Mastitis

(Breast Infection)

Reviewed/Revised Dec 2024
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Mastitis is painful inflammation of the breast, usually with an infection.

If you breastfeed, you may get a breast infection, also called "mastitis." Breast infections usually happen within 6 weeks of giving birth.

  • You have a swollen, red area on your breast

  • The infected area is painful, warm, and tender

  • You may need to take antibiotics

  • It won't hurt your baby to keep breastfeeding even when you have an infection

What causes mastitis?

Breast infections happen when bacteria get into your milk ducts and infect your breasts. This is more likely to happen if the skin of your nipples is cracked. Cracked skin can happen if your baby isn't held in the right position to feed.

What are the symptoms of mastitis?

Part of your breast is:

  • Painful

  • Red

  • Warm

  • Tender to touch

The infection may form a collection of pus called an abscess. An abscess causes a very painful lump.

Rarely, pus drains from your nipple.

How do doctors treat mastitis?

Doctors will:

  • Prescribe antibiotics

  • Tell you to drink plenty of fluids

You can keep breastfeeding your baby during treatment.

If you have an abscess, your doctor may numb the area and make a small cut to drain the pus.

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