The bark of the slippery elm has a long history of use in Native American medicine, both topically and internally. The Memorial Sloan Kettering Cancer Center (MSKCC) notes that no human or animal studies have ever been conducted on this herb, but a review of its components indicates a low risk of toxicity or negative side effects.
Sore Throat and Cough
Slippery elm contains mucilage, a substance that offers soothing relief by forming a thin film that eases pain, inflammation and irritation. It helps repress the cough reflex, notes WholeHealthMD.com, a website created and maintained by doctors and other integrative medicine experts. This treatment might also help bronchitis, but the MSKCC does not recommend using it for this more serious condition.
The benefits of mucilage extend to gastrointestinal disorders by providing a protective film over the digestive tract, making it useful for upset stomach, heartburn and other digestive problems. Slippery elm stimulates nerve endings that increase mucous production in the gastrointestinal tract, which offers protection against excessive acid production. Slippery elm contains tannins, which control irritation and fluid movement, making it beneficial for diarrhea and for irritable bowel syndrome.
Inflammatory Bowel Diseases
The University of Maryland Medical Center (UMMC) indicates that slippery elm contains antioxidants that appear to ease the inflammation characteristic of Crohn's disease and ulcerative colitis, serious intestinal disorders that produce a number of unpleasant symptoms like bloody stools, diarrhea, pain and cramping.
Considerations for Use
The MSKCC notes that no side effects or negative interactions have ever been reported in any medical literature. The UMMC explains that the medical community believes you can safely use this herb when pregnant or breastfeeding, though no scientific evidence exists to confirm this. Children can probably safely use slippery elm at one third the adult dose. If you want to make a tea, try using 2 cups of boiling water for every 2 tbsp. of the powdered bark.
Because of the coating effects of the mucilage, this herb might interfere with the absorption of orally administered medications, herbs and other supplements. To avoid this potential negative effect, do not use slippery elm for two hours before or after taking medicine.