Methenolone acetate is a synthetic anabolic-androgenic steroid (AAS) derived from dihydrotestosterone. It is the C1-methylated and 17β-acetylated derivative of methenolone. This structural modification enhances its oral bioavailability and metabolic stability compared to its parent compound. Primarily, methenolone acetate is used in human and veterinary medicine. In human medicine, it has been historically prescribed to treat conditions involving muscle wasting, such as those associated with chronic illnesses, severe burns, or prolonged corticosteroid therapy. It is also used to counteract osteoporosis and promote weight gain. In veterinary practice, it is employed as an anabolic agent to improve appetite, promote weight gain, and enhance physical condition in debilitated animals, particularly cats and dogs. As an anabolic steroid, it acts by binding to androgen receptors, stimulating protein synthesis and nitrogen retention in muscle tissue. Its use is strictly controlled due to potential side effects, including hepatotoxicity, androgenic effects, and its potential for abuse in sports. It is listed as a controlled substance in many countries.