Despite these benefits, aromatase inhibitors can cause significant side effects, including accelerated bone loss leading toosteoporosis.
Aromatase inhibitors work by binding to aromatase and preventing aromatization from occurring.
Aromatase inhibitors differ from tamoxifen in that tamoxifen binds to estrogen receptors on cells rather than to aromatase.
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The different mechanisms of action achieve similar outcomes, but with different rates of efficacy.
An aromatase inhibitor may also be recommended in women who have advanced cancer that progresses while on tamoxifen.
Each individual aromatase inhibitor has its own specific indications.
Aromatase inhibitor treatment is started after primary treatment is complete.
This includesbreast cancer surgeryand possiblychemotherapy.
Treatment with aromatase inhibitors can be started at the same time withradiation therapy.
Dosage
Aromatase inhibitors are delivered in tablet form and prescribed as a once-daily dose.
Arimidex and Femara can be taken with or without food.
Aromasin should be taken after a meal as fat in food aids in the drug’s absorption.
Side Effects
As with any medication, aromatase inhibitors can cause side effects and adverse reactions.
Osteoporosis Risk
The long-term effects of aromatase inhibitors are arguably more concerning.
Treatment with tamoxifen for two to five years before aromatase inhibitors may slow down the rate of bone loss.
Interactions
Aromatase inhibitors can interact with certain medications.
Ongoing Research
There is growing evidence that aromatase may benefit more than just postmenopausal women.
U.S. National Library of Medicine.
MedlinePlus.Hormone therapy for breast cancer.
Miller WR, Larionov AA.Understanding the mechanisms of aromatase inhibitor resistance.Breast Cancer Res.
ARIMIDEX.Highlights of prescribing information.
Aromasin.Highlights of prescribing information.
Femara.Highlights of prescribing information.
2017;377:1836-1846. doi:10.1056/NEJMoa1701830
U.S. Food and Drug Administration.Highlights of prescribing information: Arimidex (anastrozole).
U.S. Food and Drug Administration.Highlights of Prescribing Information: Femara (letrozole).
U.S. Food and Drug Administration.Highlights of prescribing information: Aromasin (exemestane).
