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25 mg - 25 tablets


Aromasin belongs to a category and class of drugs known as aromatase inhibitors (AIs). Aromatase inhibitors belong to an even broader class of drugs known as anti-estrogens. The other subcategory of drug under the anti-estrogens classification is the selective estrogen receptor modulators (SERMs), such as Nolvadex and Clomid. AIs and SERMs make up anti-estrogens. Aromatase inhibitors differ greatly from SERMs in their action and how they deal with the issues of estrogen control.

Aromasin is a very strong and very potent steroidal aromatase inhibitor of the suicidal type, and information within the packaging in prescription Aromasin describes the ability for Aromasin to reduce Estrogen levels by 85%, as evidenced by studies on breast cancer patients[1]. Suicidal aromatase inhibitors such as Aromasin (Exemestane) serve to permanently inhibit and disable the aromatase enzyme to which it is bound to[2]. This renders the enzyme inactive forever. The body will eventually manufacture more aromatase enzymes, but the currently bound enzymes are bound indefinitely, eliminating any risk for Estrogen rebound. This is unseen with the other two major aromatase inhibitors (Arimidex and Letrozole), which are non-suicidal aromatase inhibitors that are only bound to the aromatase enzyme for limited time periods before the aromatase inhibitors unbind and become metabolized. If a non-suicidal aromatase inhibitor is halted too abruptly, the circulating inhibited aromatase enzymes that have not been metabolized out of the body will then become free again, and begin aromatizing androgens into Estrogens at an often rapid rate. This is not the case with Aromasin.

Aromasin Properties and Actions:

Aromasin is a steroidal suicidal aromatase inhibitor. This means that it possesses the characteristic four ring cycloalkane carbon structure common of all steroidal molecules. The fact that Exemestane is a steroidal  aromatase inhibitor is the prime reason as to why it is a suicidal aromatase inhibitor that remains permanently bound to the aromatase enzyme. As the aromatase enzyme is highly attracted to the steroidal structure of the androgens (Testosterone) it aromatizes into Estrogen, Aromasin’s chemical structure essentially ‘fools’ the aromatase enzyme into binding with it, only to become inhibited/deactivated. Because the binding strength is so great, this inhibition becomes permanent for the aromatase enzyme that Aromasin has become bound to. A similar steroidal aromatase inhibitor, Formestane, exhibits the exact same characteristics (although it is much weaker and less potent in comparison to Aromasin). This is why there is absolutely no risk of Estrogen rebound when Aromasin administration is abruptly halted.

Aromasin Side Effects:

Aromasin is known for being fairly tolerable throughout the majority of users. However, it is not without its potential side effects, and there are some of concern. They are usually as a result of a reduction in Estrogen levels that is too much, or too fast, or Estrogen suppression for too long. It’s also important to understand that the use of Aromasin (or any aromatase inhibitors) results in a greater side effect profile for women than for men.

The first Aromasin side effect that individuals tend to encounter is that of joint and/or bone pain. This is because Estrogen plays a significant and important role in maintaining proper mineralization and bone density within bone tissue. Although this is a characteristic of all aromatase inhibitors, Aromasin has been shown in studies to actually strengthen bone tissue (to a point), while AIs like Arimidex (Anastrozole) and Letrozole (Femara) have shown severe reductions in the same.

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