The herbal supplement of Slippery Elm is the inner bark of the Slippery Elm tree. 

It is common to take a supplement of slippery elm for coughs, sore throat, colic, diarrhea, constipation, hemorrhoids, irritable bowel syndrome (IBS), bladder and urinary tract infections, syphilis, herpes, and for expelling tapeworms. It is also used for protecting against stomach and duodenal ulcers, for colitis, diverticulitis, GI inflammation, and too much stomach acid. 

Slippery elm contains properties that can help soothe sore throats and can also cause mucous secretion which might be helpful for digestive and intestinal problems.