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Breast Infection


Julie S. Moldenhauer

, MD, Children's Hospital of Philadelphia

Last full review/revision May 2020| Content last modified May 2020

A breast infection (mastitis) can occur after delivery (postpartum infection), usually during the first 6 weeks and almost always in women who are breastfeeding. If the baby is not positioned correctly during breastfeeding, cracking (and soreness) can develop. If the skin of or around the nipples becomes cracked, bacteria from the skin can enter the milk ducts and cause an infection.

An infected breast usually appears red and swollen and feels warm and tender. Only part of the breast may be red and sore. Women may have a fever.

Rarely, breast infections result in a pocket of pus (abscess). The area around the abscess swells, and pus may drain from the nipple.

Doctors base the diagnosis on results of a physical examination.

Did You Know...

  • If a breast infection develops after delivery, women should usually continue to breastfeed.

Treatment of Breast Infection

  • Antibiotics

Breast infections are treated with antibiotics, such as dicloxacillin, cephalexin, clindamycin or sometimes erythromycin.

Women are encouraged to drink plenty of fluids.

Women who have a breast infection and are breastfeeding should continue to breastfeed because emptying the breast helps with treatment and decreases the risk of a breast abscess.

Breast abscesses are treated with antibiotics and are usually drained surgically. This procedure can be done using a local anesthetic but may require sedatives given intravenously or a general anesthetic.

Drugs Mentioned In This Article

Generic Name Select Brand Names
dicloxacillin No US brand name
erythromycin ERY-TAB, ERYTHROCIN
clindamycin CLEOCIN
cephalexin KEFLEX

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