Tribulus
*Tribulus terrestris*
Evidence Rating
Confidence Level
Traditions
Last Updated
Summary
Tribulus terrestris is widely marketed as a testosterone booster and performance enhancer, but clinical evidence does not support testosterone-increasing effects. A 2025 systematic review of 10 studies found that 8 out of 10 studies showed no significant change in androgen levels. There is limited evidence (low quality) for modest improvement in sexual function and erectile dysfunction at doses of 400-750 mg/day, potentially through mechanisms unrelated to testosterone. The herb contains steroidal saponins, primarily protodioscin, whose concentration varies significantly by geographic origin (Bulgarian varieties have the highest content). In Ayurveda it is known as Gokshura and used as a urinary and reproductive tonic. No Commission E, ESCOP, or EMA monograph exists. The safety profile appears generally favorable at standard doses, though liver and kidney toxicity have been reported at high doses in case reports.
Drug Interactions
This herb has significant drug interactions. Do not use if you are taking medications without consulting a healthcare provider first. See detailed interaction information below.
Regulatory Status
| Regulatory Body | Status |
|---|---|
| Commission E (Germany) | — |
| ESCOP (European) | — |
| EMA/HMPC (EU) | — |
Metadata
| Field | Detail |
|---|---|
| Common Names (English) | Tribulus, Puncture Vine, Caltrop, Bindii |
| Common Names (Sanskrit/Ayurvedic) | Gokshura, Gokharu |
| Botanical Name | Tribulus terrestris L. |
| Plant Family | Zygophyllaceae (Caltrop family) |
| Part Used | Fruit (primarily), aerial parts; root used in some Ayurvedic preparations |
| Key Constituents | Steroidal saponins (furostanol and spirostanol types): protodioscin, protogracillin, tribulosaponins; flavonoids (kaempferol, quercetin glycosides); alkaloids (harmine, harman); phytosterols (beta-sitosterol, stigmasterol) |
| Major Standardized Extracts | Extracts typically standardized to 40-60% total saponins and/or minimum 6% protodioscin; no single universally recognized standardized extract |
| Evidence Quality Rating | Fair — limited, low-to-moderate quality RCTs; testosterone claims not substantiated |
Approved Indications
Commission E (Germany)
- No Commission E monograph has been published for Tribulus terrestris
ESCOP
- No ESCOP monograph has been published for Tribulus terrestris
EMA/HMPC (European Medicines Agency)
- No EMA/HMPC monograph has been published for Tribulus terrestris
Agreement/Disagreement Between Bodies
- No regulatory approval: None of the major European herbal regulatory bodies have assessed or approved tribulus
- Notable: Tribulus is primarily marketed through the sports supplement and men’s health supplement industries rather than as a phytomedicine in the European tradition
- Ayurvedic context: Gokshura has established traditional use in Ayurveda, but this does not translate to European regulatory recognition
Conditions Treated
Primary (Moderate Evidence)
- Sexual dysfunction in men (libido, erectile function): Limited evidence from small RCTs suggests modest improvement in sexual function scores, though the evidence quality is low
Secondary (Limited Evidence)
- Female sexual dysfunction: Some preliminary evidence for improvement in desire and satisfaction
- Lower urinary tract symptoms (LUTS): Traditional and limited clinical use, particularly in Ayurveda (Gokshura is traditionally used for urinary complaints)
Traditional/Historical (Limited Evidence)
- Urolithiasis (kidney stones) — Ayurvedic use as Gokshura
- Male infertility (improving sperm parameters — preclinical data)
- Adaptogenic and tonifying effects (Ayurvedic tradition)
- Athletic performance enhancement (not supported by clinical data)
- Testosterone enhancement (not supported by clinical data — see below)
Debunked Claims
- Testosterone boosting: Multiple systematic reviews and clinical trials have consistently failed to demonstrate that Tribulus terrestris increases testosterone levels in humans. This is the most widely marketed claim and it is not supported by evidence. Of 10 clinical studies reviewed in a 2025 systematic analysis, 8 showed no significant change in androgen profiles. The 2 studies showing any increase involved men with hypogonadism and the increases were of low clinical magnitude (60-70 ng/dL)
Mechanism of Action
Primary Mechanisms
Potential Sexual Function Effects (Not via Testosterone):
- Protodioscin may enhance nitric oxide release from corpus cavernosum endothelium, improving erectile function through a mechanism independent of testosterone
- Steroidal saponins may modulate androgen receptor sensitivity or downstream signaling without increasing circulating testosterone levels
- Potential effects on DHEA (dehydroepiandrosterone) metabolism have been proposed but are not confirmed in clinical studies
Ayurvedic Pharmacological Rationale (Gokshura):
- In Ayurveda, Gokshura is classified as a Mutrala (diuretic) and Vajikara (aphrodisiac)
- Traditional actions include balancing Vata and Pitta doshas, supporting kidney and urinary function, and nourishing reproductive tissues (Shukra dhatu)
Secondary Mechanisms
| Compound | Activity |
|---|---|
| Protodioscin | Proposed nitric oxide enhancement in erectile tissue; most pharmacologically active saponin; concentration varies by geographic origin |
| Furostanol saponins (total) | Structural similarity to steroid hormones; potential membrane receptor interactions |
| Beta-sitosterol | Mild 5-alpha-reductase inhibition (preclinical); anti-inflammatory |
| Flavonoids (kaempferol, quercetin) | Antioxidant, anti-inflammatory |
| Harmine/Harman alkaloids | MAO inhibition (preclinical); potential mood-modulating effects |
Geographic Variation in Composition
- Protodioscin content varies dramatically by region of cultivation: Southeastern European (Bulgarian) varieties contain the highest concentrations of protodioscin, while Asian varieties contain substantially less
- This geographic variation complicates the interpretation of clinical studies, as the saponin profile and potency differ between products
Clinical Evidence Summary
Volume of Evidence
- Limited. A 2025 systematic review identified 10 eligible studies (9 clinical trials and 1 quasi-experimental study), with methodological quality rated as low for 50% of the studies.
Key Studies
Sexual Function and Erectile Dysfunction
| Study | Design | N | Key Finding |
|---|---|---|---|
| Kamenov et al. 2017 | RCT, DB, PC | 180 | 750 mg/day Tribulus extract for 12 weeks improved sexual desire and erectile function in men with mild-to-moderate ED |
| GamalEl Din et al. 2019 | RCT, DB, PC | 30 | 750 mg/day for 3 months showed no significant improvement in erectile function compared to placebo in men with late-onset hypogonadism |
| Santos et al. 2014 | RCT, DB, PC | 30 | 800 mg/day for 30 days showed no significant effect on erectile dysfunction scores |
Testosterone Levels
| Study | Design | N | Key Finding |
|---|---|---|---|
| Systematic review (2025) | Review of 10 studies | Various | 8 of 10 studies showed no significant change in testosterone levels; 2 studies with positive results were in hypogonadal men and showed low-magnitude increases |
| Neychev & Mitev 2005 | RCT, DB, PC | 21 | 750 mg/day for 4 weeks in healthy men showed no effect on testosterone |
| Rogerson et al. 2007 | RCT, DB, PC | 22 | 450 mg/day for 5 weeks in resistance-trained men showed no effect on testosterone or body composition |
Female Sexual Dysfunction
- De Souza et al. 2016: In a systematic review, tribulus showed some evidence for improving sexual desire in women, though the number and quality of studies were limited
Evidence Gaps
- No European regulatory assessment
- Lack of large, well-designed RCTs
- Inconsistent standardization of extracts across studies (protodioscin content varies)
- No long-term safety or efficacy data
- Mechanism of any sexual function improvement remains unclear
- The geographic origin of the plant material is rarely specified in clinical studies, despite significant variation in active constituent concentrations
European vs US/Anglophone Consensus
| Aspect | European Consensus | US/Anglophone Consensus |
|---|---|---|
| Regulatory status | No regulatory monograph; not a registered herbal medicine; not part of mainstream European phytotherapy | Dietary supplement; widely marketed in sports nutrition and men’s health categories; no FDA therapeutic claims |
| Medicinal use | Limited clinical use; primarily available through supplement industry; Bulgarian research tradition focused on saponin characterization | Widely marketed as testosterone booster despite evidence to the contrary; one of the most popular men’s health supplements |
| Evidence perception | Recognized that testosterone claims are unfounded; limited interest in formal phytotherapy | Marketing often overstates evidence; systematic reviews increasingly cited to counter testosterone claims |
| Traditional context | Limited European ethnobotanical tradition; Bulgarian phytochemical research is notable | Ayurvedic tradition (Gokshura) recognized in integrative medicine circles |
| Marketing claims | Less aggressively marketed in Europe compared to US/global markets | Among the most marketed men’s health supplements; testosterone-boosting claims persist despite contrary evidence |
Safety Profile
Contraindications
- Known hypersensitivity to Tribulus terrestris or Zygophyllaceae plants
- Pre-existing liver disease or hepatic impairment (precautionary; case reports of hepatotoxicity at high doses)
- Pre-existing kidney disease (precautionary; potential nephrotoxicity at high doses)
- Hormone-sensitive conditions (theoretical concern due to steroidal saponin content, though clinical relevance is uncertain)
Drug Interactions
- Antihypertensive medications: Tribulus may have mild blood pressure-lowering effects; additive hypotension is theoretically possible
- Antidiabetic medications: Some evidence of blood sugar-lowering effects; monitor for hypoglycemia
- Lithium: Potential diuretic effect may alter lithium clearance
- P-glycoprotein substrates: In vitro data suggests tribulus saponins may inhibit P-gp activity, potentially increasing bioavailability of P-gp substrate drugs (digoxin, cyclosporine); clinical relevance is unknown
- Hepatotoxic drugs: Theoretical additive liver toxicity risk at high doses
Side Effects
- Generally well tolerated at standard doses (250-750 mg/day)
- Gastrointestinal upset (nausea, stomach discomfort) is the most commonly reported side effect
- Sleep disturbance reported occasionally
- Case reports of hepatotoxicity and nephrotoxicity exist, primarily at high doses or with prolonged use
- Elevated PSA (prostate specific antigen) reported in some studies, warranting caution in men with prostate conditions
Pregnancy/Lactation
- Pregnancy: Contraindicated. Steroidal saponin content presents a theoretical risk of hormonal disruption. Animal studies have shown reproductive toxicity at high doses. Must not be used during pregnancy
- Lactation: Insufficient safety data; not recommended during breastfeeding
- Children: Not recommended for use in children or adolescents
Clinical Dosage
Standard Dosage Forms
| Form | Preparation | Daily Dose | Notes |
|---|---|---|---|
| Standardized extract (capsules/tablets) | Standardized to 40-60% total saponins, minimum 6% protodioscin | 250-750 mg daily | Most common form in clinical trials and commercial products |
| Crude fruit powder | Dried, ground fruit | 2-5 g daily | Traditional Ayurvedic preparation |
| Decoction (Ayurvedic) | Gokshura kwatha | Varies by formulation | Traditional water decoction of fruits |
| Tincture (1:5) | Hydroethanolic extract | 2-5 mL, 2-3 times daily | Less common; standardization varies |
Clinical Trial Doses
- Kamenov et al. 2017: 750 mg/day of standardized extract for 12 weeks
- GamalEl Din et al. 2019: 750 mg/day for 3 months
- Typical range: 250-750 mg/day standardized extract for 4-12 weeks
Duration
- Clinical trials have typically lasted 4-12 weeks
- Long-term use beyond 12 weeks has very limited safety data
- Cycling use (e.g., 8 weeks on, 4 weeks off) is sometimes recommended by practitioners but is not evidence-based
Sources
- Fernandez-Lazaro D, et al. Effects of Tribulus (Tribulus terrestris L.) supplementation on erectile dysfunction and testosterone levels in men — a systematic review of clinical trials. Nutrients. 2025;17(7):1275
- Neychev V, Mitev V. The aphrodisiac herb Tribulus terrestris does not influence the androgen production in young men. J Ethnopharmacol. 2005;101(1-3):319-323
- Rogerson S, et al. The effect of five weeks of Tribulus terrestris supplementation on muscle strength and body composition during preseason training in elite rugby league players. J Strength Cond Res. 2007;21(2):348-353
- Kamenov Z, et al. Evaluation of the efficacy and safety of Tribulus terrestris in male sexual dysfunction — a prospective, randomized, double-blind, placebo-controlled clinical trial. Maturitas. 2017;99:20-26
- GamalEl Din SF, et al. Tribulus terrestris versus placebo in the treatment of erectile dysfunction and lower urinary tract symptoms in patients with late-onset hypogonadism. Aging Male. 2019;22(4):230-238
- Qureshi A, et al. A systematic review on the herbal extract Tribulus terrestris and the roots of its putative aphrodisiac and performance enhancing effect. J Diet Suppl. 2014;11(1):64-79
- De Souza KZ, et al. Tribulus terrestris for female sexual dysfunction: a systematic review. Climacteric. 2020;23(4):333-339
- Semerdjieva IB, Zheljazkov VD. Chemical constituents, biological properties, and uses of Tribulus terrestris: a review. Nat Prod Commun. 2019;14(8):1-26
Connections
- Compare with Maca for sexual function and libido support; maca has somewhat stronger clinical evidence and does not claim testosterone-boosting effects
- Compare with Tongkat Ali (Eurycoma longifolia) as another herb marketed for male sexual health; tongkat ali has some evidence for testosterone effects in hypogonadal men, unlike tribulus
- Related to Ashwagandha as a traditional Ayurvedic tonic with evidence for reproductive health; ashwagandha has stronger clinical evidence overall and is better characterized pharmacologically
- Compare with Fenugreek for male reproductive health claims; fenugreek has Commission E approval for other indications and some evidence for testosterone modulation via different mechanisms
- The steroidal saponin chemistry of tribulus is pharmacologically related to saponins in Fenugreek, though the clinical effects differ
Related Herbs
Ashwagandha
Withania somnifera
Ashwagandha (Withania somnifera) is a premier Ayurvedic adaptogen whose principal bioactive constituents -- withanolides (withaferin A, withanolide D, and withanolide glycosides) -- modulate the HPA axis, reduce cortisol, and exert GABA-mimetic activity. Two major standardized extracts, KSM-66 and Sensoril, have been evaluated in multiple double-blind RCTs demonstrating significant reductions in perceived stress and anxiety (Chandrasekhar et al. 2012, Salve et al. 2019), improved sleep quality, and modest testosterone-enhancing effects in men. Systematic reviews and meta-analyses (Pratte et al. 2014, Bonilla et al. 2021) confirm a consistent anxiolytic signal, though effect sizes vary by preparation and population. Ashwagandha falls entirely outside the European phytotherapy regulatory framework and carries notable drug interaction potential with thyroid hormones, immunosuppressants, and sedatives.
Fenugreek
Trigonella foenum-graecum
Fenugreek seed is one of the oldest medicinal plants, approved by Commission E for internal use (loss of appetite) and external use (local inflammation as poultice). The ESCOP monograph additionally includes adjuvant therapy in diabetes and mild hypercholesterolemia. The EMA/HMPC recognizes traditional use for appetite loss (internal) and mild skin inflammations (external). Clinical evidence for blood glucose reduction in type 2 diabetes is positive in meta-analyses (significant reductions in fasting glucose and HbA1c) but based largely on low-quality trials. A distinctive maple-syrup odor in sweat and urine is a harmless but notable side effect.
Maca
Lepidium meyenii
Maca (Lepidium meyenii) is a Peruvian Andean root vegetable cultivated above 4000m altitude, traditionally used for energy, stamina, and fertility. Clinical trials -- most notably Gonzales et al. (2002) -- demonstrate improved sexual desire and libido in both men and women, with some evidence supporting enhanced spermatogenesis. Uniquely, maca does not directly alter sex hormone levels (testosterone, estradiol, FSH, LH), suggesting a non-hormonal mechanism of action possibly involving the endocannabinoid system. It has also been studied for menopausal symptoms, exercise performance, and SSRI-induced sexual dysfunction. Maca falls outside the European phytotherapy regulatory framework but holds EU novel food status.