Napiers Slippery Elm Powder (Ulmus rubra)A herbal food supplement to support the gastrointestinal tract A herbal food supplement containing pure, sustainably sourced, powdered slippery elm inner bark. This is a nutritious food supplement traditionally included in the diets of invalids and the elderly. It is also a soothing supplement that may be enjoyed by those prone to issues with stomach acidity or irritable gut conditions. In 1898, a tablespoonful of the powder would be boiled in a pint