Rhubarb, aka Rheum Palmatum, is used primarily for digestive complaints including constipation, diarrhea, heartburn, stomach pain, gastrointestinal (GI) bleeding, and preparation for certain GI diagnostic procedures. Some people use Rhubarb so they have to strain less during bowel movements; this reduces pain from hemorrhoids or anal fissures. Rhubarb is sometimes applied to the skin to treat cold sores. Rhubarb is a purgative and is most often used in herbal formulas for its strong laxative effects in constipation and colon cleansing formulas. It's most famously used as an ingredient in the classic Essiac cancer formula. The use of Rhubarb was recorded in the earliest Chinese herbal texts. Chinese physicians today use Rhubarb root teas to treat stubborn infections of the skin caused by staph infections. A powder of Rhubarb root and licorice can be made into a plaster to treat boils and furuncles.