Tribulus terrestris
Puncture vine, Tribestan
Forms: Extracts standardized to saponins (protodioscin) and whole-plant powder; a common 'test booster' ingredient.
A plant extract marketed as a testosterone booster. Human trials show no meaningful rise in testosterone, strength or muscle; low-quality evidence hints at a small libido effect.
Legal status: Sold freely as a supplement and registered as an herbal medicine in some countries; not prohibited by WADA, but test-booster blends carry contamination risk.
What it gives
What people use it for and what the sources report. Strength is a general category from the literature: mild, clear or strong.
Purpose
Used to boost testosterone, libido and strength. Trials in men and athletes found no effect on testosterone or performance; some small studies report better erectile function or sexual desire.
What people seek and what studies show
In a placebo-controlled trial in elite rugby players during heavy training, tribulus added no strength or lean mass. A recent meta-analysis of 8 trials in men with erectile dysfunction found better erectile-function scores than placebo, with no change in testosterone, though a 2025 review rated half of the studies in this field as low quality. Effects on erections or desire in healthy men are not established.
Effects
Evidence: Limited human data — some human studies, small or short
Sought effects by goal (as reported)
Possible side effects
Possible does not mean certain: whether they appear depends on dose, duration, individual response and monitoring. Below — what to watch for and how to notice it early.
4 possible side effects
level · how often it is reportedWhat the levels mean
Level: general category from the literature, not your personal risk
How often
- common
- reported often
- possible
- reported in some people
- rare
- reported occasionally
How to lower the risks
For 3 of 4 possible side effects there are specific ways to lower the chance: everyday measures, supplements and options a doctor may consider. For the rest — general advice. No measure removes a risk completely.
Products obtained without a prescription are often fake, mislabeled or non-sterile, and there is no way to check at home. For legal supplements, look for third-party testing (Informed Sport, NSF).
No alcohol, no other liver stressors, limit oral steroids and their combinations, check liver enzymes.
How each option helps (5)
- Avoiding alcohol and other liver stressors — Removes a major extra liver stressor during oral steroids and other hepatotoxic drugs.
- Regular blood tests — ALT, AST, GGT and bilirubin show liver strain before symptoms; heavy lifting alone raises AST/ALT for days, and GGT helps tell muscle from liver.
- Ademetionine (SAMe) — Used for intrahepatic cholestasis in some countries, but trials are small and of low quality; untested in steroid users. Stopping the oral steroid matters most.
- N-acetylcysteine (NAC) — Restores glutathione; proven in paracetamol poisoning and helped in early acute liver failure of other causes, but untested in steroid users.
- TUDCA (tauroursodeoxycholic acid) — Improves bile flow in cholestatic disease; in steroid cholestasis only case reports, with failures in severe cases. Stopping the oral steroid matters most.
Drink enough water, control blood pressure, avoid regular painkillers (NSAIDs).
How each option helps (3)
- Fluid & electrolyte management — Good hydration eases kidney stress from heavy training and heat; dehydration plus NSAIDs is a classic cause of acute kidney injury.
- Regular blood tests — Creatinine reads high in muscular people and with creatine; cystatin C and a urine test give a truer picture of the kidneys.
- Working with a doctor — Investigates protein in the urine or falling kidney function and can start treatment that slows kidney damage.
Low-level side effects
How each option helps (2)
- Working with a doctor — Assesses persistent vomiting or severe belly pain (possible pancreatitis or gallstones) and adjusts prescribed GLP-1 treatment when nausea persists.
- Pancreatin + dimeticone (Pankreoflat) — May ease heaviness and gas after meals; can cause nausea or diarrhea. Not for pork or cow's milk protein allergy (anaphylaxis reported) or early acute pancreatitis.
Check-ups and blood tests
Which tests and check-ups to do and when. This is a guide — agree the exact schedule with your doctor.
Which doctors can help
Get medical help at once if
- Yellow skin or eyes, dark urine, pale stools, intense itching, pain under the right ribs — see a doctor now; sudden severe abdominal pain with dizziness or fainting — call emergency services.
- Much less urine than usual, cola-colored urine, new swelling, flank pain — see a doctor now.
In an emergency, call your local emergency number.
For women
Small trials suggest improved sexual function in women, but certainty is very low; safety in pregnancy is not established, and contaminated 'test boosters' may contain steroids that can cause virilization.
Myth & fact
“Does tribulus raise testosterone?”
No. In a 2025 review, 8 of 10 human studies found no change; the other two found only small rises, in men with low testosterone (hypogonadism).
Combinations
No specific combination notes for this substance yet. The stack check still adds up side effects that several substances share.
Sources
Possible side effects by body system, combinations, how to lower the risks and which tests to do — free.
Open the stack check