Category: hormone
Aliases: Andro, 4-androstenedione, 4-androstene-3,17-dione
Endogenous C19 steroid and the immediate precursor to testosterone (via 17β-HSD) and to estrone (via aromatase). Weak direct AR activity — its supplement effect depends on peripheral conversion to testosterone/estrogens. Former OTC "prohormone" (now controlled). Oral andro often raises estrogens as much as testosterone, so the anabolic payoff is small and the estrogenic / HDL-lowering effects are a real concern.