Testosterone stearate

Testosterone stearate, also known as testosterone octadecanoate, testosterone 17β-stearate, and androst-4-en-17β-ol-3-one 17β-stearate, is an injected anabolic-androgenic steroid (AAS) and an androgen ester – specifically, the C17β stearate (octadecanoate) ester of testosterone – which was never marketed. It is a prodrug of testosterone and, when administered via intramuscular injection, is associated with a long-lasting depot effect and extended duration of action. Testosterone stearate may occur naturally in the body.
It has been said that with longer-chain esters of testosterone like testosterone stearate, the duration of action may be so protracted that the magnitude of effect with typical doses may be too low to be appreciable.