Tongkat Ali (Eurycoma longifolia Jack) also known as Malaysian Ginseng, has an ancient reputation as an aphrodisiac. The herb increases testosterone levels, and is also effective for women who need some quantity of testosterone too.
One also feels that energy has improved and there is a sense of well-being.
Laboratory studies have confirmed that its traditional use as an aphrodisiac is considerable and is not a placebo. Further research has also revealed anxiety relieving effects.
The raw extract from the root of Butea superba contains flavonoids and
flavonoid glycosides demonstrating benefits to sexual performance,
without the side effects that popular modern drugs have.
Many studies reveal a strong vasodilation effect, via the production of nitric oxide. Enzymatic tests have shown Butea superba to be a potent inhibitor of c-AMP Phosphodiesterase which reacts directly at the corpus cavernosum in the penis enhancing blood flow to the penis area leading to a
more frequent, longer lasting, stronger male sexual arousal, and stamina.

Clinical trial of Butea superba, in treatment of erectile dysfunction
Clinical trial of Butea superba, an alternative herbal treatment for erectile dysfunction
W. Cherdshewasart1, N. Nimsakul2
1Department of Biology, Faculty of Science, Chulalongkorn University, Phyathai Road, Bangkok 10330, Thailand
2Deja General Hospital, Sriayudhya Road, Bangkok 10600, Thailand
Asian J Androl 2003 Sep; 5: 243-246
Aim: To study the effect of Butea superba on erectile dysfunction (ED) in Thai males.
Methods: A 3-month randomized double-blind clinical trial was carried out in
volunteers with ED, aged 30 years ~ 70 years,
to evaluate the therapeutic effect of the Butea superba tubers on ED.
Results: There was a significant upgrading in 4 of the 5 descriptive evaluations
of the IIEF-5 questionnaire.
Estimation of the sexual record indicated that
82.4 % of the patients exhibited noticeable improvement.
Haematology and blood chemistry analysis revealed no apparent change.
Conclusion: The plant preparation appears to improve the erectile function in ED patients without apparent toxicity.
The Butea Superba (or Red Kwao Krua) contains high amount of phytoandrogens, which imitate male hormones, which may be attributable to rejuvenating effects such as regaining muscle and bone strength, agility, and impoving sexual desire.