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. It was also taken orally to relieve coughs, sore throats, diarrhea, and stomach problems.

Slippery elm contains mucilage, a substance that becomes a slick gel when mixed with water. It coats and soothes the mouth, throat, stomach, and intestines; it may also contain antioxidants that can help relieve inflammatory bowel conditions.

There has been little scientific research on slippery elm, but it is often suggested for the following conditions:

• Sore throat
• Cough
• Gastroesophogeal reflux disease (GERD)
• Crohn's disease and ulcerative colitis
• Diarrhea
• Wounds, burns, boils, and other skin conditions (external)

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 inner bark is dried and powdered, and used for medicinal purposes.

Available forms of slippery elm include the following:

• Tablets and capsules
• Lozenges
• Finely powdered bark for making teas or extracts
• Coarsely powdered bark for poultices

Pediatric

Although there are no scientific studies examining the use of slippery elm in children, it is generally considered to be safe. Adjust the recommended adult dose to account for a child's weight. Most herbal dosages for adults are calculated on the basis of a 150 lb (70 kg) adult. So if the child weighs 50 lb (20 - 25 kg), the appropriate dose of slippery elm would be 1/3 of the adult dose.

Adult

The following are recommended adult doses for slippery elm:

• Tea: Pour 2 cups boiling water over 4 g (roughly 2 tablespoons) of powdered bark and then steep for 3 - 5 minutes. Drink three times per day.
• Tincture: 5 mL three times per day. Note: Contains alcohol.
• Capsules: 800 - 1,000 mg three times daily. Take with a full glass of water.
• Lozenges: follow dosing instructions on label.
• External application: Mix coarse powdered bark with boiling water to make a poultice; cool and apply to affected area. Never apply slippery elm to an open wound.

The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, can trigger side effects and can interact with other herbs, supplements, or medications. For these reasons, herbs should be taken with care, under the supervision of a health care provider.

Slippery elm has no serious side effects. Because it coats the digestive tract, it may slow down the absorption of other drugs or herbs. You should take slippery elm 2 hours before or after other herbs or medications you may be taking.

Slippery elm is thought to be safe in pregnancy and during breastfeeding, but no scientific studies have been done to confirm this. The outer bark of the elm tree, however, may contain substances that could increase the risk of miscarriage, so sometimes pregnant women are advised to avoid slippery elm.

There are no scientific reports of slippery elm interacting with any other medications, although it may slow down the absorption of other drugs or herbs (see "Precautions").

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.

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

Kemper KJ. Slipper elm (Ulmus rubra or U. fulva). The Longwood Herbal Task Force and The Center for Holistic Pediatric Education and Research. Revised Sept. 29, 1999. Online at http://longwoodherbal.org/slipperyelm/slipperyelm.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.

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.