Boils and Carbuncles: Health Topics: University of Iowa Health Care

Boils and carbuncles

Boils are infected, pus-filled swellings in the skin that are often located in or near hair follicles. They are most often found on the back of the neck and in other moist areas of the body like the armpits and groin, but may be anywhere on the body. Sometimes several boils form close together in a cluster. Clusters of boils are called carbuncles. Carbuncles form in the same areas as boils, and may also form on the scalp, face, and buttocks.

The bacteria that cause boils and carbuncles exist naturally in the body. Rarely, boils and carbuncles may be caused by a weak immune system.

A boil starts out suddenly as a red, painful lump. Usually within 24 hours, the lump fills with pus and takes on a round appearance with a yellow-white tip. There may be swelling around the boil as well as swelling of any lymph nodes near the boil. Lymph nodes are located in the neck, armpit, and groin area.

Boils may take from 10 to 25 days to heal. In most cases, a boil will not heal until it bursts and drains. This can take as long as 2 weeks. A single boil can usually be cared for at home and does not require a trip to a doctor. Since releasing the pus in a boil can lead to more infection, puncturing it at home is not advised.

Self-care for boils:

apply warm, moist compresses for 20 minutes 4 times a day
take showers instead of baths (baths can spread infection)
keep the boil covered with a clean bandage
gently wash the sore twice a day with antibacterial soap
never squeeze or lance a boil, because you may spread the infection
wash hands frequently, especially after touching the infected area and
launder in hot water towels, washcloths, sheets, and clothing that have touched the infected area

When the boil bursts, apply an antibiotic ointment (like Bacitracin or Neosporin) to reduce the chance of infection. Keep the skin around it clean, and wash the hands carefully after touching the area. The bacteria responsible for boils can also cause food poisoning.

Seek medical care when:

a boil develops in a child, elderly person, or a person with diabetes, anemia, or who is in poor health
a boil develops on the face near the eyes or nose
a boil becomes extremely large or painful
a cluster of boils form or
boils become increasingly common

Also, if bacteria from a boil get into the bloodstream, it can poison the blood. Blood poisoning can be very serious. Seek medical care immediately if the following symptoms occur:

red lines spread out from the center of the boil
the boil is extremely tender
ever and chills develop or
lymph nodes begin to swell that are located in other areas of the body from where the original lymph node swelling occurred

Medical treatment by a healthcare provider may include lancing or puncturing the boil to release the pressure and allow for drainage. Antibiotics may be prescribed to stop the infection.

Practicing good hygiene habits minimizes the frequency of recurring boils and prevents the spread of infection. This includes not picking at boils, using clean towels after each bath or shower, and cleaning the skin with an antiseptic soap.

Last Reviewed 2005

Disclaimer: This content is reviewed periodically and is subject to change as new health information becomes available. The information provided is intended to be informative and educational and is not a replacement for professional medical evaluation, advice, diagnosis or treatment by a healthcare professional.