Aromatase Inhibitors: Compound Reference
Aromatase inhibitors block the conversion of testosterone to estradiol. Used on cycle to manage estrogen-related side effects (gynecomastia, water retention) and during PCT. Over-suppression of estradiol carries its own risks: joint pain, lipid deterioration, and bone density loss.
Aromatase Inhibitors (3)
Anastrozole
Arimidex. Aromatase inhibitor. Blocks estrogen conversion.
Effects: Lowers estradiol, can worsen lipids (estrogen is cardioprotective), may reduce IGF-1, can cause joint pain and mood issues if estradiol crashes too low
Exemestane
Aromasin. Suicidal aromatase inhibitor. Irreversibly binds aromatase enzyme.
Effects: Lowers estradiol (suicidal inhibitor so no rebound), slightly less lipid impact than anastrozole, may have mild androgenic activity
Letrozole
Femara. Most potent aromatase inhibitor. Reduces estrogen by up to 98%. Used for extreme estrogen control or gyno reversal attempts.
Effects: Dramatically lowers estradiol (can crash E2), significantly worsens lipids (estrogen is cardioprotective), can cause joint pain, fatigue, and mood issues from suppressed E2, may reduce IGF-1, can lower bone mineral density with prolonged use
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