Traditional uses:
Tribulus Terrestris has been used in past centuries for improving sexual function in both men and women, improving stamina and endurance and promoting a generalized feeling of well-being.

Physiology:
Tribulus terrestris increases muscle mass and improves erections by increasing testosterone levels in a unique fashion. Unlike, dehydroepiandrosterone (DHEA) or Androstenedione, which simply act as testosterone precursors, Tribulus terrestris increases testosterone levels by increasing the levels of Lutenizing Hormone (LH). LH is responsible for signaling the leydig cells in the testes to release testosterone.

Studies have shown an increase in excess of 50% testosterone levels when taking the Tribulus terrestris herb. The increase in testosterone levels will promote protein synthesis, positive nitrogen balance as well as a quicker recovery from muscular stress. The plant has also been shown to increase in sperm production and motility.

Clinical studies:
An interesting correlation of dehydroepiandrosterone-sulphate (DHEA-S) level with the incident of low sex drive and higher occurrence of impotence was discovered in studies with patients diagnosed with diabetes mellitus.  In order to test the further relationship between DHEA-S and erectile dysfunction, a clinical trial was done with 30 non-diabetic men with Erectile Dysfunction, 30 non-diabetic men without Erectile Dysfunction and 15 diabetic men with Erectile Dysfunction.  These men are given extract of Tribulus terrestris (Libilov) at 3 x 250 mg / day for 3 weeks. The DHEA-S levels, as well as other blood and liver parameters were evaluated.

Clinicians found a significant increase of DHEA-S levels in diabetic and non-diabetic subjects after treatment, and a significant increase in the frequency of successful intercourse by 60% in both the diabetic and non-diabetic groups with or without Erectile Dysfunction. Protodioscin from herbal plant tribulus terrestris L improves the male sexual functions, probably via the DHEA. Adimoelja A, Ganeshan P. Adaikan A University, Indonesia and National University of Singapore in 6th Biennial Asian-Pacific Meeting on Impotence in Kuala Lumpur, Malaysia (1997)Int. J. Impotence Research v9, supp 1 (1997)

In another study clinicians investigated the effects of Tribulus terrestris L. on sperm morphology and acrosome reaction in subjects with oligoasthenoteratozoospermia. A double-blind placebo-controlled trial was performed with 30 primary and secondary infertile men. Half received oral Tribulus three times per day for 60 days, and the rest were given sugar pills. The ejaculate volume, sperm concentration, morphology, acrosome reactions, and other parameters were evaluated before and after treatment.

A significant increase in the percentage of slow or sluggish progressive motile sperm in the treated group was observed when compared to the control group. The percentage of the sperm with normal acrosome (a process at the anterior end of a sperm cell that produces enzymes to facilitate penetration of the egg) reaction was also increased, whereas, the percentage of immotile sperm decreased significantly. The frequency of sexual intercourse was also increased significantly in the Tribulus group. The study concluded that Tribulus terrestris L., given at 500mg three times a day for 60days proved to be effective in restoring some of the sperm functions, such as motility and acrosome reactions.

Tribulus terrestris L. extract improves spermatozoa motility and increases the efficiency of the acrosome reaction in subjects diagnosed with oligoasthenoteratozoospermia L. Setiawan Airlangga University, Surabaya, Indonesia (1996).

Modern day uses:
Today, Tribulus terestris is prescribed by physicians and herbal specialist for the following:

• Increase spermatozoa motility
• Treatment of erectile dysfunction (impotence)
• Increase testosterone levels
• Diseases of genito urinary tract including dysuria chronic cystitis, phosphaturia, incontinence, etc
• Spermatorrhoea (Involuntary discharge of semen without orgasm)
• Immune system deficiencies
• Uterine disorders after parturition

Precautions and/or adverse effects:
Individuals with preexisting medical conditions should consult with their physician particularly if they are taking prescription or over-the-counter-medications or supplements. Women who are pregnant or breast feeding and children should also consult with there physician prior to taking any new supplements. Very few side effects have been reported with the use of Tribulus terrestris except for periodic cases of an upset stomach at the time of this writing. This situation can usually be avoided if individuals take the herb on a full stomach.

Please note: The above information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist, or other healthcare professionals. The information should not be construed to indicate that the use of the product is appropriate, safe, or effective for each individuals use. Individuals should consult their healthcare professional prior taking any new product.