Drostanolone propionate is a synthetic anabolic-androgenic steroid (AAS) derived from dihydrotestosterone (DHT). It is chemically known as 2α-methyl-17β-hydroxy-5α-androstan-3-one propionate. The compound is an ester prodrug of drostanolone, with the propionate ester at the 17β-hydroxy group enhancing its lipophilicity and prolonging its duration of action. Its primary and well-established application is in medicine, specifically as an active pharmaceutical ingredient (API) in oncology. It has been used as a palliative treatment for advanced, inoperable breast cancer in postmenopausal women, functioning as an anti-estrogen. Additionally, due to its potent anabolic properties, it has been investigated and used in the context of treating conditions like osteoporosis and muscle-wasting diseases, aligning with drugs for bone and joint disorders. Outside of strictly regulated medical use, it is also known for its misuse in sports and bodybuilding to enhance performance and muscle mass. Drostanolone propionate is typically administered via intramuscular injection. Its use is associated with androgenic side effects common to AAS and is a controlled substance in many jurisdictions.