In short
Blisters are fluid-filled sacs on the outer layer of your skin.
Worth knowing2
They form because of rubbing, heat, or diseases of the skin.
MedlinePlusBlisters often happen when there is friction - rubbing or pressure - on one spot.
MedlinePlus
What helps3
Blisters will usually heal on their own.
MedlinePlusThe skin over the blister helps keep out infections.
MedlinePlusYou can put a bandage on the blister to keep it clean.
MedlinePlus
What to avoid1
Normally you don't want to drain a blister, because of the risk of infection.
MedlinePlus
See a provider if1
See a health care provider if: the blister looks infected - if it is draining pus, or the area around the blister is red, swollen, warm, or very painful; you have a fever; you have several blisters, especially if you cannot figure out what is causing them; you have health problems such as circulation problems or diabetes.
MedlinePlus
Sources
These pages describe what the sources say. They cannot say what is going on with your skin.
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