TONGKAT ALI: Eurycoma Longifolia (commonly called tongkat ali or pasak bumi) is a flowering plant in the family Simaroubaceae, native to Indonesia, Malaysia, and, to a lesser extent, Thailand, Vietnam, and Laos. It is also known under the names penawar pahit, penawar bias, bedara merah, bedara putih, lempedu pahit, payong ali, tongkat baginda, muntah bumi, petala bumi (all the above Malay); bidara laut (Indonesian); babi kurus (Javanese); cay ba binh (Vietnamese) and tho nan (Laotian). Many of the common names refer to the plant's medicinal use and extreme bitterness. "Penawar pahit" translates simply as "bitter charm" or "bitter medicine". Older literature, such as a 1953 article in the Journal of Ecology, may cite only "penawar pahit" as the plant's common Malay name.
An Italian study on Eurycoma longifolia noted improved sexual performance in lab animals and concluded that the "effect could be mainly ascribed to increased testosterone levels. After scientists investigating Eurycoma Longifolia's effect on sexual parameters had established that sexualizing effects went hand-in-hand with increased testosterone tone, researchers in the field of sports medicine started to look into the anabolic potential of the plant.