Aromatase inhibitor
What it means
An aromatase inhibitor is a medication that blocks the enzyme aromatase, which the body uses to make estrogen. It's mainly used in breast cancer treatment to lower estrogen levels.
Lowering estrogen this way can cause faster bone loss than natural menopause, so bone health needs active monitoring if you're on this medication.
Aromatase inhibitors work by blocking the conversion of other hormones into estrogen. They're used as a treatment for breast cancer because many breast cancers depend on estrogen to grow. By cutting estrogen production, the medication helps fight the cancer, but estrogen also plays a big role in protecting bone, so bone loss can speed up — often faster than what happens during natural menopause.
This isn't just a women's issue. In men, a similar enzyme process converts testosterone into oestradiol, which turns out to be the main hormone protecting male bone. If a man's oestradiol is strongly suppressed by an aromatase inhibitor, for example while being treated for low testosterone, his bones can suffer even if his testosterone numbers look fine. It's a reasonable question to bring to the prescriber if this applies to you.
Because the bone effects of aromatase inhibitor therapy are large and predictable, doctors recommend an explicit bone plan for people on it — things like baseline bone density testing, checking vitamin D and calcium levels, fracture-risk assessment, and loading or resistance exercise. Any decisions about starting, stopping, or adjusting this medication belong with your prescriber, who can weigh the cancer treatment benefits against the bone effects.
How sure is this?
Graded Strong Clinical Evidence: Supported by multiple well-designed clinical studies in humans. Read each study with its grade in mind. One study is a piece of the picture, not the whole of it.
Where the Academy teaches it
This page is the short version. The lessons teach it in full, with the context around it and a quiz to lock it in.
Questions people ask about this
Yes, it's possible — a number of common medications can affect bone, so it's a smart question to ask. This doesn't mean you should change anything on your own; it just means it's worth reviewing your full medication list with your prescriber to understand whether bone monitoring makes sense for you.
Read the full answer →Yes. Men absolutely can get osteoporosis — in fact, roughly a third of all hip fractures happen in men, and men who fracture a hip have higher mortality afterward than women do. The decline is more gradual than the sharp drop women experience at menopause, but it's real and often overlooked.
Read the full answer →Related words
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Education only, not medical advice. Decisions about tests, medications and treatment belong with your own doctor. OsteoStrong does not diagnose, treat or cure any disease.
