Uncaria gambir is commonly known as catechu and gambier and is also called Er Cha in Chinese, Kachu, and Gambir in Malay. U. gambir is a member of the Rubiaceae family and is found in tropical regions, particularly in Indonesia and Malaysia. This plant has been known to have many medicinal properties; it is used to treat diarrhea and sore throat because all parts of U. gambir have astringent properties. In Malaysia and Indonesia, it is used as a medicine and for many other purposes, such as dyeing and tanning. Occasionally, it is used as a food additive. In Borneo, it is used in the treatment of sciatica and lumbago. This plant is rich in flavonoids such as catechins which are associated with health-protective and cancer-preventive properties.