Get Your Personalized Supplement StackSupplement Stack Quiz

Bulgarian Tribulus

Also known as: Bulgarian Tribulus, puncture vine, Tribulus terrestris L.

Overview

Tribulus terrestris, commonly known as Bulgarian Tribulus or puncture vine, is a flowering plant traditionally used in herbal medicine, particularly in regions like Bulgaria. Extracts from plants grown in Bulgaria are often referred to as 'Bulgarian Tribulus' and are typically standardized for their saponin content. This herbal supplement is widely marketed for its purported ability to enhance male sexual function, increase testosterone levels, and improve athletic performance. While research on Tribulus terrestris is moderate, with several clinical trials and systematic reviews available, findings are often mixed and sometimes contradictory. High-quality evidence, such as systematic reviews and randomized controlled trials (RCTs), provides the most reliable insights, though variations in study design and extract standardization can complicate definitive conclusions.

Benefits

The primary evidence-based benefit of Tribulus terrestris supplementation is a modest improvement in erectile dysfunction symptoms. A recent systematic review (Vilar Neto et al., 2025) analyzing clinical trials concluded that while it may improve erectile function, it does not consistently increase serum testosterone levels in men. Effect sizes for erectile function improvement have been modest and inconsistent across studies, with some RCTs showing statistically significant benefits compared to placebo, while others did not. Some secondary effects include potential benefits in libido enhancement and mild improvements in sexual satisfaction, although these are less rigorously quantified. Most studies focus on men with mild to moderate erectile dysfunction or suboptimal testosterone; benefits in healthy young men or athletes are less clear. Improvements in sexual function are generally reported after 4 to 12 weeks of consistent supplementation.

How it works

The proposed mechanisms of action for Tribulus terrestris primarily involve its active constituents, saponins, particularly protodioscin. These compounds are thought to influence hormone regulation and vascular function. One key pathway suggested is the increase in nitric oxide synthesis, which can lead to improved blood flow, a crucial factor in erectile function. Additionally, saponins may modulate androgen receptors, potentially enhancing the body's response to existing hormones rather than directly increasing hormone levels. The oral bioavailability of these saponins can be variable, which is why standardized extracts are preferred to optimize the delivery of active compounds and ensure consistent effects within the body.

Side effects

Tribulus terrestris is generally well tolerated in clinical trials, with no serious adverse events commonly reported. The most common side effects, occurring in over 5% of users, include mild gastrointestinal discomfort and headache. Less common side effects, affecting 1-5% of individuals, may include insomnia and restlessness. Allergic reactions are rare, occurring in less than 1% of users. While no major drug interactions have been definitively documented, caution is advised when combining Tribulus terrestris with antihypertensive medications or hormone therapies due to potential additive effects. There is limited data regarding contraindications, but individuals with hormone-sensitive conditions should exercise caution. Insufficient data exists to recommend its use in women, children, or pregnant/nursing women, and therefore, it should be avoided in these special populations.

Dosage

Studies on Tribulus terrestris vary in dosage, but effective doses typically range from 250 to 1500 mg per day of standardized extract, often standardized to 40-60% saponins. An optimal dosage, based on randomized controlled trials showing benefit, appears to be approximately 750-1500 mg per day of standardized extract, taken consistently for 4 to 12 weeks. The maximum safe dose is not well established; higher doses have not demonstrated increased efficacy and may lead to a greater incidence of side effects. The supplement is usually administered once or twice daily, preferably with meals to improve tolerance and absorption. Standardized extracts are preferred over raw powder for consistency in active compound delivery. No specific cofactors are required to enhance its absorption or efficacy.

FAQs

Does Bulgarian Tribulus increase testosterone?

Current high-quality evidence indicates that Tribulus terrestris does not reliably increase serum testosterone levels in men.

Is it effective for erectile dysfunction?

Some evidence supports a modest improvement in erectile function, but results can be variable among individuals.

How long before effects appear?

Improvements, particularly in sexual function, typically become noticeable after 4 to 12 weeks of consistent use.

Is it safe long-term?

Long-term safety data for Tribulus terrestris are limited; however, short-term use appears to be generally safe and well-tolerated.

Research Sources

https://pmc.ncbi.nlm.nih.gov/articles/PMC11990417/ – This systematic review of randomized controlled trials (Vilar Neto et al., 2025) concluded that Tribulus terrestris supplementation may modestly improve erectile dysfunction symptoms. However, it found no consistent evidence that it increases serum testosterone levels in men. The study highlighted heterogeneity in extract types, doses, and populations across the included trials, suggesting the need for more standardized research.