I've heard some stuff about eurycoma longifolia. Its been studied as an aphrodisiac by one Chinese scientist. The only studies that exist that have any relevance to increase in hormones are by him. There is very little research about it, and none showing it can boost testosterone. Biotest and some others are now working on their own formula with this stuff in it.
Evaluation of the potency activity of aphrodisiac in Eurycoma longifolia Jack.
Ang HH, Ikeda S, Gan EK.
School of Pharmaceutical Sciences, University Science Malaysia, Minden, 11800, Penang, Malaysia.
[email protected]
The butanol, methanol, water and chloroform extracts of the roots of Eurycoma longifolia Jack were studied using various tests of potency of treated male rats. The results showed that E. longifolia produced a dose-dependent, recurrent and significant increase in the episodes of penile reflexes as evidenced by increases in quick flips, long flips and erections of the treated male rats during the 30 min observation period. These results provide further evidence that E. longifolia increases the aphrodisiac potency activity in treated animals. Copyright 2001 John Wiley & Sons, Ltd.
Effects of Eurycoma longifolia Jack (Tongkat Ali) on the initiation of sexual performance of inexperienced castrated male rats.
Ang HH, Cheang HS, Yusof AP.
School of Pharmaceutical Sciences, University Science Malaysia, Penang, Malaysia.
We studied the effects of Eurycoma longifolia Jack, commonly known as Tongkat Ali in Malaysia, on the initiation of sexual performance and the weights of sexual accessories in inexperienced castrated male rats. The doses of 200, 400 and 800 mg/kg body weight, which were extracted from E. longifolia Jack, were orally administered to the rats twice daily for 10 days prior to the tests and continued throughout the test period. Testosterone was used as a positive control after injecting 15 mg/kg daily subcutaneously for 32 days. Results showed that E. longifolia Jack produced a dose-dependent increase in sexual performance of the treated animals, but the E. longifolia Jack groups showed lower sexual performance in mounting, intromission and ejaculation than the testosterone group. Further results also showed that E. longifolia Jack promoted the growth of both ventral prostate and seminal vesicles as compared with the control, but the growth of sexual accessories at 800 mg/kg of butanol, methanol, water and chloroform fractions of E. longifolia Jack was less than that of testosterone treated group. The present study therefore gives further evidence of the folkuse of E. longifolia as an aphrodisiac.