I have tested Tongkat Ali from several other sources before using the one from Sumatra Pasak Bumi (www.tongkatali.org). I didn't have much immediate effect. But I sure feel an immediate effect with 1 gram of 1:50 extract from Sumatra Pasak Bumi. It's like a mixture of the effects of St. John's Wort extract and the synthetic testosterone Proviron. I feel some agitation in the head, a kind of hot-bloodedness, which I feel from Proviron, and the sublime agility caused by St. John's Wort.

I have never had a weak ejaculation after ingesting 1 gram of the Sumatra Pasak Bumi 1:50 extract. I assume that ejaculatory force diminishes for any man as he reaches an age of around 50 and beyond, and in that case I am no exception.

The marked ejaculatory support is a measurable pro-sexual effect of the Tongkat Ali extract I use.

I am a scientifically minded person. I like to observe, but even more I like to use measuring tapes, balances, chemical tests, and all the other tools of the laboratory trade.

Tongkat Ali has been shown to increase testosterone. It is alleged that it does so by stimulating the Leydig cells of the testicles to produce more testosterone. This is different from the action, for example, of Proviron, which acts like the body's own testosterone and therefore causes the Leydig cells to shut down their production of the hormone. For this reason, anabolic steroids cause testicular and penile shrinkage.

In a toxicological study with various laboratory animals the LD50 values of tongkat ali were established for mice, rats, rabbits, and dogs. LD50 means: the dose at which 50 percent of the laboratory animals die. The LD50 values are at more than a gram of extract per kg of body weight.

When the Tongkat Ali-poisoned animals where dissected, several internal organs, such as the liver and the kidneys, were clearly swollen. This is not surprising for any LD50 test, as the above-cited organs are directly involved in the metabolism of ingested substances. More interesting was, in my opinion, that the primary male sexual organs of poisoned laboratory animals also were markedly swollen. This is very unusual.

Testicular and penis size are clearly testosterone-dependent. Every bodybuilder who uses steroids, and thereby shuts down his body's own testosterone production, can easily observe how the inactivity of his Leydig cells cause testicular and penile shrinkage. And it's a spur in Leydig cell activity, which, during puberty, causes a boy's sexual organs to become the size of a man's. Furthermore, testosterone over-production endocrine disorders during adolescence cause oversized male genitalia.

The assumption that tongkat ali extract causes an increase in penile and testicular volume through Leydig cell stimulation is further supported by observations of trial participants who reported a sense of testicular and penile fullness after tongkat ali use.