Anabolic steroids, also known more properly as anabolic-androgenic steroids, are steroidal androgens that include natural androgens like testosterone as well as synthetic androgens that are structurally related and have similar effects to testosterone.

anti-estrogens, also known as estrogen antagonists or estrogen blockers, are a class of drugs that prevent estrogens like estradiol from mediating their biological effects in the body. They act by blocking the estrogen receptor and/or inhibiting or suppressing estrogen production.