Patient education: Boil (The Basics)

What is a boil? — A boil is an infection under the skin that causes a painful, pus-filled lump. A boil happens when bacteria infect a hair follicle. A hair follicle is a sac under the skin where a hair starts to grow (figure 1).

Boils usually happen on the back of the neck, face, armpits, and buttocks. But they can happen wherever hair grows on the body.

The medical term for a boil is "furuncle." Sometimes, a few boils in the same area join together to form a big collection of pus. The medical term for a collection of boils is "carbuncle."

What are the symptoms of a boil? — A boil is a painful, red lump under the skin. It is usually white or yellow in the center.

Boils can start small and grow big quickly. They usually get more painful as they get bigger.

Should I try to treat my boil on my own? — Yes. For your boil to heal, it needs to open so that the pus inside can drain out. Sometimes, boils open and drain on their own. But most boils need help to open and drain. After your boil drains, the pain should get much better.

To help your boil open and drain, put warm pressure on it. You can wet a clean washcloth with warm water and put it on your boil. When the washcloth cools, reheat it with warm water and put it back on the boil. Repeat these steps for 10 to 15 minutes every few hours. Wash your hands after you touch your boil.

Once your boil opens and drains, it should heal on its own. But it can take a few weeks for a boil to open, drain, and heal completely.

Do not squeeze or pop your boil. This can spread the infection.

Should I see a doctor or nurse? — See a doctor or nurse if your boil doesn't get better after you try treating it at home. You should also see the doctor or nurse if:

●Your boil is very painful or gets worse.

●Your boil gets better, but then comes back.

●Your boil is on your face or spine.

●You get a fever.

Will I need tests? — Probably not. To make sure that you have a boil and not another skin condition, your doctor or nurse will ask about your symptoms and do an exam.

They might also take a small sample of pus from inside the boil. Then, they will do lab tests on the sample to find out what kind of bacteria is causing the boil.

What other treatment might I have? — If your boil is very big, your doctor might do a procedure to cut it open so it can drain. If you have a collection of boils, they will cut open the collection of boils to drain.

Depending on your boil and other factors, you might need to take antibiotic medicines.