Slippery elm
Red elm, moose elm, Indian elm, sweet elm; Ojibwe anib; Ulmus rubra, in the older books Ulmus fulva Michx.
- Known today as
- Ulmus rubra, a medium-sized deciduous elm native, LiverTox writes, to the eastern and central United States and Canada, “called slippery because of the slippery texture of the inner bark when it is chewed or mixed with water.” The inner bark is the drug. Grieve describes it in commerce as long, thin, tough, flexible strips that can be bent double without breaking, smelling of fenugreek, and records that, the wood having no commercial value, the tree was fully stripped and died. Its chief constituent is a mucilage, so abundant that a little of the powder makes a thick jelly with water.
- Kind
- Plant, in 1 older authority
- Constituents
- mucilage, tannins, calcium oxalate
- Earliest authority here
- Grieve, A Modern Herbal (1931) (A Modern Herbal, 1931)
- In other databases
- Plants of the World Online · GBIF · Wikidata
Caution. LiverTox records that it is designated “generally recognized as safe,” that there is no reliable data on its adverse effects, and that it has been linked to rare skin allergies; it has not been implicated in liver injury.
Slippery elm: what was it used for?
A demulcent for the throat and the gut, a food for invalids, and a poultice. Smith records in 1932 that the Pillager Ojibwe used the slippery inner bark “for sore throat, especially when the throat is apt to be dry.” Grieve calls it one of the most valuable remedies in herbal practice: made into a gruel it was a food for infants and invalids, “tolerated by the stomach when all other foods fail,” given in gastritis, colitis, and coughs; and the coarse powder made what herbalists thought one of the best poultices for wounds, boils, ulcers, and burns. LiverTox names its present uses as a lozenge for sore throat, a pill for an upset stomach, and a cream for rashes and wounds.
Slippery elm: what does modern science say?
No European monograph covers it, and it is not approved as therapy for any disease or condition. LiverTox, revised in 2024, explains its effects by the mucilage, which may soothe a sore or dry throat and coat irritated lining of the gullet and stomach, with tannins and resins that may add an astringent effect; but it notes that there have been no large clinical trials reporting on its adverse effects, and the searches of Europe PMC made for this entry found no trial of slippery elm alone.
Pharmacognosy & Toxicology
- Constituents
- mucilagethe principal constituent, in large cells in the bast; very like that of linseed
- tanninswith resins, which may add an astringent effect
- calcium oxalateas twin crystals
- Mechanism
- LiverTox explains its effects by the mucilage, which may soothe a sore or dry throat and coat irritated lining of the gullet and stomach.
- Standing
- There is no European monograph. Designated “generally recognized as safe” in the United States; official in the United States Pharmacopoeia in Grieve’s day.
- LiverTox: Clinical and Research Information on Drug-Induced Liver Injury, “SlipperyElm.” National Institute of Diabetes and Digestive and Kidney Diseases, updated 2024. NCBI Bookshelf. Read in full · the text read
- Grieve, M. A Modern Herbal, “Elm, Slippery.” As published on botanical.com. Read in full · the text read
Constituent names open the compound’s record at PubChem, and “ChEMBL” beside a name opens its record at ChEMBL, the European Bioinformatics Institute’s database of bioactive molecules. Where a mechanism line was checked against ChEMBL (ChEMBL 37, read 1 October 2026), the check is shown with the measured value and its source paper, or says plainly that nothing has been measured. Doses are as the references give them, for description only; this is not medical advice. Each source carries the result of its check against Crossref, PubMed, or the authority’s page: see Verification.
Slippery elm: what lore surrounds it?
Grieve reports the assertion that a pinch of the powder put into a hollow tooth stops the ache and delays decay, and warns that the powdered bark was often adulterated with damaged flour.
Slippery elm: what did the older authorities say?
- Grieve, A Modern Herbal (1931)
- “The Red Indians have long used this viscous inner bark to prepare a healing salve,” Grieve writes, and herbalists after them made it into poultices of every kind: with charcoal for old gangrenous wounds, with brewer’s yeast and new milk to hasten suppuration, with bran and hot vinegar for rheumatic and gouty joints. The moistened bark could be moulded into pessaries, teats, and suppositories, and it was said to keep fats from going rancid.
Sources
- Smith, H. H. (1932). Ethnobotany of the Ojibwe Indians, Slippery Elm. Bulletin of the Public Museum of the City of Milwaukee 4. Project Gutenberg, 49527. Read in part · the text read
- Grieve, M. A Modern Herbal, “Elm, Slippery.” As published on botanical.com. Read in full · the text read
- LiverTox: Clinical and Research Information on Drug-Induced Liver Injury, “SlipperyElm.” National Institute of Diabetes and Digestive and Kidney Diseases, updated 2024. NCBI Bookshelf. Read in full · the text read
Verification
- Checked
- October 1, 2026
- Passes
- Every sentence read against its sources, in the pass over the remaining 343 entries
- The Standing line checked against the authority it names (EMA, WHO, FDA, CITES, Commission E)
- Every dated or regulatory claim checked by category across the database
- Sources
- 3 cited: 2 read in full, 1 read in part.
- Corrections
- None were needed.
What was checked, how, and what was found is set out on the Verification page. A checked source is one whose record was found; it does not make the entry medical advice.
Club members can point at a technical term in this entry, such as a constituent, an action, or a word of Jung’s, to read its definition from the source. The Club.
Cite This Entry
Version 1 · first published October 17, 2026
- Chicago
“Slippery elm.” In Materia Medica, edited by B. C. P. Statema. Version 1. The Thinking Press, 2026–. Last modified October 17, 2026. https://thethinkingpress.org/materia-medica/slippery-elm.
- MLA
“Slippery elm.” Materia Medica, edited by B. C. P. Statema, version 1, The Thinking Press, 17 Oct. 2026, thethinkingpress.org/materia-medica/slippery-elm. Accessed 17 Oct. 2026.
- APA
Slippery elm. (2026, October 17). In B. C. P. Statema (Ed.), Materia medica (Version 1). The Thinking Press. Retrieved October 17, 2026, from https://thethinkingpress.org/materia-medica/slippery-elm
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See Also
Sharing mucilage, tannins
Polygonatum multiflorum · Cydonia oblonga · Viola odorata · Plantago ovata · Fragaria vesca · Prunella vulgaris · Galium odoratum · Sorbus aucuparia
Also in M. Grieve
Skullcap in M. Grieve · Sumac in M. Grieve · Witch hazel in M. Grieve · everything M. Grieve names →
Drawing on the same sources: Smith, Grieve
Ramps · Wild bergamot · Snapdragon · Soapwort · the bibliography →
Nearby in the alphabet
Snail (shelled and boiled, distilled, or eaten) · Silver · Silphium (probably a giant fennel (Ferula)) · The sickener (very fragile mushroom of woods, especially of beech)
Historical description, not medical advice.
