All topics

Mastitis in Breastfeeding Women

Published on November 5, 2025 at 3:00 / Updated on November 19, 2025 at 8:01

Mastitis is an inflammation of breast tissue happening mostly to breastfeeding women, and particularly in the first weeks.

Causes and triggers

Mastitis happens when one or more milk ducts become swollen. This swelling can narrow the milk ducts to the point that the milk can't reach the nipple. It can be further complicated by a bacterial infection, but not always.

The following factors can promote mastitis, but are not necessary for it to develop:

  • Damaged nipples
  • Insufficient milk removal (e.g., limited or skipped feedings, poor latch)
  • Overproduction of milk
  • Abrupt weaning
  • Pressure on the breast (e.g., tight bra)
  • Tiredness and stress in the mother

Symptoms

The most common signs and symptoms of mastitis are as follows:

  • Hard, warm, swollen and localized lump in the breast
  • Intense fatigue
  • Fever
  • Chills
  • Muscle pain

A swollen and painful lymph node under the armpit may sometimes accompany mastitis.

Treatment

If mastitis is not treated quickly, it can cause a painful lump filled with pus (called an abscess). Continuing breastfeeding or expressing milk regularly helps prevent engorgement and infection. There is no risk for the baby to nurse and drink milk from a breast affected by mastitis. Gently massaging the affected area while pumping milk may promote better expression. However, avoid massaging the breast too deeply, as this could worsen the inflammation. Lactation consultants can provide helpful advice.

Resting and staying well hydrated are, of course, recommended. Applying cold packs after a feed may help reduce pain and inflammation. Analgesics such as acetaminophen (Tylenol) and ibuprofen (Advil) are often recommended to help relieve pain and fever. If there is an infection, an antibiotic could be prescribed. If there are sores on the nipples, your health care professional can suggest a cream that is compatible with breastfeeding.

Here are some recommendations to help prevent mastitis and its complications:

  • Breastfeed when the baby is hungry
  • Make sure the baby has a proper latch
  • Vary breastfeeding positions
  • Avoid long intervals between feeds
  • Avoid abrupt weaning
  • Hydrate properly
  • Get plenty of rest

If mastitis symptoms appear, consult your health care professional as soon as possible.

For more information:

Related services

2
The drugs and pharmaceutical services featured on the familiprix.com website are offered by pharmacists who own the affiliated pharmacies at Familiprix. The information contained on the familiprix.com site is for informational purposes only and does not in any way replace the advice and advice of your pharmacist or any other health professional. Always consult a health professional before taking or discontinuing medication or making any other decision. Familiprix inc. and the proprietary pharmacists affiliated with Familiprix do not engage in any way by making this information available on this website.