Slippery elm (Ulmus rubra Muhlor Ulmus fulva Michx)
Natural Standard Bottom Line Monograph, Copyright © 2013 (www.naturalstandard.com). Commercial distribution prohibited. This monograph is intended for informational purposes only, and should not be interpreted as specific medical advice. You should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.
While some complementary and alternative techniques have been studied scientifically, high-quality data regarding safety, effectiveness, and mechanism of action are limited or controversial for most therapies. Whenever possible, it is recommended that practitioners be licensed by a recognized professional organization that adheres to clearly published standards. In addition, before starting a new technique or engaging a practitioner, it is recommended that patients speak with their primary healthcare provider(s). Potential benefits, risks (including financial costs), and alternatives should be carefully considered. The below monograph is designed to provide historical background and an overview of clinically-oriented research, and neither advocates for or against the use of a particular therapy.
Indian elm, moose elm, red elm, rock elm, slippery elm, sweet elm, Ulmaceae (family), Ulmi rubrae cortex, Ulmus fulva Michaux, Ulmus rubra, winged elm.
The slippery elm is native to eastern Canada and the eastern and central United States where it is found mostly in the Appalachian Mountains. Its name refers to the slippery consistency the inner bark assumes when it is chewed or mixed with water. Slippery elm inner bark has been used historically as a demulcent, emollient, nutritive, astringent, anti-tussive, and vulnerary. It is included as one of four primary ingredients in the herbal cancer remedy, Essiac®, and in a number of Essiac-like products such as Flor-Essence®.
There is a lack of scientific studies evaluating the common uses of this herb, but due to its high mucilage content, slippery elm bark may be a safe herbal remedy to treat irritations of the skin and mucus membranes.
Although allergic reactions after contact have been reported, there is no known toxicity with typical dosing when products made only from the inner bark are used. Inner bark of slippery elm should not be confused with the whole bark, which may be associated with significant risk of adverse effects. Bark of Californian slippery elm (Fremontia Californica) is often used similarly medicinally, but it is not botanically related.
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
Slippery elm is found as a common ingredient in a purported herbal anticancer product called Essiac® and a number of Essiac-like products. These products contain other herbs such as rhubarb, sorrel, and burdock root. Currently, there is not enough evidence to recommend for or against the use of this herbal mixture as a therapy for any type of cancer.
Traditionally, slippery elm has been used to treat diarrhea. While theoretically the tannins found in the herb may decrease water content of stool, and mucilage may act as a soothing agent to inflamed mucous membranes, there is no reliable scientific evidence to support this indication. Systematic research is necessary in this area before a clear conclusion can be drawn.
Slippery elm is traditionally used to treat inflammatory conditions of the digestive tract such as gastritis, peptic ulcer disease, or enteritis. It may be taken alone or in combination with other herbs. Additional study is needed in this area before a clear conclusion can be drawn.
Slippery elm is commonly used to treat sore throats, most typically taken as a lozenge. Supporting evidence is largely based on traditional evidence and the fact that the mucilages contained in the herb appear to possess soothing properties. Additional study is needed in this area before a strong recommendation can be drawn.
*Key to grades:A: Strong scientific evidence for this use; B: Good scientific evidence for this use; C: Unclear scientific evidence for this use; D: Fair scientific evidence against this use (it may not work); F: Strong scientific evidence against this use (it likely does not work).
The below uses are based on tradition or scientific theories. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious and should be evaluated by a qualified health care professional.
Abscesses, abortifacient, abrasions, acidity, anal fissures, antihelminthic (expels worms), antioxidant, boils, bronchitis, burns, carbuncles, colitis, cold sores, congestion, constipation, cough, cystitis, demulcent, diuretic, diverticulitis, dysentery, emollient, eruptions, esophageal reflex, expectorant, gout, gynecological disorders, heart burn, hemorrhoids, herpes, immunomodulation, inflammation, laxative, lung problems, milk tolerance, pleurisy, psoriasis, rheumatism, swollen glands, synovitis, syphilis, toothache, typhoid fever, ulcerative colitis, vaginitis, varicose ulcers, wounds.
The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.
Adults (18 years and older)
There is no proven effective dose for slippery elm in adults. Slippery elm could theoretically slow down or decrease absorption of other oral medications due to hydrocolloidal fibers, although there is a lack of actual interactions reported. Teas, decoctions, liquid extracts, powdered inner bark preparations, and capsules/tablets are all commercially available.
Slippery elm bark 400-500-milligram tablets or capsules taken three or four times daily have been studied, although strengths may vary due to lack of standardization. Lower doses of 200-milligram capsules twice or three times per day have been used for bronchitis.
Slippery elm has been applied on the skin for wound care and inflammation. Typically, the coarse powdered inner bark is mixed with boiling water to make a paste. Various concentrations and application schedules have been used.
Children (younger than 18 years)
Traditionally, it has been accepted that slippery elm can be used safely in children complaining of stomach upset and diarrhea. However, there are no safety studies conducted in this area, and therefore use in children should only be under the strict supervision of a licensed healthcare professional.
The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.
Known allergy or hypersensitivity such as hives (urticaria) has been reported with slippery elm; some persons may have contact sensitivity to elm tree pollen (or sensitivity when breathing it in), but the frequency of allergic reactions to medicinal use of elm bark products is extremely rare.
Side Effects and Warnings
Contact dermatitis and urticaria have been reported after exposure to slippery elm or an oleoresin contained in the slippery elm bark. Based on historical accounts, whole bark of slippery elm (but not inner bark) may possess abortifacient properties.
Pregnancy and Breastfeeding
Avoid during pregnancy due to the risk of contamination with slippery elm whole bark, which may increase the risk of miscarriage.
Most herbs and supplements have not been thoroughly tested for interactions with other herbs, supplements, drugs, or foods. The interactions listed below are based on reports in scientific publications, laboratory experiments, or traditional use. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy.
Interactions with Drugs
Slippery elm could theoretically slow down or decrease the absorption of other oral medications due to hydrocolloidal fibers, although there is a lack of actual interactions reported. Slippery elm contains tannins, which could theoretically decrease the absorption of nitrogen-containing substances such as alkaloids, although there is a lack of actual interactions reported.
Interactions with Herbs and Supplements
Slippery elm could theoretically slow down or decrease the absorption of other herbs or supplements taken by mouth due to hydrocolloidal fibers, although there is a lack of actual interactions reported. Slippery elm contains tannins, which could theoretically decrease the absorption of nitrogen-containing substances such as alkaloids, although there is a lack of actual interactions have been reported.
This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).
Natural Standard developed the above evidence-based information based on a thorough systematic review of the available scientific articles. For comprehensive information about alternative and complementary therapies on the professional level, go to www.naturalstandard.com. Selected references are listed below.
Czarnecki D, Nixon R, Bekhor P, et al. Delayed prolonged contact urticaria from the elm tree. Contact Dermatitis 1993;28:196-197. View Abstract
DeHaan RL. Home remedies for pets. J Am Holistic Veterinary Med Assoc 1994;12:26.
Ernst E, Cassileth BR. How useful are unconventional cancer treatments? Eur J Cancer 1999;35(11):1608-1613. View Abstract
Gallagher R. Use of herbal preparations for intractable cough. J Pain Symptom Manage 1997;14(1):1-2. View Abstract
Kaegi E. Unconventional therapies for cancer: 1. Essiac. The Task Force on Alternative Therapies of the Canadian Breast Cancer Research Initiative. CMAJ 1998;158(7):897-902. View Abstract
Karn H, Moore MJ. The use of the herbal remedy ESSIAC in an outpatient cancer population. Proc Annu Meet Am Soc Clin Oncol 1997;16:A245.
Kato A, Ando K, Tamura G, et al. Effects of some fatty acid esters on the viability and transplantability of Ehrlich ascites tumor cells. Cancer Res 1971;31(5):501-504. View Abstract
Locock RA. Essiac. Can Pharm J 1997;130:18-20.
Luo W, Ang CY, Schmitt TC, et al. Determination of salicin and related compounds in botanical dietary supplements by liquid chromatography with fluorescence detection. J AOAC Int 1998;81(4):757-762. View Abstract
Tamayo C, Richardson MA, Diamond S, et al. The chemistry and biological activity of herbs used in Flor-Essence herbal tonic and Essiac. Phytother Res 2000;14(1):1-14. View Abstract
Copyright © 2013 Natural Standard (www.naturalstandard.com)
The information in this monograph is intended for informational purposes only, and is meant to help users better understand health concerns. Information is based on review of scientific research data, historical practice patterns, and clinical experience. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions.
March 22, 2017