Years ago, a woman traveled from Los Angeles to San Luis Obispo to see me, seeking a second opinion. The woman had been told a lesion she had on her nipple was a bleb and that this condition meant the end of her breastfeeding. She was advised to wean her baby and switch to formula. She had been experiencing repeated plugged ducts and kept picking a painful bump off the tip of her nipple, only to have it return. Nursing her baby was very painful, and she constantly felt like her breast was engorged and her milk was backed up or plugged.

Truthfully, during that time period, blebs (also known as milk blebs or nipple blebs) were rare. Now it is a condition we see much more frequently.


What is a bleb?

Most researchers agree that milk blebs are associated with inflammation of the nipple skin around the nipple pore. However, several explanations have been proposed for the cause of this irritating nipple lesion.

Dr. Katrina Mitchell, a published researcher, breast surgeon, and breastfeeding medicine specialist from Santa Barbara, California, claims a bleb is caused by inflammation deeper in the breast. The resulting inflammatory cells and bacterial byproducts migrate to the surface through the milk ducts, acting like debris that can clog the nipple opening. As a result, a hard yellow or white pimple-like lesion becomes visible. She further explains that blebs are associated and common with hyperlactation (oversupply), pumping (altered microbiome), and C-section births (altered microbiome). She doesn’t believe that the nipple anatomy and physiology support the theory that infant trauma or latch is in any way contributory to blebs (Lawrence and Lawrence, 2022) (Mitchell et al., 2022). 

Dr. Pamela Douglas—an experienced breastfeeding medicine specialist who has written and published many research papers in well-respected medical journals—takes issue with this explanation. She feels that mechanical damage and excessive stretching to the nipple skin from improper positioning (hold) while breastfeeding can cause skin rupture and inflammation. The inflammatory cells then can block a nipple pore (Douglas, 2022). Marsha Walker also agrees that nipple trauma is involved (2013). In their book, Wambach and Spencer explain that a bleb is a response to inflammation in a nipple pore, and then the skin seals over the opening (2021). Others claim that a bleb is the result of an overgrowth of bacteria (dysbiosis) or possible chronic mastitis (Mitchell et al., 2022).


What does a bleb look like?

What is a bleb - example

You may see one or several blebs, usually along the tip (face) of the nipple. Blebs may appear white or yellowish. A bleb can be confused with blisters. Blisters are larger and thinner and appear with visible clear fluid. Herpes infection of the nipple and areola may appear as a painful cluster of blisters (vesicles). Do not nurse on that nipple if herpes is suspected, as herpes is very contagious and dangerous for newborns (Lawrence and Lawrence, 2022).

Dr. Mitchell says patients may complain that “shards,” “stones,” or “pebbles” are being expressible from their nipples. She explains this is all ductal debris, similar to a storm gutter getting congested with leaves that eventually float down the stream. While uncomfortable, it isn’t harmful or dangerous. She writes, “continually expressing” these little “pebbles is not healthy for the breast tissue nor for mom’s mental health” (Mitchell, 2020). 


How I evaluate a milk bleb

When I see a patient with this complaint, the first thing we do is take a history. How long has she had the bleb? Has she had it evaluated by any other provider? What has she done to treat it? Has she been opening the bleb, peeling it, or picking at it? Is this the first bleb? Often, the lactating parent doesn’t even know she has a bleb. She may present with a “plugged duct” (inflamed area of the breast) or sore nipple. Has she been massaging, pumping frequently, and using heat or vibration?

Next, we perform a dressed test weigh. This gives us insight into the mother’s milk supply when we see how much milk the baby drinks. We examine the mother’s breasts and nipples and do a physical on the baby, looking for any abnormalities. We then observe a feeding. What does the parent’s nipple look like when the baby lets go? Commonly, I will see a baby that unlatches frequently or pulls his head way back. Usually the baby is older than 3-4 months. Babies do this for several reasons: to stimulate a slow letdown, frustration because there isn’t enough milk, pulling away because the milk flow is too much or too fast, or just because their muscles are developing and they are practicing lifting their head and chest up.


Milk bleb treatment

After ruling out any anatomical abnormalities in mother or baby, the following is our usual treatments. First, when I see a baby’s sucking or behavior is irritating the nipple, we problem-solve ways to correct it.

  1. I look at how the baby is held. Is the baby’s body close enough for baby to get a deep hold on the breast? Hips close to the mother’s ribs. Is the baby’s face close to the breast? So close baby’s lips aren’t visible?
  2. Is baby arching off the breast or pulling away? I will advise the parent to have her finger ready to break suction when baby pulls back, or tuck baby’s body close if he is arching away. This three-month-old baby was working really hard at practicing lifting her body. Her efforts kept pulling her off the breast. Tucking and holding baby’s body close was our simple correction.
  3. If the lactating parent’s milk flow is overwhelming the baby, we suggest leaning back more. I also teach the parent how to hold back the flow.
  4. If her milk supply is low or too much, we develop a plan to improve or decrease the supply so it matches baby’s nutritional needs and coordination.
  5. For a stubborn bleb ,it may help to soften the skin over the bleb by soaking a cotton ball in olive oil and wearing it against the nipple after nursing. 
  6. I suggest hand expression after each feed to make sure the bleb stays open.
  7. A short-term application of Triamcinolone ointment after nursing will decrease the inflammation. We advise that the parent wipe off any visible medication prior to nursing. Consult your medical professional for a prescription.


What if my breast feels blocked and I have unrelieved fullness?

Mitchell recommends BAIT (breast rest, Advil, ice, Tylenol) principles and to seek medical evaluation for a prescription of triamcinolone ointment to be applied directly to the bleb (Mitchell, English, and Bamberger, 2020). If the bleb doesn’t respond to conservative treatment and the area of the breast stays full and inflamed, I will advise seeking medical care to unroof (open) the bleb with a sterile needle. Douglas explains that once the milk blister is unroofed, milk is often immediately released. After that treatment, she recommends frequent feeding, making sure the feeding position has been corrected (Douglas, 2022). Frequent nursing may prevent the skin from reforming over the pore.

Once a bleb has been opened, it is important to watch for infection. Some experts recommend applying a topical antibiotic after feeds (Mohrbacher, 2020). There is controversy regarding using steroid cream as a first-stage treatment. The Academy of Breastfeeding Medicine Protocol recommends steroid cream for persistent blebs (ABM, 2022; ABM, 2019). Dr. Douglas takes issue with this advice and cautions that applying the steroid to the nipple skin could disrupt the natural protective microbiome and may over-hydrate nipple skin, potentially causing moisture-associated skin damage (Douglas, 2022). In my experience, correcting the baby’s sucking and the way the mother holds the baby while feeding, hand expression after nursing, and the topical steroid cream usually leads to resolution of the bleb.


What not to do when treating blebs

Stop any deep massage or vibration. Please do not stick needles in the area or debride (rub) it. It will only make things worse! Dr. Mitchell advises against repeatedly unroofing or opening the bleb. That will just promote more inflammation and can result in permanent scarring. Avoid squeezing the bleb; this only leads to more irritation and swelling.



White or yellow spots on nipples during breastfeeding can have a number of causes. Be aware: there is controversy on how to treat this condition. Other lesions can appear on the nipple, such as blisters or viral infections. If you see multiple clear small blisters on your nipple, do not nurse on that breast until you seek medical evaluation. Blebs can be persistent and very irritating! Be sure to see medical advice if simple home care fails to relieve your symptoms.


Photo of Andrea Herron, RN/MN/CPNP/IBCLC, pediatric nurse practitioner and the author of this post.


Check out some of our other posts on common issues encountered by breastfeeding parents!