Exemestane
Exemestane (Aromasin) is an aromatase inhibitor that functions by lowering oestrogen production in the body. This medication is typically utilised to manage specific hormonally responsive conditions as part of a therapeutic regimen. One formulation is listed.
Key points
- An aromatase inhibitor that binds irreversibly to block oestrogen production, unlike some inhibitors with reversible action.
- Used to treat hormonally responsive breast cancer by lowering circulating oestrogen levels.
- Sold under the brand Aromasin, with joint pain and fatigue reported as effects linked to falling oestrogen levels.
What is Exemestane?
Exemestane is a potent pharmaceutical agent classified as an aromatase inhibitor. It blocks the enzyme responsible for converting androgens into oestrogens, effectively reducing the levels of this hormone circulating in the body. This mechanism is essential in treating conditions that rely on oestrogen to progress. While the generic name is Exemestane, the originator brand is Aromasin.
What Exemestane is used for
This medication is primarily used as a therapy for Breast Cancer. It is categorized within Oncology Support treatments, where it is used to manage hormonal sensitivity. By effectively lowering oestrogen levels, it addresses the hormonal aspect of the condition, making it a critical component of many standardized care protocols.
How does Exemestane work?
Exemestane functions by binding to the aromatase enzyme, which is the key driver of oestrogen synthesis in postmenopausal women and other specific states. This irreversible binding prevents the enzyme from performing its function. Unlike other inhibitors that may be reversible, this specific binding ensures a sustained reduction of oestrogen levels, which can manage the progression of hormonally responsive issues.
Exemestane brands and forms
The brand range for this ingredient centers primarily on Aromasin. Patients choosing between the original brand and generic versions will find that the active compound remains consistent regardless of the label. This medication is available in Tablet form. These options are often found within PCT & Men’s Fitness catalogues, reflecting the diverse applications of hormonal regulation.
Safety overview for Exemestane
What to check before using this medicine
Ensure your health records have been reviewed by a professional to confirm that this medication is appropriate for your specific hormonal profile.
Possible reactions and tolerability
Common responses can include fatigue, joint pain, or mood changes. These effects are often linked to the reduction in oestrogen.
Interactions and health factors
Other medications, including those affecting liver function or supplements that adjust hormone levels, may alter how this compound performs in the body. Product labelling and verified clinical sources remain the correct references for specific contraindications, interactions and reactions.
Further reading
What is exemestane used for?
Exemestane is used mainly to treat hormonally responsive breast cancer by lowering oestrogen levels in the body. It belongs to a group of treatments called aromatase inhibitors.
How does exemestane work?
Exemestane binds irreversibly to the aromatase enzyme and blocks the conversion of androgens into oestrogens. This reduces the level of oestrogen circulating in the body, which helps manage hormonally responsive conditions.
How long does exemestane take to work?
Exemestane usually takes 2 to 3 days to show its effect.
What are the side effects of exemestane?
Common reactions include hot flushes, fatigue and nausea, and joint pain or mood changes may also occur as oestrogen levels fall. Less common effects include insomnia, arthralgia and alopecia, while osteoporosis, pathological fractures and severe hepatitis are serious and need immediate medical attention. Speak to a doctor or pharmacist if you are concerned about any reaction.
Can exemestane be taken with other medicines?
Other medicines may affect how exemestane works in the body, including those that affect liver function and supplements that adjust hormone levels. Oestrogen containing therapies and St John's wort are listed as interactions. A doctor or pharmacist can advise on your other medicines.
Who should not take exemestane?
Exemestane is not suitable for people who are pre-menopausal, who have a hypersensitivity to exemestane, or who have severe kidney or severe liver impairment. Your health records should be reviewed by a professional to confirm whether this medicine suits your hormonal profile.
In which products can I find exemestane?
Products containing exemestane include Aromasin. Compare forms, strengths and packs in the listings above.
Is exemestane available over the counter in Thailand?
Yes, online. Yasabai does not ask for a prescription to order exemestane. We are an online store, not a dispensing pharmacy; we arrange your order and delivery on your behalf.
Ordering without a prescription →Can I order exemestane online in Thailand?
Yes. Our pharmacy partners ship from India to Thailand and across Asia in discreet packaging. Standard Airmail takes up to 3 weeks; Express Tracked Courier takes up to 1 week.
How ordering works →Related articles

23 Sept 2026 ⋅ 5 min read
Hormone Therapy for Breast Cancer: What the Tablets Do
A treatment measured in years, taken by people who move countries partway through it. Why the two families work differently, why joint pain is the effect that ends treatment early, and the bone change that gives you nothing to feel.
Read guide