Thrush is the name for a yeast infection caused by an overgrowth of a fungus, usually Candida albicans. C. albicans is normally kept in check by friendly bacteria in our bodies. A baby can get thrush inside his mouth (seen as white patches that don’t wipe away) or in his nappy area (an inflamed nappy rash) and under certain circumstances it is thought that a breastfeeding mother can get thrush on her nipples causing pain and soreness. The symptoms of thrush on nipples can be very similar to the symptoms experienced with a bacterial infection of the nipple or when a baby is not latched correctly—causing pinching or vasospasm of the nipple. This makes diagnosis very difficult and there is some controversy over the condition 1. This article looks at the symptoms, causes, and treatments traditionally associated with a diagnosis of thrush on nipples.
Symptoms of thrush
Although there may not be any visible symptoms to see in mother or baby the most common symptoms during breastfeeding that are assumed to be a thrush infection are said to be:
- Itching or burning pain, especially after breastfeeds
- Nipples may feel very sore and sensitive to touch and nipple skin and areolae may appear deep pink, flaky or shiny. Sometimes tiny blisters are present 2.
- There may be a loss of colour in the nipple or areola 3
- Pain will usually be in both nipples at the same time because the baby transfers the infection from one nipple to the other
- Pain may worsen as the feed progresses and be felt for several minutes or for hours after a breastfeed
- Pain may be felt deep in the breast, sometimes as a stabbing pain and sometimes in the back and shoulders 4
- Baby may have white patches of fungal growth inside his cheeks, or on his gums or tongue which don’t rub off. When this makes your baby’s mouth sore he may find feeding painful and appear fussy.
- Baby may have a sore bottom and nappy rash
Sudden onset of symptoms
In their handout The National Infant Feeding Network suggest that if symptoms fitting the description of thrush come on suddenly after pain free breastfeeding, or if pain continues even after latching and positioning help from a breastfeeding specialist, thrush could be a possibility 5. For more information on diagnosing thrush see below.
Thrush or some other cause?
The symptoms listed above can be difficult to distinguish from other causes of sore nipples such as nipple vasospasm from a poor latch, a bacterial infection, dermatitis or eczema. Even a white tongue for your baby may have other causes for example a white coating on the back portion of the tongue has been associated with poor tongue function. In addition, symptoms of deep breast pain can be difficult to separate from mammary constriction syndrome which is also associated with poor latch and positioning. Jiménez et al 6 believe mammary candidiasis (breast thrush) lacks scientific evidence as a medical condition and propose an alternative explanation (see below).
Causes of thrush
The fungus Candida albicans and other Candida species generally live on our bodies without causing a problem. In warm, moist areas, such as inside your baby’s mouth or on breastfeeding nipples, it is thought to have the potential to grow to problematic proportions under certain conditions. However the precise role of Candida versus other organisms in the breast may not be straightforward 7.
The ideal conditions thought to be risk factors for thrush overgrowth include:
- If a mother has cracked, damaged or sore nipples
- If mother or baby have another illness or low resistance to infection or have received antibiotics or corticosteroids 8. Antibiotics can change the balance of microorganisms by killing the friendly bacteria that help keep thrush in check.
- If mother or a family member has an existing Candida fungal infection such as vaginal thrush, athlete’s foot, nappy rash or jock itch 9
- Frequent use of lanolin as a nipple cream may be associated with fungal infections see Treatments for Sore Nipples for more information about using lanolin.
- Mother takes oral contraceptives 10
- Using a dummy/pacifier or bottle teat especially in the early weeks after birth (these are a source of reinfection) 11
- Mother has diabetes and/or anaemia (low iron levels) 12
- Recurring blocked milk ducts (Newman, 2014)
- If a mother is exhausted or stressed 13.
Thrush or subacute mastitis?
Jiménez et al 14 have identified specific strains of bacteria that can overgrow under certain conditions. They argue that these bacteria do not produce the toxins seen with Staphylococcus aureus (the bacteria most often associated with mastitis) and therefore they do not trigger the flu like symptoms and flushing of the breast of classic mastitis. However they can cause inflammation in the ductal system which narrows the ducts and this could be the cause of the characteristic shooting and burning pains often assumed to be thrush. These researchers favour calling this condition subacute mastitis rather than mammary candidiasis.
As there are many other potential causes of the symptoms associated with thrush, it is important to rule out all possibilities. An IBCLC lactation consultant can help rule out positioning as a cause of thrush-like symptoms and your health professional will advise which of a bacterial or fungal infection (or both) is most likely.
There is a growing concern that thrush is over diagnosed. Jack Newman, MD, Canadian paediatrician and breastfeeding expert, explains:
Many mothers are being treated for Candida albicans when they don’t have it. If the mother took antibiotics, if the baby has thrush, or even if “we tried everything else,” she may be treated for Candida but not actually have it.
The Breastfeeding Network (BFN) are also very concerned about over diagnosis of thrush. Wendy Jones PhD, MRPharmS and the BFN have developed a fact sheet 15 and a diagnostic tool 16 to try to help mothers self-diagnose if they have thrush. The article Causes of Sore Nipples may also be helpful.
To swab or not to swab
On their website, The Breastfeeding Network recommend swabbing nipples 17 to check whether an infection is bacterial (Staphylococcus aureus) or fungal (Candida) before treatments are prescribed. Conversely the latest guidance on thrush from The National Infant Feeding Network (NIFN) says swabs are not usually required unless a bacterial infection is suspected, a treatment isn’t working or if systemic treatment—eg a prescription medicine rather than a topical cream—is considered 18.
Fungal or bacterial infection?
The NIFN thrush statement also points out that at least half of all breastfeeding women have the bacteria Staphylococcus aureus (S. aureus or staph) on their nipples, often without symptoms, and therefore a mother may have both staph and Candida on her nipples. It also states that charcoal skin swabs may only pick up about 10% of Candida infections, and that it is hard to identify Candida in human milk because of lactoferrin 19. However, Jiménez et al maintain Candida species can be easily isolated in the laboratory when they are present in milk.
Most breastfeeding resources discuss how a mother and baby can pass a thrush infection back and forth between them unless both are treated at the same time. Places with the latest guidance on thrush treatments to discuss with your doctor include:
#1 National Infant Feeding Network statement on thrush
The National Infant Feeding Network (NIFN) has funding from the Department of Health (UK) and is supported by Unicef UK. The NIFN statement on thrush is available to download from the Unicef website, and describes the following treatment:
The treatment of choice for topical thrush is Miconazole (Daktarin) cream (2%) applied sparingly to the mother’s nipples after every feed.
If nipples are very inflamed, hydrocortisone (1%) as well. A combination cream or ointment (Miconazole 2% with hydrocortisone 1%) may also be used.
Second line treatment: Fluconazole 150–300 mg as a single dose followed by 50–100 mg twice a day for 10 days. Continue topical treatment in both the mother and the infant.
Persistent or systemic/ductal Candida may require longer (14 – 28 days) treatment.
National Institute for Health and Care Excellence (NICE) guidelines for treating thrush 20 are very similar.
#2 Breastfeeding Network’s information sheet on thrush
The Breastfeeding Network is a breastfeeding charity in UK, their information sheet written by pharmacist Wendy Jones discusses other causes of nipple pain that are mistaken for thrush, self-help measures, and treatment options for mother and baby.
#3 Candida protocol (Dr Jack Newman)
Jack Newman, Canadian paediatrician, describes the slightly different treatments he recommends in his Candida protocol below:
NOTE this protocol advocates using gentian violet. Gentian violet is very irritating in high concentrations and could lead to oral ulceration and skin reactions 21. Wambach and Riordan (2015) caution that as other antifungals are available with fewer side effects, gentian violet should only be used with extreme caution.
Treatment for babies and children
For a detailed protocol for suggested treatment of thrush in babies and children from 0 months to 12 years, refer to Treatment of Oral Candida in Children (NICE, 2013).
More treatment ideas
- Continue to breastfeed if you or your baby have thrush, breastfeeding can help the growth of bacteria such as Lactobacillus which can limit fungal growth 22.
- Observe strict hygiene, wash hands well after nappy changes 23. Wash and sterilise nipple shields, dummies, teats, and toys that are put in baby’s mouth.
- Consider treatment for bacterial infection if symptoms persist alongside topical treatments 24 Staph infections are associated with cracked nipples and may be present at the same time as thrush 25.
- Treat mother and baby at the same time to prevent recolonisation 26. Treat sexual partners also (Wambach and Riordan, 2015).
- Reduce excess sugar and other refined carbohydrates in mother’s diet e.g. reduce sugar, honey, alcohol, cheese, wheat, bread 27.
- Probiotic bacteria such as Lactobacillus acidophilus may help reestablish a normal flora 28 so that mother will be resistant to infection however more research is needed ( see Mastitis Symptoms and Treatment for more information on probiotics).
- Other supplements may be helpful see La Leche League Great Britain’s information sheet Thrush and Breastfeeding for suggested dietary supplements (grapefruit seed extract, garlic, zinc and B vitamins) that some mothers have found helpful. The fact sheet includes suggested doses.
- If possible keep nipples dry, change breast pads often, wear cotton underwear, and use hot washes for washing underwear to kill fungal spores 29
Persistent thrush and fluconazole
The ideas above are said to help eradicate thrush and Wambach and Riordan comment that in persistent cases, fluconazole (a prescription antifungal drug) could be prescribed for both mother and baby. They note that the amount of fluconazole reaching the baby via breast milk from treating the mother alone, would be insufficient to treat the baby. However, pharmacist Wendy Jones cautions that fluconazole has a long half life (88 hours) in babies under six weeks of age and daily treatment of the mother could accumulate in the younger baby 30.
For further information about fluconazole use for babies see the NICE guidelines Treatment of Oral Candida in Children. And for more information about fluconazole during lactation see Lactmed, Medsmilk [paywall] and e-Lactancia and discuss treatment options with your health care provider.
Persistent thrush, NOT thrush?
If the medications suggested in the above protocols—or alternatives recommended by your health professional—do not work, consider that the cause of your sore nipples may not be thrush after all. Unnecessary treatment is also associated with vasospasm symptoms.
Nipple vasospasm may sometimes feel like a thrush infection of the nipple or breast. If you are prescribed Fluconazole/Diflucan for thrush, but your real problem is nipple vasospasm, this treatment may make your vasospasm worse.
Can I store breast milk during a thrush episode?
Freezing breast milk containing Candida will not kill the fungal cells and it is not clear whether feeding milk expressed during a thrush episode could cause reinfection. Nancy Mohrbacher says:
Research indicates that freezing does not kill yeast, but no one is sure if expressed milk can cause a recurrence. Suggest the mother give the baby any milk that was expressed and stored during a thrush outbreak while they are being treated. If that is not possible or practical, suggest she boil the milk to kill any yeast before giving it to the baby.
The Academy of Breastfeeding Medicine’s protocol indicates there is no evidence that milk need be discarded during a thrush episode.
If a mother has breast or nipple pain from what is considered to be a bacterial or yeast infection, there is no evidence that her stored expressed milk needs to be discarded.
Thrush is a fungal infection that, under certain conditions, is thought to develop on nipples during breastfeeding causing pain and soreness. The symptoms are very similar to those caused by a poor latch or a bacterial infection of the nipple making accurate diagnosis difficult. There are a number of treatment protocols for thrush including topical antifungal creams, careful hygiene, dietary changes and antifungal medications. However, if thrush doesn’t resolve with treatment, perhaps it isn’t thrush! New research offers an alternative theory for some of the symptoms of breast thrush involving infection by certain strains of bacteria. Your IBCLC lactation consultant can help you identify whether there are other causes for your painful nipples such as poor positioning or attachment, and your health professional will advise whether a bacterial infection could be present.