We don’t have good data on the proportion of women with breast milk supply issues, but it is a commonly reported reason for stopping breastfeeding and/or starting formula.
For women who suspect they have low breast milk supply, the first thing to do is get some breastfeeding support. A lactation consultant or other specialist can provide practical help with attaching the infant on the breast, and guidance on strategies to stimulate supply, such as increasing the frequency of breastfeeds or using a breast pump.
If the supply problem persists, you may be offered the prescription medication domperidone. This is the most effective and commonly used drug to boost milk supply.
How does domperidone work?
A key hormone involved in controlling breast milk production is prolactin. Domperidone works to raise levels of prolactin, which helps increase the production of breast milk.
Domperidone is usually started at a dose of 10 milligrams (one tablet) three times a day. Breast milk supply should start to improve within seven days and peak at two to four weeks.
If supply remains low, there is some evidence – though weak – that doubling the dose may help. But this should only be done under careful medical supervision.
Once adequate breast milk supply is reached, the dose should be slowly reduced to avoid a drop in milk production.
How effective is it?
Most studies have investigated the effects of domperidone in mothers following preterm birth (birth at less than 37 weeks’ gestation) where their baby is admitted to a hospital neonatal unit. In these settings, domperidone was associated with a short-term increase in daily milk production of 90 millilitres per day.
We assume domperidone works just as well in mothers with a full-term birth, but there’s no evidence to prove this.
Also, there’s some evidence domperidone may work better in some women than others. This means not all women taking domperidone will experience the same increase in breast milk volume. And some may get no benefit at all.
What are the risks?
Side effects are uncommon but include headaches, abdominal pain, dry mouth and, even less commonly, a rash or trouble sleeping.
Domperidone has received negative press in recent years because of concerns it can change the rhythm of the heart, a concept known as QT prolongation. By altering the rhythm of the heart, domperidone has the potential to cause a potentially life-threatening side effect known as ventricular arrhythmia, or rapid heart rate.
Previous studies have shown those at most risk from this rare side effect were male, older than 60 years of age, taking other medications that can also cause the same effect on the heart, or had a previous history of an abnormal heart rate. So the relevance of these concerns to young and otherwise healthy lactating women has been questioned.
The cardiac safety of domperidone when used in breastfeeding has only been looked at in one study, from Canada. Researchers investigated 45,163 women using domperidone in the six months after giving birth. A total of six women who took domperidone were hospitalised for ventricular arrhythmia (a rapid heart rate). This is 1.3 per 10,000 women.
Looking more closely into the study results, all cases of ventricular arrhythmia occurred in women who had a previous history of ventricular arrhythmia. Among 45,163 women using domperidone who had no previous history of ventricular arrhythmia, no cases were observed.
This study provides reassuring evidence of the safety of domperidone in women who have recently given birth, and also highlights the importance of women discussing any heart conditions with their doctor.
No side effects have been found in infants whose mothers use domperidone. The amount of domperidone found in breast milk is extremely small, with infants exposed to less than 0.02% of the total dose.
What about metoclopramide?
Domperidone belongs to the same family of medicines as metoclopramide and works in a similar way. But they have very different side effects. Metoclopramide can cause central nervous system side effects such as fatigue, irritability, or depression.
Side effects are much less likely with domperidone, so it’s the preferred medicine to boost breast milk supply.
Are herbal medicines as good?
In recent years, interest has grown in whether herbal medicines – such as fenugreek, milk thistle, blessed thistle and ginger – can boost milk supply.
Herbal medicines are popular because they can be purchased without the need to see a doctor and get a prescription. They may also seem safer and more “natural” than prescription medicines.
But the evidence does not appear to match enthusiasm for their use. There is no good quality evidence these medicines work, with most supporting evidence coming from case reports or very low quality studies or those based on historical use.
There is, however, evidence they could cause side effects, interact with other medicines, or interfere with other medical conditions.
While some women might find benefits in using herbal medicines, they should not be seen as an alternative to evidence-based treatments and should only be used after discussion with a health care professional.
Photo credit: Alex Pasarelu