Milk Bleb: What It Is and How to Treat It

What is a milk bleb?

A milk bleb (also called a nipple bleb or “milk blister”) is a small yellow, white, or clear bump that can appear on the nipple and indicates an inflamed milk duct that is blocking a nipple pore (the tiny opening where milk exits the breast). Milk blebs can be very painful, often with sharp or shooting pains that start during or after feeds.

What causes a milk bleb?

While many people believe a bleb comes from some milk getting stuck in a milk duct, it’s actually caused by inflammation. 

Common contributing factors include:

• Inflammation or narrowing of the milk ducts that can push inflammatory material to the nipple surface.

• Making too much milk (oversupply), which can lead to congestion and inflammation.

• Problems with how baby is latching or transferring milk (not draining the breast well), changes in feeding routines, or long times between removing milk, which can lead to milk duct congestion and inflammation.

• Sometimes blebs appear along with mastitis or other inflammatory nipple conditions (a healthcare provider should check for these).

Milk bleb vs. thrush

Thrush is a yeast infection caused by Candida albicans, and it can affect both the breastfeeding parent’s nipples and the baby’s mouth. Symptoms include burning, itching, or deep stabbing breast pain; the nipples may look pink, shiny, flaky, or cracked; and often both breasts are affected. The breastfeeding baby may have white patches inside their mouth that don’t wipe off, a diaper rash, or be extra fussy during feedings. Thrush is an infection and can pass back and forth between parent and baby.

Treatment for thrush includes antifungal medication for both parent and baby, while breastfeeding continues without disruption. If you suspect you and/or your baby have thrush, consult your medical provider. 

How to treat a milk bleb

Don’t: Try to pop the milk bleb or “unroof” it. This can traumatize the nipple and worsen the inflammation, which can cause scarring or can lead to the bleb coming back. Digging or opening the skin covering the pore can also increase tissue trauma and infection risk.

Instead: Reduce inflammation by…

• Applying cold compresses after feeds (for around 10–20 minutes)

• Taking NSAIDs (e.g., ibuprofen), if medically appropriate

• Avoiding vigorous massage or squeezing (can worsen inflammation)

And focus on removing milk as normal from the breast by…

• Continuing to breastfeed

• Feeding responsively and avoiding “over-pumping” to try and empty completely

• Optimizing baby’s latch and positioning

• Avoiding tight bras or pressure on the breast

If a bleb doesn’t go away on its own, a clinician may prescribe a steroid cream to reduce localized inflammation

When to get medical help urgently

Contact your medical provider if you have:

• Fever and/or chills, rapidly spreading redness, worsening swelling or pain, or symptoms not improving within ~24–48 hours

• A recurrent bleb in the same spot, significant nipple trauma, or severe pain impacting feeding