Dosage for Aromasin: What You Need to Know

Key takeaways

• Aromasin (exemestane) is a prescription medication used to treat certain forms of breast cancer.
• It’s supplied as an oral tablet and is generally taken once daily after eating.

Aromasin is prescribed for adult women who have gone through menopause and previously received tamoxifen for their cancer. Specifically, it’s indicated for:

• adjuvant therapy for early estrogen-receptor–positive breast cancer (adjuvant therapy is given after the initial treatment to help reduce the chance the cancer will return)
• management of advanced breast cancer

This article outlines Aromasin’s dosing, available strength, and instructions for use.

Note: Use of binary labels such as “male” and “female” or “men” and “women” in this article mirrors the terminology used in the source material. Unless stated otherwise, it is unclear whether the research cited included people with broader gender identities.

Aromasin’s dosage

Below you’ll find information about Aromasin’s formulation, strength, and typical dosing recommendations.

What form does Aromasin come in?

Aromasin is provided as an oral tablet.

What strengths are available for Aromasin?

Aromasin is available in a single strength: 25 milligrams (mg) per tablet.

What is the usual Aromasin dose?

The standard recommended dose of Aromasin is 25 mg once daily, taken after a meal.

This is the commonly suggested dose. However, always follow the dose your healthcare provider prescribes. They will choose the most appropriate dose for your situation.

Is Aromasin intended for long-term use?

Yes. Aromasin is commonly used as a long-term treatment. If you and your clinician determine that Aromasin is safe and beneficial for you, it is likely to be continued for an extended period.

Dosage modifications

In certain situations, your clinician might need to adjust your Aromasin dose. For example, if you are taking medications that reduce Aromasin levels, your doctor may recommend increasing the dose to 50 mg once daily (or as advised).

Examples of drugs that can decrease Aromasin concentrations include:

• rifampicin (Rifampin)
• phenytoin (Dilantin)
• phenobarbital
• carbamazepine (Tegretol, others)

Frequently asked questions about Aromasin dosage

Here are answers to common questions about dosing Aromasin.

Is there an approved Aromasin dose for bodybuilding cycles?

No. There is no approved dosing regimen for bodybuilding. Aromasin is not authorized for uses other than treating early and advanced breast cancer.

Aromasin contains exemestane, a steroidal aromatase inhibitor. It works by attaching to aromatase, the enzyme that converts testosterone (the primary male sex hormone) into estrogen  (the primary female sex hormone). Blocking this conversion can raise testosterone levels, producing effects similar to testosterone replacement therapy (TRT).

Using Aromasin for bodybuilding is considered drug misuse (taking a medication in a way other than prescribed). Additionally, the World Anti-Doping Agency includes Aromasin on its prohibited list for all sports, including bodybuilding.

Note: Use of binary labels such as “male” and “female” or “men” and “women” in this article reflects the language of our sources. Unless noted, it’s unclear whether the referenced studies included participants with expansive gender identities.

How do Aromasin and Arimidex dosing compare?

Like Aromasin, Arimidex is used to treat certain early and advanced breast cancers. However, their dosing differs.

The typical dose for Aromasin is one 25-milligram tablet taken once daily after a meal. Arimidex’s usual dose is one 1-mg tablet taken once daily, with or without food.

To read more about Arimidex dosing, see the linked article.

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How to take Aromasin

Aromasin is an oral tablet taken once daily. It should be taken with food, ideally after a meal. Taking Aromasin after the same meal each day (for example, after breakfast) can help make it a regular habit.

What if I miss a dose?

If you miss a dose of Aromasin, contact your healthcare provider as soon as possible. They may advise you to take the missed dose if it’s close to your usual dosing time, or they may instruct you to skip it and take your next dose at the regular time the following day.

Do not take two doses to compensate for a missed one, as this can increase the risk of adverse effects.

If you struggle to remember doses, consider using a medication reminder—set an alarm, use a reminder app, or program a timer on your phone. A simple kitchen timer can also help.

What to do in case of an Aromasin overdose

Do not take more Aromasin than prescribed. Exceeding the recommended dose can cause serious adverse effects.

What to do if you take too much Aromasin

Contact your doctor immediately if you suspect an overdose. You can also call 800-222-1222 to reach America’s Poison Centers or use its online resource. If you experience severe symptoms, call911 (or your local emergency number) right away or go to the nearest emergency department.

Ask a pharmacist

Q:

I understand that prior tamoxifen use is required before starting Aromasin. Does the tamoxifen dose I took previously impact my new Aromasin dose?

A:

Generally, no. The typical recommended Aromasin dose is 25 mg taken once daily after a meal, irrespective of your previous tamoxifen dose. However, your clinician will determine the most suitable dose for your circumstances.

If you have questions about your Aromasin dosing, discuss them with your doctor.

Disclaimer: HealthEH has endeavored to ensure the accuracy, completeness, and currency of the information presented. However, this article is not a substitute for the expertise of a licensed healthcare professional. Always consult your doctor or another qualified health provider before starting any medication. The drug information here may change and does not cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other details does not imply that a drug or combination is safe, effective, or appropriate for every patient or situation.

Article resources

• Aromasin (exemestane) tablets, for oral use. (2024). https://www.accessdata.fda.gov/drugsatfda_docs/label/2024/020753s025lbl.pdf 
• Food and Drug Administration. (2025). Orange Book: Approved drug products with therapeutic equivalence evaluations. https://www.accessdata.fda.gov/scripts/cder/ob/index.cfm 
• World anti-doping code international standard prohibited list 2025. (2025). https://www.wada-ama.org/sites/default/files/2024-09/2025list_en_final_clean_12_september_2024.pdf