Senna Leaf is commonly known as senna or Alexandrian senna, and its scientific name is Cassia angustifolia. It is a herb. The active components sennoside in senna leaf extract are anthraquinone derivatives and their glucosides, referred to as senna glycosides or sennosides. Senna is an FDA-approved over-the-counter (OTC) laxative. A prescription is not required to purchase senna. The two original kinds of senna (Cassia senna and Cassia angustifolia) used to make remedies are now mass-cultivated for medicinal purposes â?? primarily for their laxative properties. Senna is often taken as a tea, capsule, tablet or liquid extract. Senna has been used since the 9th century by Arabian physicians as a laxative and has been known as the "cleansing herb." "Only the leaves and the pods of the herb are therapeutically useful," states Herbs 2000.