Nature's Way Slippery Elm Bark - A traditional, natural remedy used for centuries both topically and internally, Slippery Elm's main application has been to soothe and relieve irritated, inflamed tissue and mucous membranes in the stomach, bowels and urinary tract. Also helpful in relieving inflamed lungs, sore throats and irritated kidneys. Slippery Elm should not be taken when pregnant. Nature's Way Slippery Elm is derived from wild trees through a conscientious stripping process that does not harm the tree.