Mastitis

Important information:

Mastitis is painful inflammation of the breast/chest that may or may not lead to infection. It is a common lactation problem affecting 1/3 of breast/chestfeeding/pumping parents. Symptoms usually last 2-5 days. Mastitis is preventable.

If you have mastitis, you may have the following symptoms:

• Sudden, intense pain in one breast

• Swelling

• Redness

• Tenderness

• Heat in one breast

• Fever

• Flu-like symptoms

• Nausea

• Aches

• Chills

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There are two different kinds of mastitis:

• Non-infective mastitis: not related to an infection

• Infective mastitis: infection or bacteria based. May need to be treated with antibiotics.

Mastitis usually occurs within the first 6 weeks of breast/chestfeeding but can occur anytime. Typically, due to poor emptying of the breast/chest such as when:

• You go a long time between breast/chestfeedings and/or pumping sessions.

• Your baby sleeps through the night.

• Your baby is not latched well.

• You have cracks in or around your nipple area which can make it possible for bacteria to enter breasts/chest and spread to milk ducts.

• You have an overproduction of milk.

• You are tired or stressed.

• You wean rapidly.

If you have had mastitis before, you are more likely to get it again. Recurrent mastitis can lead to breast/chest abscess (tender lump within the breast/chest) which may require surgical intervention.

Tips to prevent mastitis:

• Reduce stress and fatigue.

• Get household help.

• Take naps.

• Delay returning to work when possible.

• Pump or breast/chestfeed at least 8-12 times per day.

• Gently massage any red or firm areas of the breast/chest while pumping or breast/chestfeeding.

• Pump or express milk if you miss a feeding.

• Pump or express milk if your breasts/chest are engorged (swollen) or still full after a feeding.

• Avoid underwire or tight-fitting bras that block milk flow.

Instructions if you have mastitis:

Keep pumping and/or breast/chestfeeding!

• Milk removal is very important.

• Gently massaging your breast/chest during feeding or pumping can help with milk removal.

• Your baby will not get sick from your milk.  

Call a provider who specializes in lactation support or your primary health care provider.

• There is not enough evidence to confirm or deny that antibiotics are effective treatment for mastitis.

• If your provider prescribes antibiotics, (this will reduce the chance of recurrence or an abscess) be sure to finish all the medication prescribed.

Take pain medication.

• Acetaminophen (Tylenol®) or ibuprofen (Advil®).

• These medications may help decrease swelling too.

Apply ice packs or hot packs.

• Cold will help swelling and may give pain relief.

• Heat will help drain the breast/chest and may give pain relief.

Drink plenty of fluids. If your urine is pale and clear, you are well-hydrated.

Special note for breast/chestfeeding:

If you are breast/chestfeeding, start feeding with the affected side to allow your baby to empty the milk from the breast/chest. If it is too painful, start on the unaffected breast to allow your milk to let-down in the affected breast. Doing this should reduce your pain. You may also replace breast/chestfeeding with a pumping session if it is too uncomfortable to directly breast/chestfeed. The most important thing is to ensure that you continue to stimulate and empty your breasts/chest so that you maintain your milk production.

Reviewed June 2024 by Meghan Devine BSN, RN, IBCLC