It’s a rite of passage for many new moms who are breastfeeding: a milk bleb, also called a milk blister. These small spots on your nipple may look harmless, but they can be extremely painful, especially when your baby is nursing. The good news is that there’s plenty you can do to treat milk blebs and blisters and prevent them from developing in the future.

What is a milk bleb or milk blister?

A milk bleb or blister is a blocked nipple pore. This usually happens when a milk duct becomes clogged, causing milk to back up. Breast milk becomes thick and hard as a result, which blocks milk flow near your nipple opening. Sometimes, a small amount of skin can grow over the bleb, preventing it from healing.

Symptoms of milk blebs and milk blisters

Milk blebs or blisters usually look like a tiny white or yellow spot about the size of a pinhead on your nipple, and often resemble a whitehead pimple. The skin surrounding a milk bleb may be red and inflamed, and you may feel pain while nursing.

A milk bleb or blister isn’t the same thing as a nipple blister, which is due to irritation from a breast pump or nipple shields. These types of blisters tend to be larger, not painful and go away once the problem is corrected.

Milk blebs also shouldn’t be confused with thrush, a fungal infection that forms on the nipples or breast and can cause severe burning and pain when nursing. With thrush, nipples often look shiny and red with multiple white patches. Thrush usually requires prescription anti-fungal meds for both mom and baby.

What causes a milk bleb or blister?

  • Poor latch. Latching incorrectly may prevent your baby from fully emptying your breasts. This can cause milk to build up and plug your nipple ducts.
  • Tight-fitting bras, underwire bras or sleepwear. These can irritate your nipples, and contribute to milk blister formation.
  • Milk oversupply. If you produce more milk than your baby can effectively drain, it can get backed up and clog ducts.

How do you treat a milk bleb or blister?

Most of the time, you don’t have to do anything, and the milk bleb will go away on its own within about 48 hours. But if it hurts, there are a few ways to find relief.

  • Apply a warm wet washcloth for 10 to 15 minutes.
  • Nurse your baby. The act of suckling may actually open the blister. Try positioning your baby so that his chin is near the plugged area, because this positioning can help drain that area best.
  • Talk with your OB/GYN or lactation consultant about taking a pain reliever, such as acetaminophen (Tylenol and others) or ibuprofen (Advil and others). Also, consult with them before attempting to open the blister yourself. They may advise you to visit their office so that they can drain it using a sterile needle. Once it’s open, you should wash it daily with mild soap and water and apply an over-the-counter or prescription antibiotic ointment to the area to help prevent infection.

If these steps don’t work after about two days or you become concerned, call your doctor. If left untreated, a blocked duct can become infected, leading to a condition known as mastitis.

How do you prevent future milk blebs or blisters from developing?

  • Position your baby correctly. You want to make sure your baby is latched on properly, so that his mouth forms a tight seal around the nipple and most of the areola (the dark skin around the nipple). Try holding your baby at the side of your body (the football hold) or across the front of your body (the cradle hold). Vary your position during feedings so every part of the breast gets emptied. You can also try hand expressing or pumping your breast after each nursing session to improve drainage.
  • Clean your nipples. After nursing, wipe your nipples with a moist cloth to help prevent clogged pores.
  • Drink plenty of fluids. Dehydration doesn’t just decrease your milk supply — it also may raise your chances of developing a clogged milk duct that in turn can cause a milk bleb.
  • Pump at night if it’s necessary. Sometimes, a baby who suddenly starts sleeping through the night can lead to clogged ducts or milk blebs. This may allow you to get much needed sleep, but it can also leave you with very full breasts. Pumping at least once — even just right before you go to sleep — can help prevent milk blisters from forming.