I was intrigued by a test booster patch by Ageforce. However, I noticed that it has as an ingredient androstenetrione (6-OXO). So I looked up on wiki and saw some disconcerting things.

1. 4-AT is a potent irreversible aromatase inhibitor that inhibits estrogen biosynthesis by permanently binding and inactivating aromatase in adipose and peripheral tissue.
2. In a FDA Warning Letter[citation needed] dated July 7, 2006, the U.S. Food and Drug Administration (FDA) argues that marketing of 4-AT violates the Federal Food, Drug, and Cosmetic Act and as such products containing it are adulterated by legal definition.

In 2008, Health Canada issued a warning that 4-AT had a health risk related to blood clotting and recommended all users immediately cease use.[9]

I also saw a reference to 6-oxo as a "suicidal estrogen inhibitor". What does that exactly mean? Is this permanently inactivating aromatase...all or some? Does the body make new aromtase to replace the inactivated ones at some point?

I don't know, this ingredient seems like serious stuff. Can anyone help clarify whether this is truly a concern? I remember hearing good things about "6-oxo" but then it got banned...so not sure how it can still be sold as a patch?

P.S. I'm not a body builder, more for low t & anti-aging purposes