Can Tribulus Cause Gyno?
By James Collier BSc (Hons) RNutr, MuscleTalk Moderator and Nutrition Consultant

Gynecomastia (or 'gyno' as it's informally referred to) is the development of small amounts of breast tissue in males and can be unsightly, itchy and in some cases painful. It is more commonly associated with the abuse of anabolic steroids in sports.
Tribulus terrestris is a completely natural plant product marketed in the supplement industry as a testosterone booster, hence is very popular in bodybuilding. Its effectiveness is debatable, but there is some evidence that it does increase testosterone levels, which obviously means that it can lead to a hormonal imbalance in the user. Therefore, in theory, it could lead to mild gyno. There has been no formal research on this though, but I did find one published case study by Jameel et al (2004). Here a male bodybuilder in his early twenties had been taking tribulus to help his gains and he developed gyno. However the subject did have history of gyno as an adolescent, which is very common in boys, and had been resolved.
Tribulus is a very popular supplement and this is the only published case study I could find, however it does mean that we can infer that in a susceptible individual, tribulus may worsen or possibly cause gyno.
If you are new to using tribulus, and have started to have a bit of itchiness around the nipples where you previously had none, I would stop it and refrain from using it or other testosterone boosters again. However tribulus is far from a 'must' supplement, so if you continue to train hard and consistently, follow a good diet with basic supplements, like whey, and get plenty of rest, and you'll continue to make great gains.

Reference: Jameel JK, et al (2004). Gynecomastia and the plant product 'tribulus terrestris'. Breast 13(5): 428-30.

Source: BB - The MuscleTalker ? Issue 53 (September 2006)

Let's discuss this issue... any opinions, experience?

I am considering its use in PCT. However, I have not researched it as much as I should. Does this product have a suppressing effect on the HPTA?

As for the dude who got gyno off of Trib.. I hate to see that guy on steroids(d-bol, test, etc) lol.

tribulus elevates lh > natural test...its safe...maybe a little acne for some but its very mild

I've never had any gyno while taking it.