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Mastitis while breastfeeding

Mastitis is an inflammation of the breast. It is sometimes accompanied by a bacterial infection. The pain, heat and swelling can be very intense.

You may notice a:

  • hard and painful lump
  • hot and red wedge-shaped area of engorgement (when your breasts get too full of milk)
  • raised temperature

Causes of mastitis

Causes of mastitis include:

Types of mastitis

These can range from unrelieved engorgement to:

  • non-infective mastitis
  • infective mastitis

Non-infective mastitis symptoms

Non-infective mastitis can happen when a milk duct or lobe is not draining well and becomes inflamed.

With non-infective mastitis, you will feel generally well and:

  • your breast will feel hot and sore (mainly in one area of the breast)
  • the symptoms are gradual, not sudden
  • only 1 breast will be affected

You may also experience a rise of temperature. But this should be no higher than 38.3 degrees Celsius and last no longer than 24 hours.

Infective mastitis symptoms

With infective mastitis, your breast may feel tender, hot and swollen.

Other symptoms may include:

  • a fever or high temperature (38.3 degrees Celsius or higher)
  • chills
  • flu-like symptoms (aches and pains all over the body)
  • a tender, hot, swollen area of the breast
  • generally feeling unwell

Urgent advice: Contact your GP, lactation consultant or maternity hospital immediately if:

  • you have flu-like symptoms with signs of a breast infection

Breastfeeding with mastitis

Breastfeeding is the best way to relieve a blockage. Gentle massage and breast compression will help to get breast milk flowing. Using a warm compress on your breast for 2 to 3 minutes before a feed may also help.

If you can breastfeed your baby, try starting on the affected breast if possible. Your breast milk may not release if you are in pain. If this happens, try breastfeeding on the unaffected breast. Move back to the affected breast as soon as the breast milk starts releasing.

Breastfeeding may be too painful. If so, use gentle hand-expression or a breast pump to remove milk from the affected breast.

Expressing by pump or hand

It may help to fully remove the milk from your affected breast by expressing. You can do this by hand or by pump after the feed from the other, unaffected breast.

If you're using a breast pump, remember to keep the pump and attachments clean. Follow hospital or home-use guidelines. Begin pumping on a low setting, then turn up the setting as far as you can take it without it being painful.

How to treat mastitis

Regular breastfeeding is the best way to relieve mastitis. It can treat both non-infective and infective mastitis.

Before each feed carefully wash your hands and remove any source of pressure from your breast. For example, clothing or a bra that is too tight.

When you are ready to feed:

  1. Put a warm face cloth on your breast.
  2. Begin feeding on the sore breast if possible. Try changing feeding positions if one does not work.
  3. While breastfeeding, gently massage your breast behind the sore area. This may help the milk to flow.

Drink plenty of fluids and look for signs of a developing breast infection. For example, a temperature, chills and aches throughout the body.

Doing breast massage in the shower

If breastfeeding does not work, you can try breast massage in the shower:

  1. With your breast well-soaped, apply steady but gentle pressure behind the plugged area.
  2. Press toward the nipple as you massage.
  3. Gently massage the area around your armpits and the front of your neck. This improves drainage in your lymph nodes and can help to reduce swelling.


If a breast lump does not get smaller within a week, ask your GP to examine it.

Other treatment for infective mastitis


Ask your midwife or PHN if it's safe to take a non-steroidal anti-inflammatory medicine. For example, ibuprofen. This may relieve symptoms such as a temperature and a painful and aching breast.

Always take the full course of any medicines you are prescribed.

Breast massage

Put an edible oil or non-toxic lubricant on your fingers and gently massage the affected breast. This will help with breast milk removal. The massage should start from the blockage and move towards the nipple.

Apply warmth

Apply warmth to your breast along with gentle massage before breastfeeding. This can help with the release and flow of your breast milk. You can do this with a warm shower or a facecloth dipped in warm water.

When you have finished feeding, put a cold pack on your breast to help with soreness and swelling.

Therapeutic ultrasound (TUS) can also help to release blockages and help milk to flow. This is given by a trained lactation consultant or physiotherapist. The process may often have to be repeated for a few days in a row. Ask your lactation consultant for more information about TUS.


It is important for you to rest and eat and drink well. Ask for help and support from your partner and family.

Milk supply

You may notice that when the mastitis clears up, you produce less milk than before the infection. This is temporary and your milk supply will return. Lots of feeding and contact with your baby will help.

Concern about your milk supply


If your symptoms do not improve, talk to your GP or lactation consultant.

Page last reviewed: 20 August 2022
Next review due: 20 August 2025