Milk Crusts: Caked Nip and Exclusive Pumping

by Ashton Fortin Higgins, PhD, CLC, cALS, ACS

What is Caked Nip?

Have you ever noticed milk crusts forming on your nipples? They may be hard to remove and prominent whether you are currently pumping or after a pump session.

This crust is not always healing from cracks or bleeding that occurs from a wound. When a wound heals, it looks more like a scab, brownish/red in colour. The caked nip is white/cream in colour. If you were to touch the area and if it would peel off, it can almost look like a tough dandruff. Caked nip is not a random nipple discharge or weeping that crusts up on the nipple, it is essentially left over milk mixed in with other elements.

What Do We Know About Caked Nip à la Research? (For Pumpers and MDs)

There are only a few studies out there that actually talk about milk crust on nipples that relate to caked nip in the way exclusive pumpers are prone to this condition. Sadly, with small sample sizes. What is important to note is that this is NOT THRUSH. Thrush is often over-diagnosed, misdiagnosed [1,2], and rare in exclusive pumping as we are not direct latching. Prescribing nyastin and fluconazole will not clear up milk crusts. If you are a health care provider working with an exclusive pumper, I strongly encourage you take a swab and test for yeast before jumping to a thrush conclusion. There has been some evidence that medications such as Azithromycin and Erythromycin, or even probiotics have been helpful in treating nipple conditions instead of nyastin/fluconazole among individuals originally thought to have a yeast/thrush diagnosis [2]. If you have a patient that has been using nyastin/fluconazole for over a month with no improvement, it's time to further investigate. Many exclusive pumpers will consider weaning should there be no improvement to chronic nipple pain. Our ultimate goal should be human milk for infants as long as it is possible for the lactating individual to do so, where nipple pain should be taken seriously.

Due to chronic breast pump use, exclusive pumpers do not get exposure to infant saliva that would essentially help get rid of this milk crust [2]. There's also a hypothesis that this is related to hyperlactation [3], which would further need to be investigated. Personally having experienced milk crusting as a just-enougher, anecdotally, leads me to believe that any exclusive pumper with lack of infant saliva exposure to remove any nipple debris could have caked nip. Milk crusts are not pathologic, but can warrant further investigation should one be experiencing pain that can may be associated with hyperlactation (such as an oversupplier) or mammary dysbiosis (unbalanced microbes at the nipple/areolar area). It would be wise to seek the help of an MD who is also an IBCLC if possible, several can be found through Academy of Breastfeeding Medicine, or through a lactation specialist such as an IBCLC or cALS in your community who specializes in exclusive pumping.

Caked Nip Treatment, What are our Options? (For Exclusive Pumpers)

Unlike an easy shampoo solution for dandruff, caked nip can remain on your nipple for a long time, in some cases years. One study indicated their milk crust client was instructed to stop pumping and to avoid attempts of eliminating the crust for fear of more harm than good [2]. It's worth noting that this individual also was being treated for a perinatal mood anxiety disorder as well, so their reason for discontinuing pumping may be related to their PMAD and/or their nipple pain/milk crust [2].

For the majority of us, the want to continue to pump will be stronger than wanting to stop pumping, meaning we could have caked nip for a while. One solution is to use a similar treatment as removing milk blebs, the saline soak. Using a warm cloth to remove the milk crust debris after the soak can be helpful. I know the urge to pick at it may be a quick fix, but it could cause an additional nipple pain if too much is removed and there's now an open wound present on the nipple. It's worth noting that if caked nip isn't bothering you, the recommendation is that you do not attempt to remove the crust repeatedly [2].

I'm an Exclusive Pumper, Can I Avoid Caked Nip?

The data on exclusive pumping is slim in general. In fact, these studies used small sample sizes and it's difficult to say the prevalence of getting milk crusts as an exclusive pumper. In my practice I will note that milk crusting is extremely common, and for the most part not impacting quality of life. If it's causing you pain, please seek help. What is even less known is how common caked nip can be prevalent post weaning, which would be one less desirable outcome of pumping. More research is needed! However, in my opinion, the benefits of providing human milk to infants outweigh that of not providing any human milk at all, no matter how long in duration.