Androstanolone heptanoate is an esterified form of androstanolone (5α-dihydrotestosterone or DHT), a potent androgen hormone. It is used primarily in the treatment of androgen deficiency conditions such as male hypogonadism, where it helps restore physiological androgen levels, supporting the development of primary and secondary male sexual characteristics. In hormone replacement therapy for men with low androgen activity, it can improve libido, mood, energy levels, muscle mass, and bone density. The heptanoate ester enables sustained release of the active hormone following intramuscular injection, reducing dosing frequency. It has also been utilized to promote weight gain, appetite stimulation, and muscle preservation in patients with chronic illnesses or cachexia. Due to its strong androgenic properties, it is prescribed under strict medical supervision to mitigate potential side effects like prostate enlargement or hair loss.