Disclaimer
CompoundIQ publishes research summaries for informational and educational purposes only. Nothing on this site constitutes medical advice, diagnosis, or treatment recommendations. Always consult a licensed healthcare provider. Many compounds listed are research chemicals not approved for human use.
Exemestane
Also known as: Aromasin
Exemestane is a steroidal, irreversible (suicidal) aromatase inhibitor approved for breast cancer treatment. Unlike anastrozole and letrozole, it permanently inactivates the aromatase enzyme, requiring new enzyme synthesis for estrogen production to resume, and has a mildly androgenic structure.
Risk Level
Medium RiskDifficulty
Intermediate| CAS Number | 107868-30-4 |
| Molecular Formula | C20H24O2 |
| Class | Other |
| Category | SERMs & AIs |
Mechanism of Action
Exemestane is structurally similar to androstenedione and irreversibly binds to the aromatase enzyme active site, permanently inactivating it. New aromatase enzyme must be synthesized for estrogen production to resume, taking approximately 2-3 days. Its steroidal backbone gives it mild androgenic activity, and unlike non-steroidal AIs, it may have a less negative impact on lipid profiles and bone mineral density.
Dosing Research
Breast cancer: 25 mg/day orally after a meal (fat increases absorption by 40%). On-cycle estrogen management: 12.5-25 mg every other day or twice weekly. Half-life is approximately 24 hours, but effects persist longer due to irreversible enzyme inactivation. Should be taken with food for optimal absorption.
Side Effects & Risks
Hot flashes, fatigue, and joint pain are common. Potentially less impact on lipids and bone density compared to non-steroidal AIs due to androgenic properties. Hair thinning reported. Insomnia and headache possible. Estrogen rebound is less likely than with reversible AIs, but over-suppression is still possible with aggressive dosing.
Research Studies
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Disclaimer
CompoundIQ publishes research summaries for informational and educational purposes only. Nothing on this site constitutes medical advice, diagnosis, or treatment recommendations. Always consult a licensed healthcare provider. Many compounds listed are research chemicals not approved for human use.