Estrogenic or antiandrogenic activities have been reported for other essential oils and some of their monoterpene constituents.13 - 18 On the basis of the three case reports and the in vitro studies, we suspect that repeated topical application of over-the-counter products containing lavender oil or tea tree oil was the cause of gynecomastia in the three patients. (nejm.org)
Note that anything that elicits symptoms of breast tenderness and fullness in women, is likely to also cause gynecomastia in men. (chestsculpting.com)
This condition is known as pseudogynecomastia and resembles another condition known as gynecomastia in which breast tissue starts developing. (pseudogynecomastia.org)