Can I take herbal supplements while breastfeeding?

The verdict

Mostly not, and this is one of the few categories where the NHS uses the phrase not recommended without qualification. Its reason is not that herbal remedies have been shown to be harmful. It is that not enough is known about them to guarantee they are safe.

The Breastfeeding Network takes the same line and adds specifics: herbal supplements are generally not recommended while breastfeeding because there is not enough information on whether they pass into breastmilk and what effect they might have. healthdirect Australia says that for most herbal and traditional medicines there is not enough research to check safety in lactation.

Why herbal is not the same as harmless

The intuition that a plant extract must be gentler than a pharmaceutical does not survive contact with the pharmacology. Herbal preparations contain active compounds; that is why people take them. Those compounds are absorbed, metabolised and excreted like any other, and some of them are potent.

St John's wort is the clearest illustration and the Breastfeeding Network singles it out. It has potent effects on other medicines, will stop most hormonal contraception working properly, and may affect other prescribed drugs. That is not a gentle profile. The Breastfeeding Network's conclusion is that alternative medicines exist which are carefully monitored and have more evidence behind them, and are preferred.

What is different about a pharmaceutical

The gap is regulatory rather than botanical. A licensed medicine has a known quantity of a known compound in every dose, and a body of measurement behind it. A herbal supplement often does not. The NIH notes that dietary supplements do not require pre-marketing approval, that manufacturers are responsible for safety without having to demonstrate it first, and that products may contain multiple ingredients that vary between them. That is why specialist services can give you a clear answer about paracetamol and cannot give you one about a blend.

The named avoid list

The Breastfeeding Network publishes a specific list of remedies that are not recommended while breastfeeding, because they have limited or no evidence of use and may pose a risk to milk supply or of side effects in a breastfed child. It includes ashwagandha, ginseng, ginkgo biloba, black cohosh, black snakeroot, kava kava, ephedra, guarana, dong quai, uva ursi, buckthorn, bladderwrack, tiratricol and two species of wormwood.

Ashwagandha and ginseng deserve particular mention because they are heavily marketed for stress and fatigue, which is precisely what new parents have. Guarana is a common ingredient in energy products and is a caffeine source in its own right. Recognising the names on a label is more useful than any general principle.

The ones with a qualified yes

Not everything botanical is on the avoid list. The Breastfeeding Network's supplements factsheet includes a longer list of individual items with references, covering things such as ginger, turmeric, peppermint, evening primrose oil, echinacea, glucosamine, lecithin and coenzyme Q10, drawn from e-lactancia and LactMed entries. It notes separately that prebiotics and probiotics are not absorbed into the body and are considered compatible.

Two are worth flagging for reasons other than the baby. Valerian, found in several herbal sleep products, causes drowsiness, which the Breastfeeding Network notes may affect your ability to respond to your baby and the safety of bed-sharing. Thyme extract, found in some herbal cough syrups, is not recommended because some sources suggest it may reduce milk supply.

Supplements taken to increase supply

Galactagogues are the herbal question that arises most often in breastfeeding, and fenugreek is the usual candidate. The Breastfeeding Network keeps a separate factsheet on the use of galactagogues rather than answering it inside its general supplements advice, which is itself a signal that the question is more complicated than a yes or no. Low supply usually has a mechanical or management cause, and a herb is a poor substitute for an assessment of how feeding is going.

Multi-ingredient blends

The Breastfeeding Network's most repeated sentence across its supplements material is that it has no evidence for herbal or health remedies containing multiple ingredients, and that its service cannot look up long lists of actives because the data do not exist. Sleep blends, immunity blends, greens powders and postnatal recovery formulas are all in this category. A single-ingredient product can at least be checked; a proprietary blend cannot.

What to watch for

Because these products are unassessed rather than assessed and cleared, the sensible approach is to notice changes rather than to expect specific ones. Any change in your baby's feeding, sleepiness, irritability or stools after starting something new is worth a call, and so is any change in your own supply. healthdirect adds the reminder that herbal products can interact with prescription medicines, so mention them when you are asked what you are taking.

Who to ask before you take it

If you want an answer about your own situation rather than a general one, the UK has a service for exactly this. The Drugs in Breastmilk service, run by the charity The Breastfeeding Network and staffed by pharmacists, answers questions about specific medicines and specific babies. NHS prescribers use the Specialist Pharmacy Service and its UK Drugs in Lactation Advisory Service, so your GP or pharmacist can escalate a question you cannot resolve at the counter. In the United States the equivalent public reference is LactMed, the drugs and lactation database published by the National Institute of Child Health and Human Development, alongside the MotherToBaby counselling service. In Australia, healthdirect points to a pharmacist advice line and the Australian Breastfeeding Association helpline. In Ireland the HSE tells you to ask your GP, pharmacist, lactation nurse or midwife before taking any medicine, herbal remedy or supplement.

If you have already taken something on the avoid list, that is a question rather than an emergency, and the Drugs in Breastmilk service is the right place to put it.