Breast infection


A breast infection is an infection in the tissue of the breast.


Breast infections are usually caused by common bacteria (Staphylococcus aureus) found on normal skin. The bacteria enter through a break or crack in the skin, usually on the nipple.

The infection takes place in the fatty tissue of the breast and causes swelling. This swelling pushes on the milk ducts. The result is pain and lumps in the infected breast.

Breast infections usually occur in women who are breastfeeding. Breast infections that are not related to breastfeeding might be a rare form of breast cancer.


Symptoms of a breast infection are:

Exams and Tests

An exam is needed to make the diagnosis and rule out complications such as an swollen, pus-filled lump (abscess). Sometimes an ultrasound is needed to check for an abscess.

For infections that keep returning, milk from the nipple may be cultured. In women who are not breastfeeding, tests may include:


Self-care may include applying moist heat to the infected breast tissue for 15 to 20 minutes four times a day. You may also need to take pain relievers.

Antibiotic medicines are usually very effective in treating a breast infection. If you take antibiotics, you must continue to breastfeed or pump to relieve breast swelling from milk production.

Outlook (Prognosis)

The condition usually clears quickly with antibiotic therapy.

Possible Complications

In severe infections, an abscess may develop. Abscesses need to be drained, either as an office procedure or with surgery. Women with abscesses may be told to temporarily stop breastfeeding.

When to Contact a Medical Professional

Call your health care provider if:


The following may help reduce the risk of breast infections:

Review Date: 11/16/2014
Reviewed By: Cynthia D. White, MD, Fellow American College of Obstetricians and Gynecologists, Group Health Cooperative, Bellevue, WA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.

This information should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. © 1997- 2007 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.