Breast Infection (Mastitis): Symptoms and Treatment

Medically Reviewed by Poonam Sachdev on March 14, 2024
13 min read

Mastitis is an inflammation of the breast. It sometimes involves a breast infection, but not always.

The catchall name for inflammation of the breast tissue is mastitis. If you're breastfeeding, it's called lactational or puerperal mastitis. If you're not, it's called nonlactational mastitis.

Mastitis is most common in parents who're breastfeeding, but anyone can get it, though it's rare in cisgender men.

Can you breastfeed with mastitis?

Yes, you can safely continue to breastfeed. Nursing might even help to clear up an infection. 

But mastitis breastfeeding isn't a good idea if you have a collection of pus called an abscess. You'll need to have the abscess drained before you continue to breastfeed.

Mastitis vs. engorgement

Engorgement is what happens in the 2-4 days after your baby is born and your breasts start to swell, as your milk comes in. Your body sends more fluid and blood to your breasts to help with milk production and this can cause pain. Symptoms usually peak around day 5 and seldom last longer than 2 weeks after your baby's birth. Unlike with mastitis, no antibiotics are needed for treatment. Home remedies usually are enough.

Mastitis vs. clogged duct

A clogged duct is a blockage of milk inside one of your milk ducts (tubes in your breasts). You may feel a small lump in your breast that could hurt. It can happen if you wait too long to empty your breasts of milk or don't empty all the milk at each feeding. The good news is, it usually goes away on its own in 24-48 hours without any special treatment. Breastfeeding with a clogged duct can help it get better faster. Unlike with mastitis, no antibiotics are needed, nor is there a fever.

The breast is made of several glands and ducts that lead to the nipple and the surrounding colored area called the areola. The milk-carrying ducts extend from the nipple into the breast tissue under it like the spokes of a wheel. Under the areola are lactiferous ducts. These fill with milk during lactation after you have a baby. When a girl reaches puberty, changing hormones cause the ducts to grow and increase at deposits in the breast tissue. The glands that produce milk (mammary glands) that are connected to the surface of the breast by the lactiferous ducts may extend to the armpit area.

Mastitis is divided into lactational (breastfeeding) and nonlactational types.

Lactational mastitis 

This is the most common type and happens during breastfeeding. The milk ducts of the breasts are engorged due to an infection from bacteria breaking through the skin. Staphylococcus aureus is the most common bacteria.

Periductal mastitis

This is a nonlactational mastitis that is benign (not cancer). The ducts under the nipples become inflamed and infected. This mostly affects women of reproductive age.

Granulomatous mastitis

This is a rare nonlactational mastitis, affecting mostly women within 5 years of giving birth. The breasts are inflamed and can mimic the symptoms of breast cancer. However, the condition is benign.

 

Mastitis is a common condition in women who breastfeed. As many as 1 in 10 breastfeeding women in the United States get it. The most common cause is when one or more of your milk ducts becomes clogged and the milk inside backs up. This usually happens when you produce more milk than your baby can take in at a time. When milk backs up, it clogs the milk duct and irritates the tissues around it. The clogged milk duct may make your breast swell up or become engorged. 

A blockage can also happen if your baby isn't sucking or attaching properly, or if they favor one breast over the other. Another reason is if you don't feed or pump regularly. Doctors call this inflammatory mastitis. A rare type of cancer called inflammatory carcinoma can also cause mastitis.

Mastitis can also occur when bacteria from your baby's mouth or from your skin get into a milk duct through a crack in the nipple. The bacteria can breed in milk that's left in the breast, causing swelling. This is called bacterial mastitis. 

You're more likely to get mastitis in the first 3 months of breastfeeding. 

In the case of periductal mastitis, bacteria can get into your milk ducts through a cut or crack in the nipple and cause an infection. Periductal mastitis is more common in women who smoke, have diabetes, are obese, or have nipple piercings.

The cause of granulomatous mastitis isn't clear. It has been associated with autoimmune diseases, a reaction to childbirth, or with the use of oral contraceptives. However, there are cases of people developing this condition who don't meet these criteria.

 

You're more likely to get mastitis if you:

  • Had mastitis before
  • Have sore or cracked nipples
  • Use the wrong breastfeeding technique
  • Have too much breast milk
  • Put pressure on your breasts (wearing a tight bra, carrying a heavy crossbody bag, wearing a snug seat belt)
  • Are very tired or stressed
  • Smoke
  • Don't pump or nurse on a regular schedule 
  • Don't get proper nutrition
  • Have a chronic health condition such as diabetes 
  • Have an impaired immune system, including from an HIV-positive status

When you have too much milk, you may feel that you need to nurse or pump more often to get it all out of your breasts. But this will cause your body to make even more milk and may make the problem worse. Staying on a regular schedule will help your body adjust to making the right amount of milk for your baby.

Early signs of mastitis

The early signs can come on very suddenly. You may feel like you're getting the flu before you feel any pain or swelling in your breast. If you feel pain or see redness, call your doctor as soon as possible.

These are some common mastitis symptoms:

  • Breast pain, warmth, and swelling 
  • Redness in a triangle- or wedge-shaped pattern
  • A lump or thickening in the breast
  • A fever of 101 F or higher
  • Flu-like symptoms such as body aches or chills
  • Tiredness
  • Swollen or tender lymph nodes in the armpit on the same side as the affected breast
  • Itching

Abscess: A breast abscess can be a complication of mastitis. Noncancerous masses such as abscesses are more often tender and frequently feel mobile beneath the skin. The edge of the mass is usually regular and well-defined. This may be a more serious infection if you have:

  • A tender lump in the breast that does not get smaller after breastfeeding a newborn (If the abscess is deep in the breast, you may not be able to feel it.)
  • Pus draining from the nipple
  • A persistent fever and no improvement of symptoms within 48-72 hours of treatment

A breast infection caused by inflammatory breast cancer also causes redness and swelling. The skin of the breast can look pink, reddish-purple, or like a bruise. You might see dimpling of the skin that looks like the texture of an orange peel. Let your health care provider know about these symptoms right away.

How long does mastitis last?

Once you start treatment, you should see an improvement in 24 to 72 hours. You should be completely better in 10-14 days.

Call your health care provider as soon as you feel any suspicious lump, whether you are breastfeeding or not. Call for an appointment if:

  • You have an abnormal nipple discharge.
  • Significant breast pain is making it difficult for you to function each day.
  • You have other symptoms such as redness, swelling, pain that interferes with breastfeeding, or a mass or tender lump in the breast that does not disappear after breastfeeding.

When to seek emergency treatment for mastitis

You may need to be evaluated in a hospital's emergency department if the breast pain is linked to other signs of an infection (such as a fever, swelling, or redness to the breast) and if your health care provider cannot see you right away. The below symptoms require emergency treatment:

  • A persistent high fever greater than 101.5 F
  • Nausea or vomiting that is preventing you from taking the antibiotics as prescribed
  • Pus draining from the breast
  • Red streaks extending toward your arm or chest
  • Dizziness, fainting, or confusion

The diagnosis of mastitis and a breast abscess can usually be made based on a physical exam.

If it's unclear whether a mass is due to a fluid-filled abscess or to a solid mass such as a tumor, you may get a test such as an ultrasound. An ultrasound may also tell whether you have simple mastitis, or an abscess deep in the breast. This noninvasive test allows your doctor to see the abscess by placing an ultrasound probe over your breast to get an image. If an abscess is confirmed, aspiration or surgical drainage, and IV antibiotics, are often required.

A nurse or lab tech may take a sample (culture) either of breast milk or of material from an abscess through a syringe, to find out the type of organism causing the infection. This information can help your doctor decide what kind of antibiotic to use.

Non-breastfeeding women with mastitis, or those who do not respond to treatment, may have a mammogram or breast biopsy. This is a precaution because a rare type of breast cancer can produce symptoms of mastitis.

Mastitis treatment depends on whether you have an abscess. Your doctor will most likely prescribe antibiotics for a simple infection without an abscess. If you have an abscess, you may need surgery to drain it.

Antibiotics for mastitis

Antibiotics are safe to use while you breastfeed and won't harm your baby. You should start to feel better 2 to 3 days after you start antibiotics. 

If the infection gets worse or you have a deep abscess that needs surgery, you may need to get IV antibiotics in a hospital.

For simple mastitis without an abscess, your doctor will prescribe oral antibiotics. The most common ones are cephalexin (Keflex) and dicloxacillin (Dycill), but others are available. The antibiotic you'll get will depend on your specific situation, your doctor's preference, and any drug allergies you may have. If you are prescribed antibiotics, it's important to finish the prescription even if you feel better in a few days. 

Chronic (ongoing) mastitis in non-breastfeeding women can be complicated. Sometimes, antibiotics don't work well for this type of infection and the mastitis comes back. 

Surgery for mastitis

Doctors treat abscesses with a minor procedure. This may be done in the doctor's office or in a hospital. First, you'll get a local anesthetic to numb the area. The doctor can drain an abscess that's near the surface of your skin with a needle and syringe or through a small cut in the skin. 

If the abscess is deep in your breast, you may need surgery in an operating room to drain it. The procedure is usually done while you are asleep under general anesthesia.

What happens if you don't treat a breast infection? 

Can mastitis go away on its own? Sometimes, breast infections do clear up without treatment. But the risk of not treating a breast infection is that pus could collect in your breast and form an abscess. An abscess will usually need surgery to drain.

After you see a doctor, try the following to help your breast infection heal.

Pain relief for mastitis

  • Take acetaminophen or ibuprofen for pain. These drugs are safe while breastfeeding and will not harm your baby. Your doctor may order a prescription-strength pain reliever if your pain is severe and not relieved with over-the-counter medication.
  • Apply ice. Place an ice pack or a bag of frozen vegetables on the swollen breast to bring down swelling. Avoid using ice packs just before breastfeeding because it can slow down milk flow. 

Other mastitis home remedies

  • Try lymphatic drainage. Press on your breast as if you were petting a cat, moving your hand from your breast toward the lymph nodes in your collarbone and armpit. This motion gently pushes fluid into your lymph drainage system. 
  • Use reverse pressure softening. Place two fingertips around the base of your nipple. Then pull your fingers away from your nipples while you apply pressure to your breast. This moves fluid away from your areola and reduces pressure.
  • Drink extra fluids. Try to take in about 16 cups a day from foods and drinks like water. Dehydration can decrease your milk supply and make you feel worse.

Cabbage leaves for mastitis

Surprisingly, cabbage leaves can ease mastitis pain, though they can't clear the infection. Cabbages, like other cruciferous vegetables, have anti-inflammatory properties. To use:

  1. Crush green cabbage with a rolling pin to flatten the leaves. Do this only if you need to get them to fit your breasts' shape.
  2. Wrap the leaves around your breasts and leave then on for about 20 minutes twice a day.
  3. Stop using when your breasts start to be less engorged. You may not need more than 2 or 3 treatments.

What kind of bra to wear with mastitis

Look for one that supports your breasts but isn't too tight. A too-tight bra can caused clogged milk ducts and inflame breasts. For this reason, some experts suggest avoiding underwire bras as they may put pressure on a full breast and inflame it.

You can breastfeed with mastitis. In fact, it is encouraged, as it can help clear the infection; also, breast milk helps babies fight infections. Any antibiotics you take shouldn't harm your baby.

Breastfeeding tips for mastitis

  • Don't nurse more often than usual to relieve the pressure in your breast. If you feed your baby or pump too much, it could stimulate more milk production and make mastitis worse.
  • Breastfeed on the side with mastitis first to relieve some of the pressure.
  • Make sure your baby drains the affected breast completely. If the breast isn't fully draining, apply warm, moist heat before you nurse or use a pump to drain it.
  • Massage the breast while you breastfeed. Rub down from the affected area toward the nipple.

If you have a breast infection, you may need a recheck in 24-48 hours.

  • Take all antibiotics as prescribed.
  • Take your temperature 3 times a day for the first 48 hours after treatment begins. Watch for a fever.
  • Call your doctor if you have a high fever, vomiting, or increasing redness, swelling, or pain in the breast.
  • Follow up with your doctor in 1 to 2 weeks to make sure the infection has gone away. If the infection spreads or an abscess develops, you may need IV antibiotics or surgery.

Mastitis does not cause cancer, but cancer can mimic mastitis in appearance. If a breast infection is slow to go away, your doctor may recommend a mammogram or other tests to rule out cancer.

Sometimes mastitis is hard to prevent. Some people are more likely to get it than others, especially those who breastfeed for the first time. 

If you're wondering how to avoid mastitis, try these habits:

  • Drink plenty of fluids to avoid dehydration.
  • Eat a well-balanced diet. Get more lecithin from foods like soybeans, peanuts, and egg yolks. Lecithin makes breast milk less sticky to prevent it from plugging up the breast ducts.
  • Keep your clothes light and loose. Tight shirts put pressure on your breasts.

Breastfeeding habits to prevent mastitis

  • Practice good hygiene when you breastfeed. Wash your hands and clean your nipples each time.
  • Breastfeed equally from both breasts.
  • Empty your breasts completely to prevent engorgement and blocked ducts.
  • Use good breastfeeding techniques so you don't get sore, cracked nipples. A lactation consultant can help if you need support.
  • Let sore or cracked nipples air-dry.
  • Prevent moisture buildup in breast pads or bras.

When treated promptly, most breast infections go away quickly and without serious complications. 

Unless your doctor says otherwise, continue to breastfeed even when you have mastitis. With proper treatment, symptoms should begin to clear up in 1 to 2 days.

If you have a breast abscess, it may require surgical drainage, IV antibiotics, and a short hospital stay. A small cut is made and usually heals quite well. The outlook for a complete recovery is also good.

If you've been through menopause and have an abscess, it's likely to come back after simple drainage. You'll need to follow up with a surgeon for more treatment. A chronic infection can happen if an abscess is not completely drained. This can cause a change in how your breasts look.

What does an infection in your breast feel like?

A breast infection causes warmth, swelling, and pain in the affected breast. Symptoms can feel like the flu, with a fever, aches, and chills. Other symptoms are a wedge-shaped area of redness and a lump or thickening in the breast.

What happens if you don't treat a breast infection?

If you don't treat a breast infection, pus could collect in your breast and form an abscess. An abscess will usually need surgery to drain.

Can I get rid of mastitis on my own? 

Sometimes it goes away on its own, if you try home remedies like breastfeeding on the affected side every 2 hours or more and massage the affected breast. If you don't feel better in 24 hours after doing these things, call your doctor. You may need antibiotics.