May also be called: Boil; Carbuncle; Furuncle

An abscess (AB-sess) is a buildup of pus that forms as the body's fights an infection.

What Causes Abscesses?

An abscess can form when bacteria, fungi, or other germs enter a wound (like a cut) and cause an infection. When this happens, the immune system sends white blood cells to fight the infection. The white blood cells can build up in the wound and make pus. When pus builds up, sometimes it can't drain out. This can make the area hurt.

Abscesses usually are red, swollen, and warm to the touch, and they might leak fluid. They can develop on top of or under the skin, in a tooth, or deep inside the body.

How Are Abscesses Treated?

Some abscesses heal with simple treatment at home, like gently placing a warm compress on the area for 20 minutes, three times a day. This helps the infection come to the surface of the skin and drain out the opening. A skin abscess will usually drain and heal with no long-term problems.

For other abscesses, doctors might prescribe an antibiotic. Sometimes they do minor surgery to help drain an abscess. More serious cases might require treatment in a hospital. 

What Else Should I Know?

To help prevent a skin abscess, keep wounds clean, dry, and covered with a bandage.

To help avoid a tooth abscess, kids should avoid sweet and sticky foods, and brush their teeth twice a day and floss.

All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts.