Exemestane (Exos)

Exos contains exemestane, a steroidal “suicidal” aromatase inhibitor. Unlike other AIs, it permanently deactivates the aromatase enzyme, which prevents estrogen rebound after stopping use.

Exemestane lowers estrogen by around 85% at standard doses and is gentler on cholesterol levels than non-steroidal AIs. It does not stress the liver and can be used safely for longer periods.

Exemestane also lowers SHBG, which increases free testosterone and improves cycle efficiency. It is widely used both during cycles and for post-cycle therapy.

Studies show exemestane can significantly increase total and free testosterone in a short time and raise IGF-1 levels. Because it permanently disables aromatase enzymes, estrogen levels remain stable even after dosing stops.