What are they?

Anti-Estrogens are prescription medications that are abused by steroid users to block or minimize the effects of estrogen in the body for purposes of countering the side effects of anabolic androgenic steroids. Anti-Estrogens act to either decrease the amount of estrogen in the body or block the estrogen receptors. In men, this will cause the natural testosterone levels to increase.

Examples of Anti-Estrogens include but are not limited to: hormone antagonists and modulators (i.e., mechano growth factors and corticotrophins), Aromatase Inhibitors (i.e., anastrozole, dianastrozole, and androsternetrione), Estrogen Modulators (i.e., tamoxifen) and Gonadotropins (i.e., clomiphene and human chorionic gonadotropin (“hCG”)).

What do Anti-Estrogens look like?

Most Anti-Estrogens are in tablet form. Some Gonadotropins, like hCG, are injectable.

How are Anti-Estrogens used?

Anti-Estrogens are often used after a cycle of anabolic androgenic steroids.

What are their short and long-term effects on the body?

Physical side effects associated with Anti-Estrogen use include: increased risk of blood clots, abdominal pain, joint pain, muscle pain, headaches, nausea, hot flashes, fatigue, high blood pressure, intestinal problems acne, bladder problems, rapid weight gain, injection site reactions, swelling due to increased fluid retention and difficulty breathing. Women may experience vaginal irregularities such as dryness or discharge. Men may experience abnormal growth of testes.
Psychological side effects associated with Anti-Estrogen use include: insomnia, depression, anxiety, lethargy, and mood swings.
A major concern with Anti-Estrogens has to do with the lowering of estrogen levels in the body. Decreased estrogen levels increase the risk of osteoporosis, which increases the risk of bone fractures. Reducing the amount of estrogen also has an effect on the body's blood lipid levels and might increase the risk of heart problems or cardiovascular disease.

What is their federal classification?

To be used legally, these substances require a legitimate prescription from a physician.

Source: Anti-Estrogens | Play Healthy