Tribulus terrestris is a flowering plant in the family Zygophyllaceae, native to warm temperate and tropical regions of the Old World in southern Europe, southern Asia, throughout Africa, and in northern Australia. It can thrive even in desert climates and poor soil.

Dietary supplement

Tribulus terrestris has long been used as a tonic and aphrodisiac in Indian ayurveda practice, where it is known by its Sanskrit name, “gokshura”.

It is now being promoted as a testosterone booster for the purpose of building muscle and increasing sex drive. Independent studies have suggested that Tribulus terrestris extract does increase testosterone levels, though leaving them in the normal range, which is not thought to increase muscle development.

Some have compared the tonic properties of Tribulus terrestris to the effects of ginseng, but these occur due to entirely different mechanisms. Claims have been made that it enhances testosterone levels by increasing luteinizing hormone (LH) levels. LH is responsible for “telling” your body to produce testosterone. One interesting fact is that extended use of anabolic steroids reduces levels of LH, thus reducing and sometimes shutting down the body’s production of testosterone.

It is also claimed that Tribulus terrestris increases testosterone by increasing gonadotropin-releasing hormone (GnRH) which in turn stimulates the production of LH and follicle-stimulating hormone (FSH). Testosterone, besides its role in muscle-building and raising fertility and libido, is also known to have a positive effect on bone marrow activity (for red blood cell production) and the immune system.

On the other hand, one recent study found that T. terrestris caused no increase in testosterone or LH in young men, and another found that a commercial supplement containing androstenedione and herbal extracts, including T. terrestris, was no more effective at raising testosterone levels than androstenedione alone. SupplementWatch does not consider that there is any scientific evidence for effectiveness in muscle building. It suggests that it may be beneficial for those whose testosterone is below normal, such as dieters and overtrained athletes.

No significant adverse effects have been reported from supplementation with Tribulus terrestris. However, some users report an upset stomach, which can usually be counteracted by taking it with food.