Substances and brands used for muscle gain. Anabolic steroids are lab‑made versions of testosterone, technically known as anabolic‑androgenic steroids (AAS). “Anabolic” describes their muscle‑building effects, while “androgenic” refers to their role as sex hormones.

Testosterone

The primary androgen, drives the development of male traits and occurs naturally at much higher levels in men than in women.

These medications are prescribed mainly for low testosterone (male hypogonadism), but healthcare providers also use them to support muscle growth in certain medical conditions, such as specific cancers or AIDS.

Some athletes and bodybuilders misuse anabolic steroids to boost performance or change their appearance. They are the most widely used appearance‑ and performance‑enhancing drugs, with an estimated 3 to 4 million people in the United States taking them without medical guidance.

Anabolic steroids are available in several forms

• Pills • Injections • Creams or gels • Skin patches • Implantable pellets