Slippery elm (Ulmus fulva) has been used as an herbal remedy in North America for centuries. Native Americans used slippery elm in healing salves for wounds, boils, ulcers, burns, and skin inflammation. Antiseptic poultices made from the mucilage or gummy secretion from the bark were applied to infected wounds. In particular, the Cherokee used Slippery elm for coughs, skin conditions, and as an eye wash.

Slippery elm is also one of four herbs included in a popular therapy called essiac that is promoted for cancer treatment. This remedy was developed by a nurse in Canada in the early 1930's. Later, the formula was expanded from its original inclusion of slippery elm, burdock root, sheep sorrel and Turkish rhubarb to also include red clover, water cress, blessed thistle, and kelp. Today, reports state that there are over 40 variations of these herbal combination remedies on the market, without scientific proof that any of them work.

The conditions for which slippery elm has received recognition from the U.S. Food and Drug Administration (FDA) as a safe and effective option include sore throat (pharyngitis) and respiratory symptoms, such as cough. Herbalists also recommend it for external use to treat wounds, cuts, and certain skin conditions, including diaper rash.

Because of its growing popularity, there has been an increasing demand for slippery elm bark. However, since the wood of the slippery elm tree has no commercial value, the trees are left to die after their bark has been harvested. This has led the National Center for the Preservation of Medicinal Herbs to launch an effort aimed at promoting sustainable cultivation of slippery elm.

Slippery elm is also considered a wholesome nutritional food, similar in texture to oatmeal and can be prepared as a porridge. Consumed three times per day, unsweetened "elm food" may be a good source of nutrients. Because it is gentle and easily digested, it is well tolerated by people with gastritis and other forms of intestinal problems.

Slippery elm is a medium-sized tree native to North America. It can reach well over 50 feet in height and is topped by spreading branches that form an open crown. The red-brown or orange branches grow downward, and the stalkless flowers are arranged in dense clusters. The plant's leaves are long and green, darkening in color during the fall. The bark has deep fissures, a gummy texture, and a slight but distinct odor.

The slippery elm's inner bark is used for medicinal purposes.

While there has been little scientific research on slippery elm, it has a long history of use based on clinical experience. Some of the conditions that seem to respond to slippery elm include:

• Sore throat
• Cough
• Mild respiratory ailments
• Gastritis, peptic ulcer, and other gastrointestinal conditions
• Diarrhea
• Wounds, burns, boils, and other skin conditions (external)
• Skin softener

Slippery elm has been used in Ayurvedic and Traditional Chinese Medicine for gastrointestinal symptoms including bloody diarrhea. This herb is thought to work for such intestinal problems because of its demulcent properties, which means that it coats and soothes the digestive tract. Recent laboratory research on slippery elm suggests that this traditional application may prove to have scientific merit in treating inflammatory bowel disease (namely, Crohn's disease and ulcerative colitis); the authors of this study propose that it is the antioxidant properties of slippery elm that would offer such protection. Conclusions regarding this preliminary information, however, will have to wait on studies of people.

Commercial preparations are made from 10-year-old inner bark sold in long flat pieces about two to three feet long, between 1/8 and 1/16 of an inch in thickness. Available forms of slippery elm include the following:

• Tablets and capsules
• Lozenges
• Finely powdered bark for drinks (infusions and decoctions and liquid extracts)
• Coarsely powdered bark for poultices

Pediatric

Adjust the recommended adult dose to account for the child's weight. Most herbal dosages for adults are calculated on the basis of a 150 lb (70 kg) adult. Therefore, if the child weighs 50 lb (20 to 25 kg), the appropriate dose of slippery elm for this child would be 1/3 of the adult dose.

Adult

The following are recommended adult doses for slippery elm:

• Decoction: prepare by simmering for an hour or longer one part powdered bark to eight parts water. This will make a mucilaginous drink that can be taken as often as needed, or added to juice or oatmeal.
• Infusion: prepare by pouring 2 cups boiling water over 4 grams (roughly 2 tablespoons) of powdered bark and then steeping for 3 to 5 minutes. Drink three times per day
• Capsules: two capsules (250 to 500 mg), three times daily
• Lozenges: follow dosing instructions on label
• External application: Mix coarse powdered bark with boiling water to make a poultice.

The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, contain active substances that can trigger side effects and interact with other herbs, supplements, or medications. For these reasons, herbs should be taken with care, under the supervision of a practitioner knowledgeable in the field of botanical medicine.

There are no known health hazards reported for slippery elm when it is properly administered in recommended therapeutic doses. However, taking slippery elm with oral medications may decrease the absorption of these medications; therefore, it may be a good idea to take slippery elm several hours before or after other herbs or medications you may be taking.

Based on use by and experience of herbal specialists, slippery elm is thought to be safe in pregnant and nursing women, but this has not been tested scientifically.

There are no reports in the scientific literature to suggest that slippery elm interacts with any conventional medications. As stated in Precautions, however, it is best to take slippery elm several hours before or after other herbs or medications because of possible interference with absorption.

Blakley T. Slippery elm: Comparative study of the effects of plant spacing on plant development and yield. Research Farm Proposal No. 6088. Collaborating Team, The National Center for the Preservation of Medicinal Herbs. Project Period 1998–2008. Accessed March 28, 2002 at: http://www.ncpmh.org/6088.html.

Bock S. Integrative medical treatment of inflammatory bowel disease. Int J Integr Med. 2000;2(5):21-29.

British Herbal Pharmacopoeia. 4th ed. Great Britain:Biddles Ltd, Guildford and King's Lynn; 1996.

Duke JA. Dr. Duke's Phytochemical and Ethnobotanical Databases. Agricultural Research Service (ARS), Phytochemical Database, USDA. Beltsville Agricultural Research Center, Beltsville, Maryland. Accessed March 28, 2002 at: http://www.ars-grin.gov/duke/.

Ernst E, Cassileth BR. How useful are unconventional cancer treatments? Eur J Cancer. 1999;35(11):1608-1613.

Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 2nd ed. Montvale, NJ: Medical Economics Company; 2000:697.

Hoffman D. Slippery elm. Accessed March 28, 2002 at: http://www.healthy.net/hwlibrarybooks/hoffman/materiamedica/slippery.htm.

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.

Kemper KJ. Slipper elm (Ulmus rubra or U. fulva). The Longwood Herbal Task Force and The Center for Holistic Pediatric Education and Research. Accessed April 29, 2002 at http://www.mcp.edu/herbal/default.htm.

Langmead L, Dawson C, Hawkins C, Banna N, Loo S, Rampton DS. Antioxidant effects of herbal therapies used by patients with inflammatory bowel disease: an in vitro study. Aliment Pharmacol Ther. 2002;16(2):197-205.

Low Dog T, Riley D, Carter T. Traditional and alternative therapies for breast cancer. Alt Therapies. 2001;7(3):36-47.

Newall C, Anderson L, Phillipson J. Herbal Medicines: A Guide for Health-care Professionals. London: Pharmaceutical Press; 1996:248.

Rotblatt M, Ziment I. Evidence-based Herbal Medicine. Philadelphia, Penn: Hanley & Belfus, Inc.;2202:337-338.

Tamayo C, Richardson MA, Diamond S, Skoda I. The chemistry and biological activity of herbs used in Flor-Essence herbal tonic and Essiac. Phytother Res. 2000;14(1):1-14.