What are boils?
A boil is a red, swollen, painful bump under the skin. It often looks like an overgrown pimple. Boils are often caused by infected hair follicles. Bacteria from the infection form an abscess, or pocket of pus. A boil can become large and cause severe pain.
Boils most often happen where there is hair and rubbing. The face, neck, armpits, breasts, groin, and buttocks are common sites.
How do you treat a boil?
You can sometimes care for a boil at home.
- Do not squeeze, scratch, drain, or open the boil. Squeezing can push the infection deeper into the skin.
- Gently wash the area with soap and water twice a day. Dry it well.
- Put warm, wet cloths on the boil for 20 to 30 minutes, 3 or 4 times a day. Do this as soon as you notice a boil. The heat and moisture can help the boil to open and drain, but it may take 5 to 7 days. A warm compress or waterproof heating pad placed over a damp towel may also help.
- Keep using heat for 3 days after the boil opens. Put a bandage on it so the drainage does not spread. Change the bandage every day.
- If the boil is draining on its own, let it drain. Keep cleaning it twice a day with soap and water.
- To help keep the infection from spreading, do not share towels and washcloths with other people.
Your doctor may want to cut a small opening in the boil so that the pus can drain out. This is called lancing the boil. He or she will numb the area first. Sometimes gauze is placed in the cut so that it stays open and keeps draining.
Your doctor may also prescribe antibiotics to stop the infection. Take your antibiotics as directed. Do not stop taking them just because you feel better or the boil looks better. You need to take the full course of antibiotics.
When should you call a doctor?
Call your doctor if:
- The boil is on your face, near your spine, or near your anus.
- A boil is getting larger.
- You have any other lumps near the boil, especially if they hurt.
- You are in a lot of pain.
- You have a fever.
- The area around the boil is red or has red streaks leading from it.
- You have diabetes and you get a boil.
- The boil is as large as a ping-pong ball.
- The boil has not improved after 5 to 7 days of home treatment.
- You get many boils over several months.
How can you prevent boils?
If you often get boils in the same spot, gently wash the area well with soapy water every day. Always dry the area well. Do not wear tight clothing over the area.
If you have many boils, your doctor may prescribe a cream or ointment that you put inside your nose. This is because the bacteria that usually cause boils sometimes live inside the nose and then spread to other areas, including your skin. Your doctor may also advise you to take antibiotics for a longer time than normal. These medicines may help keep boils from coming back.
Other Works Consulted
- Craft N (2012). Superficial cutaneous infections and pyodermas. In LA Goldman et al., eds., Fitzpatrick's Dermatology in General Medicine, 8th ed., vol. 2, pp. 2128–2147. New York: McGraw-Hill.
- Morelli JG (2007). Cutaneous bacterial infections. In RM Kliegman et al., eds., Nelson Textbook of Pediatrics, 18th ed., pp. 2741–2745. Philadelphia: Saunders Elsevier.
- Pasternack MS, Morton NS (2015). Cellulitis, necrotizing fasciitis, and subcutaneous tissue infections. In JE Bennett et al., eds., Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases, 8th ed., vol. 1, pp. 1194–1214. Philadelphia: Saunders.
Current as of: July 2, 2020
Author: Healthwise Staff
William H. Blahd Jr. MD, FACEP - Emergency Medicine
Adam Husney MD - Family Medicine
E. Gregory Thompson MD - Internal Medicine
Martin J. Gabica MD - Family Medicine
H. Michael O'Connor MD - Emergency Medicine