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 also contains antioxidants that help relieve inflammatory bowel conditions. Slippery elm also causes reflux stimulation of nerve endings in the gastrointestinal tract leading to increased mucus secretion. The increased mucus production may protect the gastrointestinal tract against ulcers and excess acidity.

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, ulcerative colitis, and irritable bowel syndrom (IBS)
• Diarrhea
• Wounds, burns, boils, psoriasis, 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, and they darken 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

Give slippery elm to a child only under the supervision of a knowledgeable practitioner. Dosage is usually dependent on weight.

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, then steep for 3 - 5 minutes. Drink 3 times per day.
• Tincture: 5 mL 3 times per day. Note: Contains alcohol.
• Capsules: 400 - 500 mg 3 - 4 times daily for 4 - 8 weeks. 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, you should take herbs 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.

Scientists think slippery elm is safe in pregnancy and during breastfeeding, but no scientific studies have been done to confirm this. In fact, some herbalists believe that slippery elm can cause miscarriage. The outer bark of the elm tree may contain substances that could increase the risk of miscarriage, so sometimes pregnant women are advised to avoid slippery elm. Do not take any herbal supplements when pregnant or breastfeeding unless you're under the supervision of a physician.

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" section).

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