Testosterone Cypionate Injection 250mg 10mL is a long-acting injectable testosterone formulation commonly prescribed for testosterone replacement therapy (TRT) in men with clinically diagnosed hypogonadism. Packaged in a 10 mL multidose vial at a concentration of 250 mg/mL, it provides sustained testosterone release following intramuscular administration. This guide explains its mechanism of action, dosage considerations, potential benefits, side effects, laboratory monitoring, and current clinical evidence to help readers better understand the appropriate medical use of testosterone cypionate.