- Puncture vine
- Ba ji li
For Patients & Caregivers
Tribulus has not been shown to treat or prevent cancer in humans.
Tribulus is an herb that grows in the subtropical regions of eastern and western Asia, southern Europe, and Africa. It is used in traditional medicine for chest pain, heart problems, dizziness, skin and eye disorders, to expel kidney stones, and as a diuretic and tonic. Tribulus is also marketed as a dietary supplement to improve sexual function and for body building due to the belief that it acts like testosterone in the body. However, this effect has not been confirmed. There are two small studies that suggest that it may help female sexual dysfunction, but large-scale studies are needed.
Test tube and animal studies show that tribulus has medicinal effects against high blood pressure, diabetes, inflammation, infection, and cancer.
The use of tribulus has been linked to adverse effects in both animals and humans. Due to its potential hormonal activities, prostate cancer patients should avoid this herb until more is known about its safety.
- To treat cancer
Tribulus showed anticancer activities in lab studies. It has not been tested in humans as a cancer treatment.
- To lower blood pressure
Tribulus extract can relax blood vessels and may help to lower blood pressure.
- To enhance sexual function
Tribulus increases sperm production in animal models, but human studies of its effects on testosterone levels gave mixed results. The current evidence suggests that it is not effective for increasing testosterone levels or treating erectile dysfunction. However, two small studies suggest that it may help female sexual dysfunction. Large-scale studies are needed to confirm this.
- To improve muscle strength and muscle mass
A clinical study did not find any significant changes in muscle strength or mass with use of tribulus.
- To treat infections
Tribulus has antifungal activities in lab studies. Human data are lacking.
- To reduce pain
Tribulus extract reduced inflammation in lab studies, but human studies have not been done.
- To treat kidney stones
Tribulus can promote urination and stop calcium compounds that cause kidney stones from forming. However, these effects have not been studied in humans.
- You are taking diruetics: Tribulus may increase the effects of diuretic drugs.
- You are taking antihypertensive drugs: Tribulus may have an additional blood pressure lowering effect.
- You are taking antidiabetics: Tribulus may have additive blood sugar lowering effects.
- You are taking clopidogrel: Tribulus may increase the risk of blood clots.
For Healthcare Professionals
Tribulus is a perennial herb that grows in the subtropical regions of eastern and western Asia, southern Europe, and Africa. It is used in traditional Chinese and Indian medicine systems for chest pain, heart-related problems, dizziness, skin and eye disorders, to expel kidney stones, and as a diuretic and tonic. It is also marketed as a dietary supplement to enhance sexual function (25) and for body building (26) (27).
Preliminary studies indicate that tribulus has analgesic (1), antihypertensive (2) (3), anti-inflammatory (4) (28), antiedematous (28), antioxidant (5) (6), diuretic (7), hypoglycemic (8), antibacterial (9), antifungal (9) (10), cardioprotective (29), and anticancer properties (11) (12) (15).
In vitro studies found that saponins in tribulus inhibit platelet aggregation (30). In animal models of chronic mild stress tribulus saponins produced antidepressive effects (31). In diabetic neuropathic pain models, a standardized tribulus extract was found to be comparable to the drug Pregabalin, with significant increases in pain threshold responses (32).
Tribulus has been shown to increase sperm production (13), but its effects on testosterone levels are mixed (14) (16). In human studies, testosterone increases only occurred when tribulus was part of a combined supplement therapy, making it difficult to determine its contribution to this effect (25). In a randomized double-blind study to evaluate effects on erectile dysfunction and serum total testosterone, tribulus was not more effective than placebo (33). A pilot study evaluating tribulus in men with partial androgen deficiency showed significant differences in testosterone levels and erectile function, but no significant differences in levels of luteinizing hormone (34). In women, however, two small studies indicate improvements in sexual dysfunction (35) (36). Larger randomized controlled trials are needed to confirm these results. A tribulus extract used alone did not not improve androgenic status or physical performance among athletes (26) (37).
Saponins in tribulus have shown activity against in breast (38) and prostate cancer cells (39), and may protect against UVB-induced carcinogenesis (40). In animal models, tribulus resulted in a significant reduction in tumor incidence, tumor burden, and cumulative number of papillomas (19), and relieved cisplatin-induced renal toxicity (41).
Due to its purported hormonal activities, prostate cancer patients should avoid this product.
In vitro, cinnamic amides in tribulus fruits inhibit papain-like protease (PLpro), an essential proteolytic enzyme which plays a critical role in virus-mediated RNA replication (42). Di-p-coumaroylquinic acid derivatives in tribulus are associated with its antioxidant effects (43).
Aphrodisiac effects may be associated with the constituent protodioscin, which leads to an increase in some sex hormones (44). Erectogenic effects may also occur via conversion of protodioscin to DHEA (36) or by concentration-dependent relaxation of the corpus cavernosum (CC) via reactions in the nitric oxide (NO)/NO synthase pathway and CC endothelium (45) (25). The NO release effect may explain observed physiological responses to tribulus supplementation, independent of testosterone level (25). In a study conducted in rats with ovarian cysts, tribulus extract showed a luteinizing effect related to gonadotropin-like activity (20).
Saponins exhibit cytotoxic and antihyperlipidemic effects (42). They may protect against atherosclerosis by suppressing angiotensin II-induced vascular smooth muscle cell proliferation via inhibition of intracellular ROS production, calcium ion mobilization, pkc-α expression, ERK1/2 phosphorylation, and proto-oncogene expression (46). In ischemic cells, polyphenol-mediated antioxidant activity with tribulus extract resulted in significant suppression of LDH release, ROS generation, and superoxide production (29).
In animal models, tribulus exerts a protective effect in diabetic rats by inhibiting oxidative stress (6) and lowering levels of glycosylated hemoglobin and cholesterols (8). In diabetic neuropathic pain models, tribulus modulates oxidative stress and inflammatory cytokine release in a dose-dependent manner via increases in superoxide dismutase, catalase, glutathione peroxidase, and reduced glutathione and lipid peroxide levels (32). In chronic mild stress models, the attenuation of serum corticotropin-releasing factor and cortisol levels by tribulus saponins suggest normalization of hypothalamic-pituitary-adrenal (HPA) axis hyperactivity (31). Antihypertensive effects occur via arterial smooth muscle relaxation, NO release, and membrane hyperpolarization (3). An aqueous extract also demonstrated angiotensin converting enzyme (ACE)-inhibition activity (2) that may help lower blood pressure. Phenolic acids such as chlorogenic acid, caffeic acid and 4-hydroxybenzoic acid may be responsible for reputed cardioprotective properties (29).
Tribulus extracts induce apoptosis and suppress cancer cell proliferation by activating caspase 3, dephosphorylating extracellular signal-related kinase (ERK) 1 and 2 (15), and by inhibiting nuclear factor (NF-kappa B) signaling (12). Saponins from tribulus inhibit multiple-drug resistance of cancer cells (11). In breast carcinoma cell lines, a saponin extract changed mRNA levels of CXCR4, CCR7 and BCL2 genes (38). In models of human prostate cancer, antitumor and antiangiogenic activities are attributed to cell-cycle arrest and apoptotic induction not involving the caspase pathway (39). Saponins also act as a modulator of apoptosis: in normal human keratinocytes, saponins attenuate UVB-induced programmed cell death through inhibition of intrinsic apoptotic pathway, but enhance apoptotic response in squamous cell carcinomas (40). The photoprotective effect of saponins is attributed to enhanced NER gene expression and inhibition of UVB-mediated NF-kappaB activation (40). In animal models, a hydroalcoholic extract of tribulus relieved cisplatin-induced renal toxicity, perhaps via diuretic effects that increase drug excretion, scavenging free radicals via increase in antioxidant enzymes, suppressing inflammatory agents, and acting on organic cation transporter 2 (OCT2) proteins (41).
Consumption of tribulus causes motor neuron adverse effects in animals by affecting the gamma-aminobutyric acid (GABA) receptors (18). The steroidal saponin diosgenin is thought to be responsible for hepatotoxic effects associated with tribulus (27).
Transient GI problems including irritation of gastric mucosa and gastric reflux (36).
- Severe hyperbilirubinemia: In a healthy 30-year-old male body-builder, followed by acute renal failure and bile-containing casts in the tubules associated with the ingestion of tribulus extract tablets, once daily for “a few months” (27).
- Neuro-, hepatic, and renal toxicity suggestive of acute tubular necrosis (ATN): In a 28-year-old man who consumed large quantities of tribulus extract for its antiurolithiatic properties. Additionally, he developed hypertension, seizures, and markedly elevated serum aminotransferases (>40x ULN) (17).
- Diruetics: Tribulus may increase the effects of other diuretic drugs (7).
- Antihypertensive drugs: Tribulus has angiotensin converting enzyme (ACE)-inhibition activity and therefore, may have an additional hypotensive effect (2) (3).
- Antidiabetics: Tribulus may have additive hypoglycemic effects (8).
- Clopidogrel: May increase the risk of blood clots. Stent thrombosis has been reported in patients following concurrent use of clopidogrel and an herbal formula containing tribulus (23).
- P-glycoprotein (P-gp) substrate drugs: In vitro, saponins and phenolic compounds from Tribulus terrestris has been shown to inhibit P-gp activity. This may increase the risks of adverse effect of substrate drugs (48).