friction can cause layers of the epidermis, the outermost layer of our skin, to separate and fill up with serous fluid. This fluid is still full of vitamins, minerals, and proteins that can help accelerate healing. This type of blister is common in athletes, construction workers, rock climbers, bodybuilders, or anyone who lives a very active lifestyle.

Intense temperatures

Serous fluid floods any area of our skin that gets damaged, including from very high or very low temperatures. When burns, usually 2nd-degree burns or worse, damage deep layers of skin, serous fluid will start filling the injured area to help heal and prevent infection.

On the other hand, intense cold can freeze the water in the cells of our skin and tissue, causing them to expand and crystalize into tiny, sharp, crystals of ice which can tear our skin and muscles. This will then make our bodies release serous fluid to patch up the wound.

Infections

Blisters can be seen in certain bacterial skin infections. For instance, blisters form when a person gets impetigo. The bacteria that causes impetigo contains proteins that cause the upper layers of the skin to separate and allow pus to accumulate inside the blisters.

Infections will cause our body to release not just serous fluid, but also antibodies like white blood cells to fight off the infection.

Intense impact or trauma

Another cause of blisters may be an injury caused by trauma, usually blunt force. Strong impact may cause the many, small blood vessels in our skin to break apart or rupture. This causes blood to leak out and in between the damaged layers of the skin. The damaged layers of the skin will allow blood to leak into it and form blood blisters.

Skin irritation or allergies

Strong chemicals that can be found in the more potent cleaners and industrial-grade disinfectants and detergents can irritate the skin. They can cause an inflammatory reaction that allows blisters to form. In people with sensitive skin, blisters can occur when there is an intense allergic reaction to a topical product or insect bite.

Medical conditions

Blisters can also form as a result of other medical condition such as eczema, herpes, chickenpox, and certain autoimmune disorders of the skin like bullous pemphigoid.

These diseases cause our bodies to release large amounts of antibodies to fight them off. Unfortunately, these diseases may damage the cells which separate the layers of the skin. These separated layers will then cause gaps to form and fill up with serous fluid which will cause blisters.

Treatment and prevention of blisters on skin

Since blisters are usually caused by external stresses, avoiding injuries and maintaining a healthy lifestyle can help prevent blisters. Wearing gloves and protective equipment can also help you avoid getting friction blisters.

Treating blisters aren’t usually necessary, but can be safely done if the blister is in an inconvenient location. First, make sure to clean the surrounding area with soap. Use a sterilized needle to make a small incision in the blister. Do not remove the loose skin caused by the blister, and instead, apply an ointment and cover with a dressing to prevent infections.

Key takeaway

Don’t be too worried if you get a blister. This usually means that your body is fighting back or in the process of healing. Just make sure that the blister is not due to an underlying medical condition. When in doubt, consult your physician.

Learn about Other Skin Diseases here.