Background

Tribulus (Tribulus terrestris) is a plant that produces fruit covered with spines. It is traditionally known as an aphrodisiac in various cultures.

Tribulus has chemicals that might increase levels of some hormones. But it doesn't appear to increase male hormones (testosterone) in humans. Tribulus is also known as puncture vine because its sharp spines can flatten bicycle tires.

People use tribulus for sexual disorders, infertility, chest pain, enlarged prostate, and many other conditions, but there is no good scientific evidence to support most of these uses.

Safety Safety definitions

When taken by mouth: Tribulus is possibly safe for most people when taken at doses of 750-1500 mg daily for up to 90 days. Side effects are usually mild and uncommon, but might include stomach pain, cramping, and diarrhea. There isn't enough reliable information available to know if tribulus is safe to use for longer than 90 days or what the side effects might be.

Eating the spine-covered fruit of tribulus is likely unsafe. There have been reports of serious lung problems due to eating the fruit.

Special Precautions & Warnings:

Pregnancy: Taking tribulus during pregnancy is possibly unsafe. Animal research suggests that tribulus might harm development of the fetus.

Breast-feeding. There isn't enough reliable information to know if tribulus is safe to use when breast-feeding. Stay on the safe side and avoid use.

Surgery: Tribulus might affect blood sugar levels and blood pressure. This might interfere with blood sugar and blood pressure control during and after surgery. Stop using tribulus at least 2 weeks before a scheduled surgery.

Effectiveness

Dosing & administration

Tribulus has most often been used by adults in doses of 750-1200 mg by mouth daily for 12 weeks. Speak with a healthcare provider to find out what dose might be best for a specific condition.

Interactions with pharmaceuticals

Lithium

Interaction Rating=Moderate Be cautious with this combination.

Tribulus might have an effect like a "water pill" or diuretic. Taking tribulus might decrease how well the body gets rid of lithium. This could increase how much lithium is in the body and result in serious side effects. Talk with your healthcare provider before using this product if you are taking lithium. Your lithium dose might need to be changed.

Medications for diabetes (Antidiabetes drugs)

Interaction Rating=Moderate Be cautious with this combination.

Tribulus might lower blood sugar levels. Taking Tribulus along with diabetes medications might cause blood sugar to drop too low. Monitor your blood sugar closely.

Medications for high blood pressure (Antihypertensive drugs)

Interaction Rating=Moderate Be cautious with this combination.

Tribulus might lower blood pressure. Taking Tribulus along with medications that lower blood pressure might cause blood pressure to go too low. Monitor your blood pressure closely.

Interactions with herbs & supplements

Herbs and supplements that might lower blood pressure: Tribulus might lower blood pressure. Taking it with other supplements that have the same effect might cause blood pressure to drop too much. Examples of supplements with this effect include andrographis, casein peptides, L-arginine, niacin, and stinging nettle.
Herbs and supplements that might lower blood sugar: Tribulus might lower blood sugar. Taking it with other supplements with similar effects might lower blood sugar too much. Examples of supplements with this effect include aloe, bitter melon, cassia cinnamon, chromium, and prickly pear cactus.

Interactions with foods

There are no known interactions with foods.