A blister is a painful skin condition where fluid fills a space between layers of skin. They form when something — like too-tight shoes — repeatedly rubs against your skin. These fluid-filled bubbles are a pain, but you can treat them easily at home.
Your skin consists of three layers: the epidermis, the dermis and subcutaneous (below the skin) fat. A blister forms under the epidermis as a fluid-filled sac. Typically, it may be filled with clear liquid or blood, depending on the injury that damaged your skin.
Blisters may be painful or itchy. If a blister gets infected, it will fill with milky-white pus. Blisters most often show up on the feet or hands, but they can appear anywhere on the body.
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You can get blisters in several different ways, including some diseases. The most common types of blisters include:
Blisters generally do not need a healthcare provider to look at them. There are no tests or diagnostics for blisters.
If a burn or frostbite caused your blisters, a healthcare provider may need to treat the underlying cause. You may also need to see your provider if a blister shows signs of infection, such as:
Blisters generally heal on their own within a few days. You can do a few things at home to make them more comfortable:
Be sure to change the bandage at least once a day. And resist the temptation to pop or break a blister or peel it off. The skin on the blister protects deeper layers of skin from infection.
You have several options for preventing blisters. Most involve preparation and caution. Preventing blisters depends on the type of blister:
Friction blisters: Friction blisters result from repeated rubbing. To prevent them:
Blood blisters: These blisters usually develop when something pinches part of your skin. They typically happen on the hands. It’s harder to prevent them, but take these steps:
Heat blisters: Heat blisters can result from a burn or when your skin gets too hot as you recover from frostbite. To prevent them:
Most blisters heal naturally on their own in a few days. Be sure to bandage the blister and wear different shoes while it heals. If you have blisters from burns or frostbite, or you think your blisters could be infected, consult your healthcare provider.
You should see a healthcare provider if your blister does not improve after a few days. You should also see a provider if the blister appears infected. If it is infected, your skin will be red and swollen. The blister fills with a white or yellowish fluid rather than a clear fluid or blood.
A note from Cleveland Clinic
Blisters are pretty standard, but it doesn’t make them any less painful. For runners, hikers and anyone on their feet a lot, blisters can be a major pain. If you get a blister, it should get better on its own in a few days. If your blister appears infected, see your healthcare provider.
Last reviewed by a Cleveland Clinic medical professional on 04/30/2021.
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