Common Causes of Blood Blisters
Most blood blisters are the results of sudden pinching or repeated friction, such as:
Slamming a finger in a door
Wearing tight or poorly fitting shoes
Using tools or sports equipment without protection
Repetitive motions that create pressure on the skin
Blood blisters in the mouth can result from:
Accidental biting
Dental procedures
Sharp or poorly fitting dental appliances
In some cases, blood blisters may appear more easily in people with:
Thin or fragile skin
Circulation issues
Diabetes
Certain blood or clotting disorders
