Tribulus terrestris

Tribulus Terrestris: A Comprehensive Reference

1. Identity, Taxonomy, and Nomenclature

Tribulus terrestris L. (commonly abbreviated TT) is an annual plant of the family Zygophyllaceae. Its full accepted botanical name is Tribulus terrestris Linnaeus. The plant is known variously as "Tribulus," "puncture vine," "caltrop," "goat head," "puncture weed," "Mexican sandbur," "Texas sandbur," or "bullhead," among other names. In traditional medicine systems in China and India (Ayurveda), it is known as bai ji li and gokshura, respectively.

Gokshura is a low-growing, herbaceous plant that typically reaches a height of about 1 to 2 feet (30 to 60 centimeters). It has small, yellow flowers with five petals and spiky fruits covered in sharp thorns, which give it the nickname "puncture vine." TT predominantly grows in the countries around the Mediterranean Sea and in sub-tropical regions around the world. The general spread of Tribulus terrestris L. includes South Africa, Australia, Europe, and India. It has a high content of active ingredients, in particular sterol saponins, as well as flavonoids, tannins, terpenoids, phenol carboxylic acids, and alkaloids, and it is frequently used in folk medicine and as a food supplement.

Common Preparations and Dosage Forms

Dietary supplements that contain tribulus are made from the leaf, stem, fruit, and root of the plant. Tribulus is available in tablets and capsules of 250 and 500 mg, and the usual daily dose reported is 250 to 750 mg daily. Tribulus terrestris is also included in many multi-ingredient dietary supplements used for sexual dysfunction and bodybuilding. Standardized extracts are typically characterized by their steroidal saponin content, often expressed as a percentage of the dry extract.

2. Traditional and Historical Use

The fruits and roots of Tribulus terrestris, alone or in combination with other medicinal plants, have been used as a folk medicine for five thousands of years in various Asiatic countries. The fruits and roots of TT have been used as a folk medicine for thousands of years in China, India, Sudan, and Pakistan.

Ayurvedic Medicine (India)

In Ayurvedic medicine, its application is recommended for the treatment of urinary affection, urinary calculi, polyuria, dyspnoea, cough, piles, dysuria, heart disease, and as a gastric stimulant. In India, the fruits have been used in the treatment of infertility, impotence, erectile dysfunction, and low libido in Ayurveda. Classified as a rasayana (rejuvenator) in Ayurvedic medicine, tribulus has been traditionally used to support energy, stamina, and overall vitality.

Traditional Chinese Medicine (TCM)

In native Chinese medicine, the leaves of Tribulus terrestris are used for treatment of stomach problems, bladder stones, male reproductive disorders, and ocular diseases. TT is commonly known as "Hard thorns" and "goat head" in China. In TCM, tribulus was first documented in the Shen Nong Ben Cao Jing around 71 AD, one of the earliest Chinese medicine texts.

Unani (Greco-Arabic) and Other Traditional Systems

Tribulus has a long history of use as a herbal medicine by Chinese, Unani (Arabic), and Ayurvedic (Indian) systems of medicine. It is primarily used in these systems of medicine as a diuretic and in the treatment of kidney stones, urinary tract infections, and incontinence. T. terrestris is used in various traditional medical practices, including Ayurveda, Traditional Chinese Medicine, and Siddha, as a diuretic, aphrodisiac, immunomodulatory, anti-urolithic, antibacterial, anti-hyperlipidemic, antidiabetic, hepatoprotective, anticancer, anti-hypertensive, anthelmintic, analgesic, and anti-inflammatory agent.

3. Key Constituents and Active Compounds

Many different compounds with a variety of biological properties and chemical structures have been identified from TT, including steroidal saponins, phytosterols, phenolic compounds, tannins, terpenoids, amide derivatives, amino acids, and proteins. The main biologically active substances in TT are steroidal saponins, flavonoids, alkaloids, and lignan amides, with the steroidal saponins being the most studied.

Steroidal Saponins

Spirostanol and furostanol saponins are considered the most characteristic chemicals in TT. To date, 108 kinds of steroidal saponins have been isolated from TT: 58 kinds of spirostane saponins and 50 kinds of furostane saponins. The steroidal saponins, such as protodioscin and protogracillin, are thought to confer TT its unique biological activities.

Key bioactive constituents identified include flavonol glycosides, steroidal saponins, flavonoids, alkaloids, protodioscin, terrestrosins A and E, gitonin, β-sitosterol, tigogenin, spirosta-3,5-diene, diosgenin, stigmasterol, hecogenin, and kaempferol.

Phytochemical studies have shown great disparities in the content of active substances, in particular the concentration of furostanol and spirostanol saponoside, considered to be the predominant active ingredients. Studies have revealed that the composition is strictly linked with the origin of the plant, and hence with climatic conditions. Geographical regions significantly influence the composition of herbal drugs. Dinchev et al. detected prototribestin only in samples collected from Bulgaria, Turkey, Greece, Macedonia, Iran, and Serbia, but no protodioscin was detected in the samples collected from Vietnam and India. It appeared that prototribestin could be a marker for the European variety of TT.

Flavonoids and Other Phenolics

T. terrestris contains various bioactive metabolites, including steroidal saponins, flavonoids, and alkaloids. These metabolites exhibit anti-inflammatory, antioxidant, and antibacterial properties, and tyrosinase-regulating effects, making T. terrestris a promising candidate for treating multiple disorders. Sterols in the aerial parts are represented by sitosterol, stigmasterol, and campesterol.

Lignan Amides and Alkaloids

Li et al. isolated tribulusamides A and B, lignan amides, in TT fruits. These compounds have been shown to protect cells in the presence of tumors induced by D-galactosamine/tumor necrosis factor α (TNF-α). Ren et al. and Jain and Gupta identified new derivatives of the cinnamic acid amides in fruits: terrestriamide (I) and 7-methylhydroindanone-1 (II). Li et al. and Zhang et al. isolated a new lignan amide from TT fruits, a feruloyl amide derivative called tribulusamide C.

4. Mechanisms of Action

Hypothesized Androgenic Pathway

It is believed that T. terrestris can enhance testosterone levels by stimulating the release of gonadotropin-releasing hormone (GnRH), which in turn triggers the production of follicle-stimulating hormone (FSH) and luteinizing hormone (LH). Extracts of T. terrestris standardized for protodioscin content have been shown to produce pro-erectile effects in isolated tissues and aphrodisiac activity in several animal models. Protodioscin is thought to contribute to increased androgen receptor immunoreactivity in some tissues, likely as a secondary effect of elevated levels of endogenous androgens such as testosterone and dihydrotestosterone (DHT).

Literature data shows that steroidal saponins are responsible for the major biological activities related to TT use. The steroidal molecular structure of steroidal saponins such as protodioscin is thought to confer TT its unique biological activities. It is important to note, however, that the precise molecular mechanisms have not been fully confirmed in human clinical studies.

Saponin-Mediated Anti-Inflammatory and Immune Effects

Saponins have several important biological functions. They have been demonstrated to possess anti-inflammatory effects through the activation of macrophages and other immune cells, thereby modulating the immune system.

Antidiabetic Mechanisms

The gross saponins of T. terrestris (GSTT) showed inhibitory activity against α-glucosidase. In addition, they showed inhibitory activities on postprandial blood glucose increase and improvement in insulin-dependent diabetes symptoms. Animal experiments indicated that GSTT significantly reduced the postprandial blood glucose levels by intragastric administration of sucrose in normal rats and type 2 diabetic rats, but did not affect the postprandial blood glucose levels of the rats with intragastric administration of glucose.

Overall Mechanistic Uncertainty

Studies of experimental pharmacology (in vitro and animal models in vivo) and clinical pharmacology (efficacy and safety clinical trials) have sometimes led to divergent results; moreover, the presumed pharmacodynamic mechanisms have yet to be confirmed by molecular biology studies. Tribulus contains chemicals called steroidal saponins that are thought to have effects in the body. It has been proposed that these chemicals may increase testosterone levels or help to stimulate certain receptors in the kidneys or brain. But the actual effects of these chemicals are not well understood, and research on any use is mixed or limited.

5. Scientific Evidence by Area of Use

5.1 Male Sexual Function and Erectile Dysfunction

Tribulus terrestris L. is a plant that has been claimed to increase testosterone levels and improve sexual function, particularly erectile dysfunction, with potential benefits for male sexual health. A 2025 systematic review aimed to evaluate the effectiveness of TT supplementation in improving sexual function and serum testosterone levels in men.

After searching 162 publications, 52 studies were selected for full-text reading, and 10 studies were eligible for this review, comprising 9 clinical trials and 1 quasi-experimental study. The Jadad score revealed low methodological quality for 50% of the studies. The studies involved 15 to 172 participants (total = 483) aged between 16 and 70 years with different health conditions: healthy men (n = 5), oligozoospermia (n = 1), erectile dysfunction (n = 1), erectile dysfunction associated with hypogonadism (n = 2), and unexplained infertility (n = 1).

TT supplementation at doses of 400 to 750 mg/d for 1 to 3 months improved erectile dysfunction in 3 of the 5 studies that assessed this parameter. Eight out of ten studies did not report significant changes in androgen profile following TT supplementation, but the subjects in the neutral studies did not have low androgen levels at baseline. Only 2 studies showed significant intra-group increases in total testosterone levels, which had low clinical magnitude (60–70 ng/dL) and involved subjects with hypogonadism.

Evidence strength: Overall evidence quality for male erectile dysfunction and testosterone elevation is weak to moderate. Most positive findings were in men with pre-existing low testosterone, and the body of clinical literature is methodologically heterogeneous with many studies of low quality.

5.2 Female Sexual Dysfunction

A systematic review was performed to assess the effectiveness and safety of Tribulus terrestris for female sexual dysfunction (FSD), searching multiple electronic databases without restriction. Five randomized controlled trials (RCTs) totaling 279 participants were included.

After 1 to 3 months of treatment, premenopausal and postmenopausal women randomized to T. terrestris had a significant increase in sexual function scores. Three months of treatment showed a significant increase in serum testosterone levels of premenopausal women. There was no report of serious adverse events. Due to lack of data and clinical heterogeneity, meta-analyses could not be performed. The certainty of the evidence was very low, which means there is very little confidence in the effect estimates, and future studies are likely to change these estimates. More RCTs are needed to support or refute the use of T. terrestris.

One individual RCT examined tribulus in women with hypoactive sexual desire disorder (HSDD): this randomized double-blind placebo-controlled trial assessed the safety and efficacy of Tribulus terrestris in women with hypoactive sexual desire disorder during their fertile years. Sixty-seven women with HSDD were randomly assigned to Tribulus terrestris extract (7.5 mg/day) or placebo for 4 weeks. Thirty women in each group completed the study. At the end of the fourth week, patients in the Tribulus terrestris group had experienced significant improvement in their total FSFI score (p < 0.001) and in desire (p < 0.001) and arousal (p = 0.037).

A separate uncontrolled study of 120 women of reproductive age treated with 250 mg Tribulus terrestris extract three times daily for 90 days found: there was a statistically significant improvement in total FSFI scores (P < 0.0001) post-treatment, with improvement among 106 (88.33%) subjects. There was a statistically significant (P < 0.0001) increase in the level of DHEA, while the levels of both serum testosterone and free testosterone decreased (P < 0.0001). The absence of a control arm in that study significantly limits its interpretability.

Evidence strength: Preliminary and based on a small number of low-certainty RCTs. Signal for benefit in sexual function scores exists, but confidence in effect estimates is very low by GRADE assessment.

5.3 Testosterone Levels in Healthy Men and Athletes

Today, TT is widely used by athletes and bodybuilders based on the belief, fueled by claims in marketing information, that it can enhance testosterone concentrations. A systematic review covering the literature through August 2013 identified randomized controlled trials in healthy humans and animal studies. The results showed that trials varied in duration, dosage, and supplementation with TT as sole or combined treatment, rendering meta-analysis impossible.

In a randomized, single-blind, placebo-controlled trial in CrossFit athletes: 30 healthy CrossFit®-trained males were randomly allocated to receive either 770 mg of TT supplementation or a placebo daily for 6 weeks. Body mass, fat mass, fat composition, testosterone and cortisol levels, and CrossFit® performance were assessed before and after intervention. There were no significant group × time interactions for most outcomes except for testosterone levels and bench press performance (p < 0.05). TT supplementation did not enhance overall performance or body composition in CrossFit® male athletes.

A separate crossover study: Thirteen university-student athletes (mean age 23.9 ± 2.1 years) participated in a randomized, double-blind, crossover study. Participants received either a daily oral supplement of Tribulus terrestris L. (20 mg·kg⁻¹ × 3 times per day) for 4 weeks or a placebo with a 2-week wash-out period between trial periods. The study found that TT failed to improve exercise performance and body composition following a detraining period.

The 2025 PRISMA systematic review further confirmed that eight out of ten clinical studies did not report significant changes in androgen profile following TT supplementation, particularly in healthy men with normal baseline androgen levels.

Evidence strength: The weight of current clinical evidence indicates that TT does not meaningfully raise testosterone in healthy men with normal baseline levels. Any statistically significant increases have been confined largely to men with hypogonadism and are of limited clinical magnitude.

5.4 Urolithiasis (Kidney Stones)

Tribulus extract was shown to limit formation of calcium oxalate and calcium hydrogen phosphate dihydrate crystals, mineral compounds that can cause kidney stones, in preclinical laboratory studies. Urine volume and phosphate level in the serum were not significantly altered in urolithic patients. It was concluded that TT extract was useful in the treatment of urolithiasis — however, the body of evidence for this indication in humans remains limited primarily to preclinical studies and a small number of clinical reports.

In a preclinical study in Wistar rats, an aqueous extract of TT demonstrated antiurolithic efficacy: treatment showed augmented renal function, restoration of normal renal architecture, and increase in body weight. The acute oral toxicity study established the median lethal dose (LD₅₀) at greater than 2000 mg/kg body weight, and no observed adverse effect level (NOAEL) was identified with repeated oral dosing at 750 mg/kg body weight for 28 days.

Evidence strength: Preclinical evidence in animal models is moderately consistent; robust human RCT data for antiurolithic effects is lacking.

5.5 Antidiabetic Effects

Clinical trials proved that the water extract of T. terrestris (WETT) has antidiabetic activity. In an experimental animal model in diabetic rats, both TT preparations reduced elevated blood glucose levels. Insulin and luteinizing hormone levels were not significantly different compared with the control group; however, FSH and testosterone levels were significantly higher in the high protodioscin content group compared with the diabetic control group.

Evidence strength: Preliminary. Antidiabetic effects have been shown in animal models and limited clinical data. High-quality, adequately powered human RCTs are lacking.

5.6 Cardiovascular and Lipid Effects

Because of its potassium-sparing, cardioprotective, and anti-hyperlipidemic properties, T. terrestris may have the potential of herbal therapy for successful blood pressure control. It has been reported that TT has a wide range of positive effects including diuretic, aphrodisiac, antiurolithic, immunomodulatory, antidiabetic, absorption-enhancing, hypolipidaemic, cardiotonic, neurotonic, hepatoprotective, antioxidant, anti-inflammatory, analgesic, antispasmodic, anticancer, antibacterial, anthelmintic, larvicidal, and anticariogenic effects — but there is little evidence for the large majority of such claims.

Evidence strength: Claimed cardiovascular benefits are largely based on limited preclinical work and traditional use. Robust human clinical evidence is currently insufficient to support specific cardiovascular indications.

5.7 Skin Conditions

T. terrestris L., a traditional medicinal plant, has garnered increasing attention for its potential in treating skin diseases. Studies have shown its potential efficacy against conditions such as atopic dermatitis, acne, and vitiligo. However, several limitations remain: its precise mechanisms of action in skin diseases are not yet fully elucidated, its standalone efficacy for complex skin diseases may be limited, and there is a lack of high-quality, large-scale clinical trials to conclusively verify its efficacy and safety.

Evidence strength: Preliminary; largely in vitro and animal models, with insufficient human clinical trial data.

6. Body Systems and Health Areas Associated with Tribulus Terrestris

• Reproductive system (male and female): T. terrestris can act as a stimulator of male and female reproductive processes at the level of the central nervous system, sexual behaviour, pituitary and gonadal hormones and their receptors, gonadal functions (including ovarian folliculogenesis and spermatogenesis), and improvement of the quality and quantity of gametes.
• Urinary system: Used traditionally and studied for diuretic and antiurolithic properties, particularly against calcium oxalate kidney stones.
• Endocrine/hormonal system: Proposed interactions with LH, FSH, testosterone, DHEA, and insulin pathways, primarily via steroidal saponins.
• Cardiovascular system: Pharmacological activities explored include anti-hypertensive, anti-hyperlipidemic, and immunomodulatory effects.
• Metabolic/glycaemic: Studied for antidiabetic properties including α-glucosidase inhibition and blood glucose reduction in animal models.
• Integumentary system (skin): Emerging preclinical data on anti-inflammatory, antioxidant, antibacterial, and tyrosinase-regulating roles.
• Immune system: Saponins from TT have been demonstrated to possess anti-inflammatory effects through the activation of macrophages and other immune cells, thereby modulating the immune system.

7. Dosages Reported in Clinical Studies

Dosages reported across clinical studies vary considerably by preparation, plant part, and indication:

• Tribulus is available in tablets and capsules of 250 and 500 mg, and the usual daily dose is 250 to 750 mg daily.
• TT supplementation at doses of 400 to 750 mg/d for 1 to 3 months was used in clinical trials assessing erectile dysfunction.
• In one RCT for female HSDD, Tribulus terrestris extract was administered at 7.5 mg/day for 4 weeks.
• One clinical study used 250 mg Tribulus terrestris extract administered as 1 tablet three times daily (750 mg/day total) for 90 days for female sexual dysfunction.
• One randomized controlled trial in CrossFit® male athletes used 770 mg of TT supplementation daily for 6 weeks.
• A crossover athlete study used 20 mg·kg⁻¹ administered 3 times per day for 4 weeks.

Given the differences observed in the composition, the plant organ used to obtain the extract, the need for selective extraction methods, and the standardization of T. terrestris extracts is an absolute necessity for meaningful comparison across studies. The large variation in saponin content by geographic origin makes cross-study dosage comparisons unreliable without standardization data.

8. Safety Considerations and Interactions

General Tolerability

Tribulus is reported to be well tolerated but may be associated with mild gastrointestinal discomfort, nausea, or dyspepsia. In clinical trials for female sexual dysfunction, there was no report of serious adverse events.

Hepatotoxicity — Case Reports

Tribulus is a herbal product prepared from the leaves, fruit, and roots of Tribulus terrestris, extracts of which have been used as an aphrodisiac, general tonic, and mood stimulant in traditional medicine. The native plant causes serious liver injury in grazing animals, but tribulus extracts have not been linked convincingly to instances of clinically apparent liver injury when given in typical doses in humans.

Despite this generally reassuring regulatory position, individual case reports have documented serious outcomes:

• One case describes a 46-year-old man who took tribulus supplements daily for 2 months. He developed severe jaundice prompting hospital admission. His total bilirubin peaked at 48 mg/dL, with concomitant renal dysfunction (creatinine of 7.1). His liver biopsy showed features consistent with drug-induced liver injury.
• Another case described severe hyperbilirubinemia in a healthy 30-year-old male bodybuilder, followed by acute renal failure and bile-containing casts in the tubules, associated with ingestion of tribulus extract tablets once daily for "a few months."
• A further case reported neuro-, hepatic, and renal toxicity suggestive of acute tubular necrosis (ATN) in a 28-year-old man who consumed large quantities of tribulus extract; he also developed hypertension, seizures, and markedly elevated serum aminotransferases (>40× ULN).

The steroidal saponin diosgenin is thought to be responsible for hepatotoxic effects associated with tribulus.

Tribulus has been linked to liver injury and death in animals in a phenomenon described as "geeldikkop" or tribulosis. Animals grazing on different tribulus species can develop marked photosensitivity and icterus, followed by severe jaundice and death. Histology of the liver from sheep dying after feeding on this plant has shown crystals in bile ducts and renal tubules.

Renal Toxicity

A case of Tribulus terrestris toxicity in a young healthy male presented with severe hyperbilirubinemia followed by acute renal failure and bile-containing casts in the tubules. Tribulus terrestris is an herb often used by athletes as a nutritional supplement for performance enhancement. Although it is thought to be relatively safe, serious side effects have been reported.

Isolated case reports of renal injury with serum aminotransferase elevations have been published but may have represented instances of ischemic or anabolic steroid-induced liver and kidney injury rather than direct hepatotoxicity of the extract.

Neurological Toxicity (Animal Data)

Consumption of tribulus causes motor neuron adverse effects in animals by affecting the gamma-aminobutyric acid (GABA) receptors. The direct relevance to human supplementation at typical doses has not been established.

Drug Interactions

• Diuretics: Tribulus may increase the effects of other diuretic drugs. Clinical relevance is not known.
• Statins (e.g., atorvastatin): There is documentation of rhabdomyolysis occurring from a potential interaction between Tribulus terrestris and atorvastatin. This may put patients at increased risk of developing serious adverse effects, including rhabdomyolysis and drug-induced liver injury. The proposed mechanism involves CYP3A-mediated interactions.
• Antidiabetic agents: Given preclinical evidence of blood glucose-lowering effects, additive hypoglycaemic effects with antidiabetic drugs are a theoretical concern.

Priapism

Priapism lasting 72 hours was reported in a 36-year-old Caucasian man following consumption of tribulus. The patient underwent a cavernoglandular shunt (Ebbehoj shunt), which had negative post-episode outcomes on sexual function.

Regulatory and Quality Considerations

Over-the-counter supplement use is a very common practice. Supplements are not tightly regulated by the Food and Drug Administration. There are many case reports involving OTC supplement adverse effects and medication interactions, but there remains minimal clinical research regarding these subjects. The large variability in saponin content across geographical origins further complicates the assessment of dose-response relationships and safety thresholds.

References

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