Slippery elm (Ulmus rubra) is a tree that is native to North America. Its inner bark feels slippery when chewed and may be effective for soothing sore throat.

Only the inner bark of slippery elm, not the whole bark, is used as medicine. The inner bark contains chemicals that can increase mucous secretion, which might be helpful for stomach and intestinal problems.

People use slippery elm for sore throat, constipation, stomach ulcers, skin disorders, and many other conditions, but there is no good scientific evidence to support these uses.

There is interest in using slippery elm for a number of purposes, but there isn’t enough reliable information to say whether it might be helpful.

When taken by mouth: Slippery elm is possibly safe for most people.

When applied to the skin: There isn’t enough reliable information to know if slippery elm is safe when applied to the skin. In some people, slippery elm can cause allergic reactions and skin irritation when applied to the skin.

Special precautions & warnings:

Pregnancy and breast-feeding: Folklore says that slippery elm bark can cause a miscarriage when it’s inserted into the cervix during pregnancy. Over the years, slippery elm got the reputation for causing an abortion even when taken by mouth. Although there’s no reliable information to confirm this claim, stay on the safe side and avoid slippery elm if you are pregnant or breast-feeding.

Moderate

Be cautious with this combination.

Medications taken by mouth (Oral drugs)

Slippery elm contains a type of soft fiber called mucilage. Mucilage can decrease how much medicine the body absorbs. Taking slippery elm at the same time you take medications by mouth can decrease the effectiveness of your medication. To prevent this interaction, take slippery elm at least one hour after medications you take by mouth.

There are no known interactions with herbs and supplements.

There are no known interactions with foods.

There isn’t enough reliable information to know what an appropriate dose of slippery elm might be. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult a healthcare professional before using.

Indian Elm, Moose Elm, Olmo Americano, Orme, Orme Gras, Orme Rouge, Orme Roux, Red Elm, Sweet Elm, Ulmus fulva, Ulmus rubra.

To learn more about how this article was written, please see the Natural Medicines Comprehensive Database methodology.

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