I’ve been told that an herbal remedy should not be taken over long periods because it reduces its effectiveness and that it should be taken for several weeks, then not taken for a week or two. Does this apply to all herbs? In particular, I’m wondering about wild yam, vitex and black cohosh for easing PMS and menopausal problems.
—T. B. Littleton, CO
Gladstar responds: If one observes nature, our greatest teacher, one sees that everything is cyclic. In accordance with this cyclic pattern, herbs, even those that have no harmful side effects, are best taken in cycles. Tonic herbs are generally taken in a rotational cycle; these herbs are classified as “superior medicine” by the Chinese because they are safe, gentle and meant to be used over a prolonged period. The cycle often suggested for tonics is five days on and two days off. This cycle can be repeated as long as necessary because there are no side effects or contraindications for long-term use.
Some herbs, especially those with specific medicinal actions or herbs rich in alkaloids, do have contraindications and may have side effects if used for prolonged periods of time. One should definitely observe a rotating cycle followed by a rest period to avoid any harmful side effects.
Other herbs such as echinacea (Echinacea spp.) seem to lose their effectiveness if used for prolonged periods. Echinacea may still stimulate the immune system, but will do so with less pizzazz. Studies show that it maximizes after roughly five days, so the suggested cycle with echinacea is five days on, two days off, repeating the cycle as needed. With the use of the herbs you mentioned, a five-day-on, two-day-off cycle for four to six months would be appropriate.
Stansbury responds: Herbs generally do not lose their effectiveness over time. It’s more likely that they will become irritating or simply unnecessary when taken too frequently, for too long a duration, and at too high a dosage. Extensive herbal knowledge and refined prescribing are the keys to success.
When well indicated and selected, many herbs should be taken daily for many months for best effects. Examples of this are Asian ginseng (Panax ginseng) to improve vitality, ginkgo (Ginkgo biloba) to improve memory, and milk thistle (Silybum marianum) to support liver function.
Herbs that have greater toxic or irritating potential are used more short term. For example, uva ursi (Arctostaphylos uva-ursi) is taken for ten days for a bladder infection, cascara sagrada (Rhamnus purshiana) is used one time only for sluggish bowel function, and goldenseal (Hydrastis canadensis) is used short term for sore throats.
The herbs you mention for regulating hormones are used in a fairly long-term way, reducing the dosage over time so that the effects may be maintained with a lower dose. The herbs may be tapered off or replaced with other treatments as the menopausal transition is completed and symptoms subside. When intending to prescribe an herb for six months or many years, many herbalists and physicians will recommend taking a day or two off each week to provide a break from chronic usage.
Rosemary Gladstar, author of Herbal Healing for Women (Simon & Schuster, 1993) and several other books on herbalism, runs Sage Mountain Retreat Center and Native Plant Preserve in East Barre, Vermont. Her experience includes more than twenty years in the herbal community as a healer, teacher, visionary and organizer of herbal events.
Jill Stansbury has been a naturopathic physician for more than ten years, with a private practice in Battleground, Washington. She is the chair of the Botanical Medicine Department at the National College of Naturopathic Medicine in Portland, Oregon, and the author of many books, including Herbs for Health and Healing (Publication International, 1997).
The information offered in “Q & A” is not intended to be a substitute for advice from your health-care provider.