Nettle root comes from the stinging nettle plant. With a long tradition of medicinal use, stinging nettle was historically used to treat joint pain and help the body rid itself of excess water. Nettle root is more commonly used than the leaves and appears to have different medicinal properties. It can be consumed as an extract, tea, capsule, tincture, or applied topically. Medicinal uses include: to treat joint ailments, as a diuretic, astringent and to treat an enlarged prostate.