Tribulus Terrestris
Summary
Tribulus is marketed to raise testosterone, but controlled trials in men found no change in total testosterone. Erectile-function scores improved more than with placebo in a 2026 meta-analysis and a 180-man trial (grade B). Small trials in women reported better sexual-function scores. No human drug-interaction studies were found.
Key facts
- Extracts of the leaves, fruit and roots of Tribulus terrestris, standardized to steroidal (furostanol) saponins such as protodioscin[1][4]
- No change: total testosterone did not differ from placebo in the 2026 meta-analysis or in young men given up to 20 mg/kg/day[3][2]
- Erectile function: IIEF-5 scores rose 3.23 points more than placebo across 8 studies (B)[3]
- 180 men with mild to moderate ED: IIEF improved 2.70 points more than placebo on 1,500 mg/day of extract for 12 weeks[4]
- A 2024 systematic review of testosterone boosters (4 tribulus studies) did not list tribulus among those that raised total testosterone[8]
- The plant injures the liver of grazing animals, but extracts have not been convincingly linked to liver injury in people at typical doses[1]
- 5 graded human outcomes on this page
- October 12, 2026
How it works
ProposedTribulus contains steroidal saponins, chiefly protodioscin. It was proposed to raise testosterone, but controlled trials in men found no change in testosterone, androstenedione or luteinizing hormone, so any effect on sexual function is not explained by higher total testosterone.[2][3]
What the human research says
Human trials only, one row per outcome. The form column shows what each trial actually tested. Grades follow our evidence-grading policy.
At a glance: strongest evidence per outcome
| Outcome | Grade | Effect | Strongest evidence | Rows |
|---|---|---|---|---|
| Sexual function | Grade B | Improved | RCT · n = 180 · 2017 | 4 rows |
| Testosterone | Grade D | No effect | RCT · n = 21 · 2005 | 1 row |
Every graded row
| Outcome | Effect | Grade | Best evidence | PMID |
|---|---|---|---|---|
| Erectile function (IIEF) in mild to moderate ED | Improved | Grade B | RCT · n = 180 · 2017 Men aged 18–65 with mild or moderate ED, including some with hypertension, diabetes or metabolic syndrome Form: Tribestan film-coated tablets (250 mg extract standardized to at least 112.5 mg furostanol saponins) · Dose: 2 tablets 3 times daily (1,500 mg/day of extract) · Duration: 12 weeks IIEF improved 2.70 points more than placebo (95% CI 1.40–4.01), with gains in desire and satisfaction. Adverse events were similar to placebo. | 28364864 (opens PubMed)Source [4] |
| Female sexual function (FSFI) | Improved | Grade C | RCT · n = 60 · 2014 Iranian women of reproductive age with hypoactive sexual desire disorder Form: Tribulus terrestris extract · Dose: 7.5 mg/day as reported in the abstract · Duration: 4 weeks Total FSFI and the desire, arousal, lubrication, satisfaction and pain domains improved more than with placebo; side effects were similar. | 24773615 (opens PubMed)Source [6] |
| Erectile function, testosterone and urinary symptoms in men with low testosterone | Improved | Grade D | RCT · n = 70 · 2019 Ageing men with partial androgen deficiency, ED and lower urinary tract symptoms Form: Tribulus terrestris · Dose: 3 times daily (amount not stated in the abstract) · Duration: 3 months Total testosterone and erectile-function scores rose in the tribulus group, but urinary symptom scores did not change. AST and PSA also rose slightly. The abstract reports within-group changes. | 30253697 (opens PubMed)Source [5] |
| Female sexual function in postmenopausal women | Improved | Grade D | RCT · n = 36 · 2016 Healthy sexually active postmenopausal women with low libido Form: Tribulus terrestris · Dose: 750 mg/day · Duration: 120 days Both groups improved on most FSFI domains; on a second questionnaire only the tribulus group improved desire, arousal, pain and orgasm. Free and bioavailable testosterone rose. | 27760089 (opens PubMed)Source [7] |
| Serum testosterone, androstenedione and LH | No effect | Grade D | RCT · n = 21 · 2005 Healthy men aged 20–36 Form: Tribulus terrestris extract · Dose: 10 or 20 mg/kg body weight per day in 3 doses · Duration: 4 weeks No difference from placebo in testosterone, androstenedione or luteinizing hormone at any of 5 time points. | 15994038 (opens PubMed)Source [2] |
Forms
| Form | Elemental % | Absorption (human data) | GI tolerance | Studied for |
|---|---|---|---|---|
| Standardized extract (furostanol saponins or protodioscin) | Varies[4] | No human absorption data in our sources.[1] | Adverse events similar to placebo over 12 weeks.[4][3] | Erectile function (1,500 mg/day of extract in the largest trial) |
| Whole-plant or fruit extract capsules | Varies[2][7] | No human absorption data in our sources.[1] | Not convincingly linked to liver injury in people at typical doses.[1] | Testosterone and libido claims; content of saponins varies |
Studied doses
Doses studied in human trials ranged from 7.5 mg/day (as reported in the abstract of a 4-week trial in women) to 1,500 mg/day of a standardized extract for 12 weeks in men, with 10–20 mg/kg/day used in a 4-week testosterone study.[2][4][6]
Interactions
Published interactions only: each row cites a source. No row means none was found in our sources, not that a combination is safe.
None found in our sources.
Who should be careful
- Expecting higher testosterone
- Controlled trials in men found no change in total testosterone versus placebo.[3][2]
- Prostate monitoring
- In one trial, PSA rose slightly after 3 months of tribulus.[5]
Talk to your pharmacist or clinician before starting a supplement, especially if you take prescription medicines.
Safety
Short trials looked well tolerated; long-term human safety and drug interactions are unstudied.
How to read the label
- Label dose vs clinical doseThe largest positive trial used 1,500 mg/day of an extract standardized to furostanol saponins. A women's trial reported 7.5 mg/day in its abstract and another used 750 mg/day, so doses are not comparable across products.[4][6][7]
- "Testosterone booster" claimsPooled placebo-controlled data show no change in total testosterone.[3][8]
- Check the saponin contentTrial products listed their furostanol saponin content; unstandardized products may differ.[4]
Frequently asked questions
Does tribulus raise testosterone?
Not in placebo comparisons. Total testosterone did not differ from placebo in the 2026 meta-analysis, and young men given up to 20 mg/kg/day saw no change. One small trial in older men with low testosterone reported a before-and-after rise.[3][2]
Does tribulus help erectile dysfunction?
In a 2026 meta-analysis of 8 studies, IIEF-5 scores rose about 3 points more than placebo; the largest trial (180 men) found a 2.7-point gain.[3][4]
Does tribulus help women's libido?
Small trials in pre- and postmenopausal women reported better sexual-function scores than placebo over 4 weeks to 4 months.[6][7]
Does tribulus interact with medicines?
No human drug-interaction studies were found for this page, so interactions are unknown rather than ruled out.
Sources
- [1]Tribulus. LiverTox: Clinical and Research Information on Drug-Induced Liver Injury.. NIDDK, 2022. database
- [2]The aphrodisiac herb Tribulus terrestris does not influence the androgen production in young men.. J Ethnopharmacol, 2005. RCT
- [3]Tribulus terrestris for management of patients with erectile dysfunction: a systematic review and meta-analysis of randomized trials.. Int J Impot Res, 2026. meta-analysis
- [4]Evaluation of the efficacy and safety of Tribulus terrestris in male sexual dysfunction-A prospective, randomized, double-blind, placebo-controlled clinical trial.. Maturitas, 2017. RCT
- [5]Tribulus terrestris versus placebo in the treatment of erectile dysfunction and lower urinary tract symptoms in patients with late-onset hypogonadism: A placebo-controlled study.. Urologia, 2019. RCT
- [6]Tribulus terrestris for treatment of sexual dysfunction in women: randomized double-blind placebo - controlled study.. Daru, 2014. RCT
- [7]Efficacy of Tribulus terrestris for the treatment of hypoactive sexual desire disorder in postmenopausal women: a randomized, double-blinded, placebo-controlled trial.. Menopause, 2016. RCT
- [8]Do "testosterone boosters" really increase serum total testosterone? A systematic review.. Int J Impot Res, 2024. systematic-review
What changed
- First draft (rebuilt after a lost earlier draft). Every PMID checked against NCBI E-utilities esummary (title and year) and the cited abstracts read; no retraction or erratum flagged for any cited PMID. Null testosterone results stated plainly. The women's trial dose is given as reported in its abstract (7.5 mg/day). No human interaction studies were found. No product links.
- Independent adversarial review (PR #201): spot-checked the 2026 meta-analysis, the 180-man trial, the androgen study, the hypogonadism trial and both women's trials against PubMed abstracts. Testosterone FAQ now notes the one small before-and-after rise in men with low testosterone alongside the placebo-controlled null.