LongJack testosterone erectile dysfunction, impotence tongkat aphrodisiac, erection
January 6 2017

Tongkat Ali (Eurycoma longifolia jack, also promoted as Longjack) is a small tree found in the jungles throughout Malaysia and Southeat Asia. It is commonly known as tongkat ali in Malaysia and Singapore, Piak or Tung Saw in Thailand, and Pasak Bumi in Indonesia. Tongkat Ali is used as a tonic and as a natural aphrodisiac herb.

Longjack, testosterone, and erectile dysfunction
Q. Is longjack herb effective for erectile dysfunction?
A. Yes, after a few days of use. There are other potent aphrodisiac herbs that work well for sexual enhancement and impotence, such as tribulus and back to yohimbe bark, although longjack supplement is quite effective as an Erection Enhancing herb.

Does Longjack increase testosterone levels?
A. Research in this area has been inconsistent with some studies showing testosterone release whereas others have not.

Bodybuilding, muscl growth, workouts in gym
We are not convinced that Longjack is an effective product for bodybuilding or building muscles.

What the Research says about Longjack:
Aphrodisiac, erectile dysfunction, impotence
Over the past few years, there have been quite a number of studies that have shown longjack to have sex-boosting properties. The effects of longjack were studied on the libido of male rats after dosing them with up to 800 mg per kilogram of body weight twice daily for 10 days. Results showed that longjack produced a dose-dependent increase in mounting frequency, that is, the number of times the male rats tried to mount the female rats increased as the dose given to the rats increased. In addition, the rats displayed more frequent and vigorous licking and anogenital sniffing towards the receptive females. Furthermore, the rats dosed with longjackspent more time grooming their genitals compared to the rats who were not given the plant. Genital grooming may be interpreted as masturbation. The researchers noticed another interesting finding: while the rats who had not received the plant showed normal behavior within the cage such as exploration and climbing the cage wall, the rats given longjack stayed around the females instead of exploring the cage. Longjack also increased the frequency of the rats’ erections.


Eurycoma longifolia Jack enhances sexual motivation in middle-aged male mice.
Ang HH, Lee KL, Kiyoshi M.
School of Pharmaceutical Sciences, University Science Malaysia, Minden, Penang, Malaysia.
J Basic Clin Physiol Pharmacol. 2003.
Longjack  was investigated for sexual motivation activity in adult, middle-aged male mice and in retired breeders, using the modified open field and the modified runway choice methods. Each mouse received 500 mg/kg of one of 4 fractions of Longjack  , viz. chloroform, methanol, butanol, and water, whereas the mice in the control and yohimbine groups received 3 ml/kg of normal saline and 30 mg/kg of yohimbine daily respectively for 10 d. The results show a transient increase in the percentage of male mice responding to the right choice after chronic consumption of the fractions with 50 percent of the adult middle-aged male mice treated with Longjack  and yohimbine scoring the right choice after 8 and 5 days post-treatment respectively. In conclusion, this study has shown that Longjack  continues to enhance sexual motivation in adult, middle-aged male mice and in retired breeders.

Longjack mechanism of action, how does it work
Very little is known regarding the mechanisms of action of longjack. Recent studies indicate that the root contains several compounds including beta-carboline alkaloids and quassinoid-type glycosides. How these compounds and many others in Tongkat Ali influence the human sexual response is not clearly understood at this time. I have read promotional material by some vitamin companies regarding longjack that it enhances testosterone production, however I have not been able to definitively confirm this claim through a Medline search.

Availability, sold in vitamin stores, online, GNC, iHerb, Amazon, Vitacost, Swanson vitamins, Puritan
Tongkat ali is sold as a powder, and in capsules, sometimes mixed with other herbs. There are a number of extracts available in various potencies, and since each company will have a different way of extracting, it is difficult to give dosages that would be consistently effective.

Longjack side effects, adverse reactions
High doses of longjack cause insomnia and increased body temperature along with a speedy heart beat. Long term effects on human consumption are not known.

Longjack Research
Cytotoxic and antimalarial constituents from the roots of Eurycoma longifolia.
Kuo PC, Damu AG, Lee KH, Wu TS.
Department of Chemistry, National Cheng Kung University, Tainan 701, Taiwan, ROC.
Bioorg Med Chem. 2004.
Sixty-five compounds were isolated from the roots of Longjack  and characterized by comprehensive analyses of their 1D and 2D NMR, and mass spectral data. Among these isolates, four quassinoid diterpenoids were reported from natural sources for the first time, namely eurycomalide A (1), eurycomalide B (2), 13beta, 21-dihydroxyeurycomanol (3), and 5alpha, 14beta, 15beta-trihydroxyklaineanone (4). Screening of cytotoxicity, anti-HIV and antimalarial activity of these isolated compounds was also furnished by in vitro assays. Compounds 12, 13, 17, 18, 36, 38, 59, and 62 demonstrated strong cytotoxicity toward human lung cancer (A-549) cell lines, however, 12, 13, 17, 38, 57, 58, and 59 exhibited strong cytoxicity toward human breast cancer (MCF-7) cell lines. Compounds 57 and 58 displayed potent antimalarial activity against the resistant Plasmodium falciparum. The thorough studies on the stereochemistry of the different quassinoid diterpenoids provide a clear reference to the scientists who are interested on this field.