An abscess is the body's way of trying to heal from an infection. Abscesses form after bacteria, fungi, or other germs enter the body — usually through an open wound like a cut — and cause an infection.
An abscess might appear on the skin, under the skin, in a tooth, or even deep inside the body. On top of the skin, an abscess may look like an unhealed wound or a pimple. Underneath the skin, it may create a swollen bump. A skin abscess might hurt and feel warm when you touch it.
It's easier to tell if you have a skin abscess because you can see and touch it. But when someone gets an abscess in another part of the body, there will still be clues that something is wrong. With a tooth abscess, for example, people will feel pain even though they can't see the abscess.
What Causes an Abscess?
Abscesses can form wherever the body is fighting off an infection. For example, a skin abscess can appear when germs get into the body through an opening in the skin (like a cut, insect sting, or burn).
Most germs don't belong in a healthy body and the immune system knows it: It's the immune system's job to be on the lookout for infection. After figuring out that something is wrong, it sends in the troops (otherwise known as white blood cells) to destroy whatever's causing the infection. Some of these white blood cells will end up in pus, which also includes stuff like dead skin and dead germs.
The body considers pus garbage and will try to get rid of it. But when pus collects in an abscess, it may not be able to drain out. As pus builds up, it can press against the skin and surrounding tissue, causing pain.
Some abscesses are caused by an irritant like an injected medication that was not completely absorbed. Since they're not caused by infection, these kinds of abscesses are called "sterile" abscesses. Sterile abscesses aren't as common as infected abscesses, but they can happen on occasion.
How Are Abscesses Treated?
Most abscesses can be managed at home. If you think you have a skin abscess, avoid touching, pushing, popping, or squeezing it. Doing that can spread the infection or push it deeper inside the body, making things worse.
Try using a warm compress to see if that opens up the abscess so it can drain. You can make a compress by wetting a washcloth with warm — not hot — water and placing it over the abscess for several minutes. Do this a few times a day, and wash your hands well before and after applying the washcloth.
If the abscess opens on its own and drains, and the infection seems to clear up in a couple of days, your body should heal on its own. If it doesn't, it's time to call your doctor's office.
If you have tooth pain and you suspect there may be an infection, call your dentist.
When Should I Call a Doctor?
Sometimes, an abscess needs a doctor's care. If you notice any of these problems, call your doctor:
A skin abscess becomes more painful, swollen, and red.
Red streaks develop around the infected area of skin.
You have pain or discomfort inside your body.
You have a fever or chills.
If a doctor thinks you have an abscess, he or she will decide if it needs to be drained or if it can be treated another way, like with antibiotics.
If an abscess needs to be drained, the doctor will decide if it's best to pull out the pus using a needle (called aspiration) or to make a small cut in the abscess with a scalpel so the pus can drain out.
For a skin abscess, the doctor will probably use numbing medications before draining an abscess so it's not too painful. After the doctor drains the abscess, he or she may pack it with gauze. The gauze will soak up drainage and help the abscess heal.
An abscess that is deep inside the body might require surgery. This may mean staying in the hospital for a while so doctors and nurses can be sure the person heals properly.
How Can I Feel Better?
Your doctor will give you instructions about how to take care of an abscess so it heals properly. Your doctor also might tell you to avoid specific activities until the abscess heals. You may need to take antibiotics, and you (or your lucky mom or dad!) might have to change a bandage regularly.
If your doctor prescribes antibiotics, take all the medicine until it's gone — even if you start feeling better.
If you have a skin abscess, take steps so you don't spread the infection to anyone else. Don't share anything that's touched your abscess (like washcloths, towels, athletic equipment, or razors).
Even after a visit to the doctor, you'll still need to keep an eye on the abscess. Let your doctor know right away if it gets worse or if you develop a fever or chills.
If you have a skin abscess, your doctor might want to do tests to find out if you have something called MRSA, a kind of bacteria that can cause serious skin infections. MRSA infections need special treatment because they are resistant to many kinds of antibiotics.
Can Abscesses Be Prevented?
Good hygiene is the best way to avoid infection. Keep cuts and wounds clean, dry, and covered to protect them from germs. Also, don't share clothing, towels, razors, or bed linens with anyone else. When these items get dirty, wash them separately in very hot water.
Wash your hands well and often using plain soap and water for at least 20 seconds each time. It's OK to use alcohol-based instant hand sanitizers or wipes (the kind that you can pick up at a drugstore) if you're not near any soap and water.