Q: What causes blisters and how are they different from blood blisters?
A: Blisters result from irritation or damage to the skin from an external source. The most common reasons for blisters are:
- Friction: brief and intense rubbing confined to a small area of skin.
- Burns: contact with hot surfaces, exposure to flames, steam, or severe sunburns.
- Irritants, Allergens, or Drugs: contact with certain chemicals, cosmetics, drugs, medications, or plant allergens.
- Infections or Viruses: chickenpox, cold sores, shingles and other infectious illnesses.
Blood blisters differ from regular blisters in that blood blisters result from trauma to the subdermal tissues and/or blood vessels. The trauma leads to bleeding and blood pooling underneath the skin.
The most common cause of blood blisters is pinching of the skin tissue (e.g. pinching your fingers with a pliers.)