Tongkat ali is a herbal medication (Jamu) widely used in Malaysia as an aphrodisiac for men. In Indonesia, the same medication is known as pasak bumi.
Even though the herbal is largely unknown in the US and Europe, the pro-sexual effect of tongkat ali is actually well documented in Western science. Anybody can check this for himself at the Medline database.
To search for scientific information, one has to use the plants scientific, Latin name, eurycoma longifolia. The plant is also a proven therapeutic and preventive medication against malaria, so in order to focus the search on the pro-sexual properties, one should use the additional search term "sexual".
Tongkat ali improves sex by raising testosterone levels, or, more specifically, the levels of free testosterone. A large proportion of the testosterone that circulates in the human, primarily male, body is bound by a protein, SHBG (sex hormone binding globulin).
Testosterone that is bound to SHBG is rendered ineffective. Only free testosterone exerts the effects that are attributed to the hormone: one androgenic (masculinizing and sexualizing, both physiologically and mentally, and thus enhancing libido) and one anabolic (building tissue, mainly muscle).
