The signs of mastitis while breastfeeding, the newer advice on ice and gentle care instead of heat and deep massage, when antibiotics are needed, and when to call.
Mastitis is inflammation of the breast, sometimes with infection. It usually causes a painful, swollen, warm area in one breast, often with flu-like aches, chills or fever. Most mothers get it in the first months of breastfeeding. Early on, it often settles with rest, ice, an anti-inflammatory pain reliever and feeding your baby as normal. Call your clinician if you have a fever, feel very unwell, or aren’t improving within about a day, because you may need antibiotics.
Mastitis symptoms
Symptoms usually come on quickly and affect one breast:
- A painful, tender area, often wedge-shaped
- Redness, or on darker skin, an area that looks darker or purplish, or no color change at all
- Warmth and swelling, sometimes with a firm lump
- Burning pain, during feeds or all the time
- Flu-like aches, chills and tiredness
- A fever of 101°F (38.3°C) or higher
Many mothers feel the body aches before they notice the breast. If you feel suddenly unwell while breastfeeding, check your breasts.
What is mastitis?
Experts now describe mastitis as a spectrum. It can start with swollen, narrowed milk ducts (often called a clogged duct), progress to inflammation, and sometimes to bacterial infection. Rarely, an infection forms a pocket of pus called an abscess. Most cases stop at inflammation and never need antibiotics.
Common triggers include:
- Oversupply, often from pumping more than your baby needs
- Missed or rushed feeds, or sudden changes in feeding
- Pressure on the breast from a tight bra, bag strap or sleeping position
- Cracked or damaged nipples
- A poor latch or an ill-fitting pump flange
- Stress and exhaustion
Mastitis treatment: what helps
Advice changed in 2022, when the Academy of Breastfeeding Medicine updated its guidance. The focus is now on calming inflammation, not “emptying” the breast:
- Feed your baby normally, on demand from both breasts. Don’t feed or pump extra on the sore side to “drain” it, which can make swelling worse.
- If you pump, pump only what your baby needs.
- Use ice or a cold pack, wrapped in a cloth, for 10 to 20 minutes after feeds.
- Take an anti-inflammatory pain reliever such as ibuprofen, as directed on the label or by your clinician. Acetaminophen can help with pain. Both are generally considered compatible with breastfeeding.
- Wear a supportive, well-fitting bra, not a tight one.
- Use only light, sweeping strokes on the skin, from the nipple toward the armpit, to move fluid. This is very gentle, not kneading.
- Rest, eat and drink to thirst. Ask for help with the baby and the house.
What to avoid
- Deep massage or pushing hard on a lump. It can injure tissue and increase swelling.
- Vibrating devices or electric toothbrushes on the breast
- Long heat sessions. Heat can add to swelling. A brief warm compress before a feed is fine if it feels soothing.
- Salt soaks and other topical home remedies
- Extra pumping to “empty” the breast
- Stopping breastfeeding suddenly, which can make things worse
When you may need antibiotics
Call your clinician the same day if you have a fever, feel very unwell, your symptoms aren’t improving after 12 to 24 hours of self-care, or they’re getting worse. Bacterial mastitis needs prescription antibiotics, and there are options that are safe while breastfeeding. Take the full course, and call back if you aren’t better in 2 to 3 days.
Seek urgent care for a high fever, red streaks spreading from the area, a hard or squishy lump that keeps growing, pus or blood from the nipple, a racing heart, feeling faint, confusion, or feeling very sick. These can mean a spreading infection or an abscess, which may need drainage.
Can I keep breastfeeding with mastitis?
Yes. Breastfeeding is usually safe for your baby during mastitis, including while you take most antibiotics, and keeping milk moving helps you recover. If feeding from the sore side is too painful, start on the other side, and ask a lactation consultant for help.
How to lower your risk
- Feed on your baby’s cues rather than by the clock
- Avoid pumping much more milk than your baby needs
- Get latch and flange fit checked if your nipples are sore or damaged
- Wear supportive bras without tight underwires or straps
- Make changes to feeding gradually, especially when weaning
If you’re pumping to build supply, use a limited plan such as power pumping for a few days rather than open-ended extra pumping, and stop if your breasts become sore. See also How to Increase Milk Supply.
Breast redness when you’re not breastfeeding
Mastitis can happen outside breastfeeding, but it’s less common. Any breast redness, swelling or a lump that doesn’t clear up, or doesn’t improve with antibiotics, needs a doctor’s exam. A rare breast cancer can look like mastitis.
A note on the Breastfeeding Support pouch
The Breastfeeding Support herbal pouch isn’t a treatment for mastitis or any breast problem. It’s worn away from the breasts, over the navel or at the lower back after a cesarean birth. If you develop mastitis symptoms, focus on the care above and contact your clinician; don’t start a new product while you’re unwell, and ask your clinician before resuming one.
Quick answers
How long does mastitis last?
Inflammatory mastitis often improves within a day or two of self-care. Bacterial mastitis usually improves within 2 to 3 days of starting antibiotics.
Can mastitis go away on its own?
Mild mastitis often does with rest, ice and anti-inflammatories. Call your clinician if you have a fever or don’t improve within a day.
Should I use heat or ice for mastitis?
Ice. Current guidance favors cold to reduce swelling; a brief warm compress before feeding is fine if it helps.
Is it mastitis or a clogged duct?
A clogged duct is a tender spot without fever or aches. Mastitis usually adds redness, warmth and flu-like symptoms. Both sit on the same spectrum and start with the same gentle care.
Reviewed October 2026. Author: Qingcai Wang, MD, PhD, developer of the Five Essences external herbal-pouch formulations, with a commercial interest in their sale. General education only; contact your clinician about breast pain, fever or infection.
Sources: Academy of Breastfeeding Medicine, Clinical Protocol #36: The Mastitis Spectrum, revised 2022; NHS, Mastitis.