Letrozole is a powerful aromatase inhibitor primarily used to reduce estrogen levels in the body. It works by blocking the aromatase enzyme, which converts androgens into estrogen, making it effective in preventing estrogen-related side effects like gynecomastia, water retention, and fat gain. Letrozole is commonly used during anabolic steroid cycles and post-cycle therapy (PCT) to help maintain a proper hormonal balance. It is favored for its ability to suppress estrogen more effectively than other aromatase inhibitors, making it ideal for athletes and bodybuilders seeking to control estrogen during intense steroid use.