The Truth About Breastfeeding

The symptoms associated with thrush (a candida yeast infection) in breastfeeding women vary. Some have red or shiny nipples, fissures or flaking skin, others exhibit no visible signs at all¹. There is one symptom, however, that is reported almost universally: pain. It is usually described ‘in the strongest terms, with words such as “agonizing” or “excruciating” often being used’, and can occur throughout a feed and continue for sometime afterwards². Faced with this level of discomfort, it is not surprising that many mothers diagnosed with thrush feel unable to continue breastfeeding^3,4.

This shouldn’t be the case, of course; fungal infections are highly treatable, so contracting one need not automatically spell the end of breastfeeding. Unfortunately, getting medication for this type of thrush isn’t always straightforward, particularly if you are unlucky enough to have an unsympathetic doctor (see breastfeeding and thrush: it’s complicated). Health professionals who are reluctant to diagnose thrush, are naturally hesitant to prescribe for it, so some mothers may be left suffering unnecessarily, or given the wrong medication, such as antibiotics, which may actually make the condition worse².

An additional problem is that the evidence base for treating breastfeeding yeast infections is sorely lacking. Although there are many antifungal drugs available, there have yet to be any controlled clinical trials examining their effectiveness for treating a candida infection of the breast. The difficulty confirming a diagnosis may be one reason for the lack of trials: milk and skin cultures aren’t always reliable, so it could be difficult to know whether a treatment failed because the drug was ineffective, or because the symptoms weren’t actually caused by candida. Alternatively, it may be because this research simply isn’t viewed as a priority: if an infection is caused by candida, then it should clear up eventually providing enough antifungals are thrown at it⁵. This ignores the possibility that the unique environment breasts are subject to during nursing may impact on the effectiveness of a treatment, but at present it’s the most ‘scientific’ approach we have.

Case studies and anecdotal information sources (which generally consist of health professionals giving opinions based on their clinical experience) also offer theories about the best way of treating thrush. A traditional medication for nipple thrush recommended on numerous breastfeeding websites (albeit mostly in articles written by the same person) is gentian violet, a purple ointment that can be applied to both nipples and babies’ mouths. Although there are no controlled clinical trials supporting its use for nipple thrush, it is known to be an effective antifungal, and there is anecdotal evidence it can be helpful for breastfeeding women². Gentian violet does have its drawbacks, however. A minor issue is that it is messy (it is used as a dye); a more serious concern is that it can cause skin irritation⁶ and may be carcinogenic⁷, and as such it is not available for this purpose in the UK.

Due to the lack of clinical research in this area, there is no definitive list of drugs that are suitable for treating thrush in breastfeeding women, so theoretically any medication that is antifungal and unlikely to cause problems for a nursing baby could be prescribed. Common topical treatments include miconazole and clotrimazole, which are usually supplied in creams or powders. These are not advised for internal use, so it is generally recommended that they are removed before breastfeeding, although this is due to the ingredients in the base of the medication, rather than the antifungals themselves (both can be used to treat oral thrush if they are supplied in the appropriate preparation). Nystatin can also be applied topically to the nipples and is usually supplied in a formulation that does not need to be washed off. It is often used for treating thrush in babies’ mouths, and as such is often the first medication suggested for treating mothers too⁵.

Anecdotal evidence suggests that topical treatments aren’t always effective, however, and thrush can be treated more reliably with fluconazole^5,8 (a clinical study suggests that this is the case for oral thrush too⁹.) Unlike creams and ointments that only treat the skin where they are applied, fluconazole has the additional advantage of being taken internally, providing a blanket assault on candida wherever the site of infection.

Although organizations like the Breastfeeding Network and the NHS suggest that fluconazole is a good treatment for mothers who appear to be suffering from persistent thrush, it can pass into milk in small amounts, and is not currently licensed for use when breastfeeding. As it can be safely given to newborns, this is not a great concern. The fact that the breastfeeding box isn’t officially ticked can make doctors cautious, however, leaving some women without potentially important medication. The opinion that fluconazole shouldn’t be given to breastfeeding women unless it is part of a controlled clinical trial can also be found in the scientific literature¹⁰, and while this idea is reasonable in theory, until someone actually gets round to running the trial, it isn’t so great for those women experiencing ‘intolerable and incredible pain’ that may be due to thrush¹¹.

At present, there isn’t any concrete evidence that fluconazole (or indeed, any medication) is suitable for treating yeast infections in breastfeeding women, because there haven’t been any controlled clinical trials looking at its use in this situation. Until such trials are conducted, there are a couple of options. One is to deny women antifungal medication on the grounds that there is no proof it works. An alternative – supported by numerous breastfeeding organizations – is to advise women with suspected thrush to take fluconazole orally, to treat nipples topically and ensure their babies’ mouths are treated too, in the hope of alleviating symptoms. Proper research in this area would naturally be a great step forward, but until it occurs (if it ever does), it seems only fair to offer women suffering very painful symptoms at least a chance at respite, particularly if it enables them to continue breastfeeding.

1. J Hum Lact. 2004 Aug;20(3):288-95.
2. Aust N Z J Obstet Gynaecol. 1991 Nov;31(4):378-80.
3. J Obstet Gynecol Neonatal Nurs. 2005 Jan-Feb;34(1):37-45.
4. Clin Pediatr (Phila). 2001 Sep;40(9):503-6.
5. J Hum Lact. 1999 Dec;15(4):281-8.
6. J Hum Lact. 1990 Dec;6(4):178-80.
7. Fundam Appl Toxicol. 1985 Oct;5(5):902-12.
8. J Hum Lact. 2002 May;18(2):168-71.
9. Pediatr Infect Dis J. 2002 Dec;21(12):1165-7.
10. Breast. 2002 Feb;11(1):88-90
11. J Hum Lact. 1997 Dec;13(4):307-11.