Herbs and Breastfeeding

Ruth A. Laurence, M. D. Professor of Pediatrics, Obstetrics & Gynecology University of Rochester School of Medicine & Dentistry

Herbs are marketed as natural remedies to cure many ailments, including sleeplessness, depression, and cardiac disease. Herbs come in natural forms (i.e. roots, leaves, flowers, seeds, and berries), and can be purchased at almost every supermarket, health food store, and over the Internet. Herbal teas, such as peppermint tea, are very pleasant tasting and are often sipped to relax. Many well-known brands of vitamins and food supplements also contain herbs.

Although herbs are natural, they are not always safe, especially for breastfeeding mothers. Many herbals contain ingredients that have effects similar to certain medications that pass through the breastmilk and potentially could be dangerous to a nursing mother and her infant. The compounds coumarin and nicotinic acid found in fenugreek, for example, can have very potent effects on heart rate, blood pressure, blood sugar, and other bodily functions. If a mother consumes fenugreek regularly in large amounts, her baby can experience these symptoms as well. Because the effect and concentration of different herbs found in teas, liquids, pills, and food supplements may vary, breastfeeding mothers should be cautious and selective in their use of any herbal preparations.

The Lack of Regulation of Herbal Preparations

There are no rules or regulations for the distribution of herbs, making it difficult for consumers to distinguish safe versus potentially dangerous herbal preparations. The Food and Drug Administration (FDA) is mandated to control the safety of all medications and infant formula in the United States, but herbs are not included in this definition. Because herbal preparations are not regulated by the FDA, there is no requirement to list the ingredients of such preparations on the label. Perhaps more dangerous is the fact that many herbal preparations list some of the ingredients, but not others that may be potentially dangerous.

There also is no requirement to list the dose of active ingredients found in herbal preparations. Because herbs occur in natural forms, rather than being carefully measured in a laboratory, the amount of an active ingredient may vary from leaf-to-leaf or from plant-to-plant. This is particularly important when using potentially dangerous herbs, such as the leaves of the foxglove plant that were once prescribed to treat heart failure. When leaves of the foxglove plant, which contain digitalis, were ground up and rolled into pills, one pill was not the exact same strength as another, making it extremely difficult to control the dose of the herbal and its effect on the disease. Fortunately, in our modern-day pharmaceutical industry all medications are carefully measured and tested for quality in the laboratory before being distributed to the public.

Nonetheless, new mothers should be aware of herbs that are safe (and maybe even beneficial) while breastfeeding, and what herbs should be avoided.

Breastfeeding Mothers Can Enjoy Many Herbal Teas

Many herbs found in herbal teas are safe for breastfeeding mothers and some companies that make herbal preparations, such as Celestial Seasonings, label their products accurately so that consumers know exactly what they are getting. The accurate labeling of ingredients in herbal preparations also makes it possible for poison control centers to know what they are dealing with in the case of overdose. So, reliable brands of herbal tea like Celestial Seasonings should be safe, as long as the ingredients included are okay for breastfeeding mothers to ingest.

Breastfeeding mothers should stick with herbal teas that are not full of potent pharmacologic preparations. Orange cinnamon, lemon lift, and raspberry teas are good choices. Another fine choice is tea made from rose hips (the berry-like formation left after the rose pedals drop away), which contains a lot of Vitamin C.

Some herbs that are found in teas should be avoided. There is a native plant in Mexico, for example, that has a vanilla-like flavor and tinctures of the root of this plant are sold as imitation vanilla. Small amounts of this preparation used in cooking are safe, but drinking large amounts of tea with this ingredient could cause serious bleeding over time, because of the native anticoagulant in this plant. There are other teas native to the Southwest that contain compounds called pyrrolizide alkaloids known to cause occlusion of the veins, especially the liver, and finally liver failure. A cup of tea now and again is reasonably safe, but drinking several cups on a daily basis could lead to serious cardiovascular and liver disease. Comfrey (Symphytum officinale), an herb used to heal wounds topically or to heal ulcers internally contains alkaloid substances associated with occlusion of the veins. Comfrey is often confused with the plants nightshade and foxglove by inexperienced herbalists, and it has been banned in Canada because of its dangerous side effects.

Be Cautious About Taking Herbal Dietary Supplements While Nursing

Some herbs are touted as excellent dietary supplements, particularly because they contain microminerals such as selenium and zinc. While most herbs are safe in small amounts, there is no quality control mechanism to guarantee the dosage or exact ingredients of herbal dietary supplements. Because a variety of herbs - including pharmacologically active herbs such as ginkgo, ginseng, kava, and valerian - often are added to dietary supplements, taking them can be risky for breastfeeding mothers. The danger associated with these herbs is that they can cause side effects if ingested in large quantities over time. For example, large doses of ginseng can give you a "buzz", and when it is discontinued there is a significant withdrawal - similar to that of caffeine withdrawal. This is often called "ginseng syndrome." A good rule of thumb is that a nursing mother should not consume a dietary supplement if it is unlabeled, if ingredients are not measured accurately, or if it contains any pharmologically active substances.

The Effect of Herbs on Milk Production is Questionable

Breastfeeding mothers are often interested in increasing their milk supply, particularly when mother and baby have been separated because of illness and the baby has been unable to nurse at the breast. The herbal literature suggests that some herbs increase milk production. Number one on this list is fenugreek (Trigorvella foenum-graecuml), an herb that can cause low blood sugar (hypoglycemia) and has been tried in the management of diabetes, albeit unsuccessfully. Diabetics must monitor their blood sugar and measure the dosage of medication to manage their illness very carefully, making it very difficult to control the disease with natural substances.

Fenugreek probably has little effect on milk supply until a mother takes large amounts of (about three capsules, three times per day, but this varies from pill-to-pill) and her milk and urine begin to smell like maple syrup, though no clinical trials have been conducted to prove or disprove this relationship. When a mother takes large quantities of fenugreek, the baby begins to smell like maple syrup too, and some babies have been misdiagnosed as having "maple syrup urine disease," a serious metabolic disorder. Another danger associated with fenugreek is that the herb is related to peanuts, the food most likely to cause an allergy. The possibility of an allergic reaction in a baby is quite high, and many cases of colic, stomach upset, and diarrhea have been reported among babies whose mothers take fenugreek.

My own experience counseling women to use fenugreek to enhance milk production has been mixed. Many mothers at our lactation center report that fenugreek had no effect on their milk supply, while others are quite laudatory about its effect on the amount of milk they produce.

Another popular herb to enhance milk production is Blessed Thistle, an herb first described by the monks in the Middle Ages as a cure for smallpox. Today, it is most commonly used in herbal medicine as a contraceptive and to treat infections or fever. There is no scientific evidence to support that Blessed Thistle stimulates milk production, nor are there studies that report a safe dosage of this herb. In modest amounts, however, it is probably safe for breastfeeding mothers.

Fennel (Foeniculum vulgare), a licorice flavored herb that has been used since the Middle Ages, also has gained a reputation for promoting lactation. Although there is no scientific evidence that fennel increases milk production, it is safe for breastfeeding women when used in small amounts. Fennel is commonly used to season fish and vegetable dishes. Herbalists still recommend a tea made from crushed fennel seeds (fruits) as a remedy for stomachache and cramps, and some people use fennel to relieve colic and gas. Historically, fennel was thought to have appetite-suppressing effects, though this has not been proven.

Although small amounts of fennel are safe when the seeds or fruits from the fennel plant are used, oil from the fennel plant should be avoided. This volatile oil is toxic and can cause seizures and respiratory problems in doses as small as 1 to 5 milliliters (less than 1 teaspoon).

Other Herbal Therapies Should Be Used Only After Checking With Your Physician

Echinacea (Echinacea angustifolia), an herb thought to boost the immune system, has become popular to treat cold symptoms. Evidence of the effectiveness of Echinacea has been mixed. One recent clinical trial found that Echinacea lessened symptoms of the common cold compared to a placebo, when it was taken at the onset of symptoms. Another clinical trial found no benefit associated with taking Echinacea on a regular basis to avoid such infections, however. Although its effectiveness is questionable, these studies suggest that Echinacea is probably safe when taken for short periods of time, except in individuals who are allergic to ragweed, chrysanthemums and related plants. The Echinacea plant itself is a commonly recognized, purple cone flower that is a member of the daisy family.

St. John's Wort (hypericum perforatum), a plant once considered to have supernatural powers, is probably the best-known therapeutic herb used today. The ancient Greeks believed that the fragrance of St. John's Wort would drive evil spirits away, and the ancient Christians considered it a symbol of St. John the Baptist because its flowers bloom on June 24, the day designated as St. John's Day.

St. John's Wort has been used as a treatment for sadness and depression for many years. Today, it is widely used as an antidepressant in Europe, where it has been approved for sale as a medicine. A few small clinical trials have found that St. John's Wort has a therapeutic effect not unlike other pharmacologic antidepressants. Like Prozac and Zoloft, for example, it is a serotonin reuptake inhibitor, which means that it blocks the utilization of the brain chemical serotonin.

Breastfeeding mothers should not take St. John's Wort without consulting their physician first. Although it is a natural substance, St. John's Wort works like many other antidepressants and can be dangerous if not used appropriately. It can reduce the effect of some prescription drugs, for example, and should not be taken with other antidepressants. Because St. John's Wort can be purchased without a prescription, people may use it to treat self-diagnosed symptoms of depression independently, and they may not seek necessary medical advice.

For some individuals, St. John's Wort can have other very unpleasant side effects. The combination of St. John's Wort and ragweed exposure can cause a very serious allergic reaction in individuals who have allergies, especially asthma. The herb also can cause skin burns in light-skinned people because is contains hypersen, a photosensitizing substance that reacts with light. Even though a prescription is not required, it is wise to talk with your physician before taking St. John's Wort regularly.

Recommendations

Avoid the pharmacologically active herbal teas. Drink any herbal teas only in moderation.
Limit intake of any herbal preparation that combines several active ingredients.
Always check the label. Even vitamins and simple echinacea may contain herbs that should not be used by breastfeeding mothers, such as ginkgo or ginseng.
Use only reliable brands that have ingredients and concentrations clearly marked on the label, as well as the expiration date and the name of the manufacturer and distributor.
Be sure to check with your physician before taking any natural remedy, since it could interact with other medications you take or need.

Additional resources for information about the use of herbs:

Foster S, Tyler VE. Tyler's Honest Herbal: A sensible guide to the Use of Herbs and Related Remedies (4th edition). Haworth Press, Inc., New York, 1999.

Reader's Digest. Magic and Medicine of Plants. The Readers Digest Association Inc., 1996.