Testosterone undecanoate is an androgen and anabolic steroid (AAS) medication that is used mainly in the treatment of low testosterone levels in men.
In addition to its medical use, testosterone undecanoate may be used to improve physique and performance.
Along with testosterone enanthate, testosterone cypionate, and testosterone propionate, testosterone undecanoate is one of the most widely used testosterone esters.
However, it has advantages over other testosterone esters in that it can be taken by mouth.
Testosterone undecanoate is used in androgen replacement therapy. It is specifically approved only for the treatment of hypogonadism.