MastEnan (Drostanolone Enanthate 200mg/ml) is an injectable anabolic-androgenic steroid (AAS) derived from dihydrotestosterone (DHT). Historically, its base compound, drostanolone, was developed for clinical use to treat advanced, inoperable breast cancer in women. However, in modern contexts, Drostanolone Enanthate is not approved for human medical use in most countries and is primarily used off-label or illicitly within the bodybuilding and athletic communities.