breastfeeding baby

How do you know if you have a blocked milk duct? And what’s the best way to treat it? Find out everything you need to know here.

If you’re breastfeeding and you feel a small, tender lump in your breast, you might have a blocked milk duct. But what is that and what causes it?

How do you get a blocked milk duct?

The glands that make milk in your breasts are divided into segments. A bit like an orange, in fact. Your milk ducts are the narrow tubes that carry milk to your nipple from each ‘segment’ (NHS, 2016a).

You can get a blocked milk duct when any one of your breast segments doesn’t drain properly during a feed. You might get this if your baby has a tongue-tie. It might also happen if your baby is not taking your breast into their mouth deeply enough to feed effectively – a ‘shallow latch (NHS, 2016a).

Sometimes a blocked milk duct can happen if your breast tissue is irritated for other reasons (NHS, 2016a). This might be due to wearing a bra that’s too tight or a seatbelt across your breast on a very long car journey, or an awkward sleeping position when you’re putting weight onto your breast (NHS, 2016a).

"Make sure you get your blocked milk duct sorted as soon as you can, you don't want it to turn into mastitis."

Signs and symptoms of a blocked milk duct

When you have a blocked milk duct, the area around your breast will feel hard and painful. It might also be red, warm to the touch and slightly tender (NHS, 2016a). When your baby feeds on the side of the blocked duct, they might fuss because they’re getting your milk more slowly than usual (Mohrbacher, 2010).

It’s important to relieve a blocked milk duct as soon as possible or it will lead to mastitis (an inflammation of the breast) (NHS, 2016a)

Blocked milk duct treatment

Here are some ways to try to clear a blocked duct (they also work well for engorgement and mastitis):

Carry on breastfeeding

While women sometimes get the advice to stop breastfeeding, it’s actually important to deal with the blocked duct first and carry on breastfeeding. This lowers the risk of the blockage developing into mastitis. If you were thinking of stopping breastfeeding anyway at this point, you’ll need to clear the blockage first and then stop gradually after that.

If you’re finding breastfeeding painful because of sore nipples, you might want to express milk instead for a while. But it’s also important to get skilled support so that you resolve the cause of the sore nipples.

Get your baby’s positioning and attachment checked by someone who is skilled at offering breastfeeding support

If you can’t find details of your nearest breastfeeding support group, do contact our Infant Feeding support line on 0300 330 0700. It’s open between 8am and midnight (NICE, 2015).

Other things to try include the following.

Before feeding:

  • Gently massage the breast focussing on any lumps or sore areas with your fingertips or palm of your hands (Mohrbacher, 2010).

When feeding:

  • It can be helpful to start feeding from the fuller side first, so your baby can soften the breast and clear the blocked duct.
  • Women often find it helpful to try a different feeding position. One where the baby’s chin is near the blocked duct can be helpful.

(Mohrbacher, 2010)

After feeding:

  • If your baby falls asleep quickly, or is not feeding effectively, try breast compressions and/or express after a feed.
  • Apply a cold cloth or cool gel pack after feeds.

(Mohrbacher, 2010; NHS, 2016)

In general:

  • Breastfeed or express more frequently if your breasts are uncomfortably full. Long gaps between feeds can also make a blocked duct more likely to come back.
  • Although there are no studies about this, many women find it helpful to try to break up the blockage by using an electric toothbrush. The vibrations are said to be helpful. If you haven’t got one, a wide tooth comb can work too – gently rub towards the nipple. Doing this in a warm bath or shower has been found to be effective by some women. 
  • Rest as much as possible.
  • You can take paracetamol or ibuprofen while breastfeeding. If you’re taking other medicines, do check with a pharmacist. Aspirin should not be taken by women who are breastfeeding.

(Mohrbacher, 2010; NHS, 2016)

If the lump has not cleared after a day or two, or symptoms worsen (e.g. a fever and flu-like symptoms), do go and see your GP.

How to prevent blocked milk or breast ducts

Blocked milk ducts can be prevented by doing the following:

  • Wear a well-fitted bra. Tight clothes or ill-fitting bras might restrict the milk ducts within the breast.
  • Make sure your baby is in an effective position with a deep latch. If it’s already been checked but you’re still having difficulties, do seek more support. Often, even a good latch can be improved. Your midwife or health visitor should watch a whole feed or visit your local breastfeeding support group where a skilled breastfeeding peer supporter can do this.
  • Avoid long gaps between breastfeeds or expressing

(NHS, 2016a; Healthy WA, 2018)

Milk blisters or blebs

Sometimes, a blocked duct is associated with a bleb or blister on the end of the nipple.  

These blisters look like the kind of friction blisters from wearing new shoes, or they’re filled with a bit of blood. They’re likely to have been caused by your baby rubbing or compressing the nipple against their hard palate. If you have these kind of blisters, do get support to improve positioning and attachment (Mohrbacher, 2010).

Milk blisters or blebs look like a flat patch of white on the nipple and are often really painful – although not always. Nobody really knows what causes them. It’s rare for blebs to occur in the first few days of breastfeeding but if your baby doesn’t attach well, they can appear early on (Mohrbacher, 2010).

Milk blisters that look like a slightly hardened plug can sometimes be removed by gently rubbing them with a flannel in the shower, or with a little bit of oil (Mohrbacher, 2010). Sometimes women say that the milk that had accumulated behind the blockage can flow and look a bit thickened (Mohrbacher, 2010).

If the bleb is caused by a thin layer of skin blocking one of the nipple openings, then opening it up can ease it. Don’t try this at home though as it could increase the chance of infection. Talk to your GP who might try using a sterilised needle to pierce the side or top of the blister and squeeze. This should unblock the duct and allow the milk to flow again. Make sure you keep the area clean while it’s healing (Mohrbacher, 2010).

If you are dealing with a recurring milk blister, although there is little scientific evidence behind it, many women find it helpful to soak the affected nipple in a cup or container of Epsom Salts solution. There is also some research suggesting reducing saturated fats and taking the food supplement lecithin might be helpful (Eglash, 1998; Lawrence and Lawrence, 2005; Newman and Pitman, 2006; Mohrbacher, 2010).

Mastitis symptoms

If a blocked milk duct is not cleared, it can lead to mastitis. Mastitis is a common condition that makes your breast tissue painful and inflamed. It’s most common in mums who are breastfeeding during the three months after their baby is born (NHS, 2016b) but it can happen anytime.

Symptoms of mastitis may include:

  • A red, swollen area on one breast (usually not both) that can feel hot and painful when you touch it.
  • A breast lump or a hard area.
  • Flu-like symptoms, such as aches, a fever, chills or tiredness.
  • A burning or radiating pain in your breast.
  • Nipple discharge, either white or with streaks of blood. 

(The Breastmilk Its Amazing, 2009; NHS, 2016b; La Leche League, 2016)

As well as trying the above suggestions, your GP might prescribe antibiotics (Jahanfar et al, 2013). For more information on continuing to breastfeed with, and treating, mastitis, take a look at this article.

This page was last reviewed in April 2019

Further information

We support all parents, however they feed their baby. If you have questions, concerns or need support, you can speak to a breastfeeding counsellor by calling our support line on 0300 330 0700, whether you are exclusively breastfeeding or using formula milk. Breastfeeding counsellors have had extensive training, will listen without judging or criticising and will offer relevant information and suggestions. You can also find more useful articles here.

You might find attending one of our Early Days groups helpful as they give you the opportunity to explore different approaches to important parenting issues with a qualified group leader and other new parents in your area.

Make friends with other parents-to-be and new parents in your local area for support and friendship by seeing what NCT activities are happening nearby.

National Breastfeeding Line (government funded): 0300 100 021.

Healthtalkonline.org: Managing Breastfeeding – dealing with difficult times.

Bonyata K. (2018) How do you treat a milk blister. Available from: https://kellymom.com/bf/concerns/mother/nipplebleb [Accessed 5 April 2019]

Breastmilk It’s Amazing. (2009) Mastitis. Available from: http://www.amazingbreastmilk.nhs.uk/how-to-breastfeed/mastitis/ [Accessed 1st July 2018].

Healthy WA. (2018) Blocked milk ducts. Available from: http://healthywa.wa.gov.au/Articles/A_E/Blocked-milk-ducts [Accessed 1st July 2018].

Jahanfar S, Ng CJ, Teng CL. (2013) Antibiotics for mastitis in breastfeeding women. Cochrane Database of Systematic Reviews. (2): CD005458. Available from: http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD005458.pub3/abstract [Accessed 5th April 2019]

La Leche League GB. (2016) Mastitis. Available from: https://www.laleche.org.uk/mastitis/ [Accessed 1st July 2018].

Mohrbacher N. (2010) Breastfeeding Answers Made Simple. Hale Publishing: London.

NHS Choices. (2016a) Breast pain and breastfeeding. Available from: https://www.nhs.uk/conditions/pregnancy-and-baby/breast-pain-and-breastfeeding/#blocked-breast-milk-ducts [Accessed 1st July 2018].

NHS Choices. (2016b) Mastitis. Available from: https://www.nhs.uk/conditions/mastitis/ [Accessed 1st July 2018].

NICE (2015) Postnatal care. CG37. Available from: https://www.nice.org.uk/guidance/cg37/chapter/1-Recommendations#infant-feeding [Accessed 5th April 2019]

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