Dosage for Aromasin: What You Need to Know

Aromasin (exemestane) is a prescription drug that’s used to treat certain types of breast cancer. The drug comes as a tablet that you swallow. It’s usually taken once per day after a meal.

Aromasin is used in adult females* who’ve gone through menopause and have received tamoxifen treatment in the past for their cancer. Specifically, it’s used for:

adjuvant treatment† of early breast cancer (for this use, the breast cancer must be estrogen-receptor positive)
treatment of advanced breast cancer

The active ingredient in Aromasin is exemestane. (An active ingredient is what makes a drug work.) Aromasin belongs to a group of drugs called aromatase inhibitors.

This article describes the dosage of Aromasin, as well as its strength, and how to take it. To learn more about Aromasin, see this in-depth article.

* In this article, we use the term “female” to refer to someone’s sex assigned at birth. For information about the difference between sex and gender, see this article.
† Adjuvant treatment is given after the original treatment, usually to lower the risk of the cancer returning.

Below are details about Aromasin’s form, strength, and typical dosages.

What is Aromasin’s form?

Aromasin comes as a tablet that is taken by mouth.

What strength does Aromasin come in?

Aromasin comes in only one strength: 25 milligrams (mg) per tablet.

What is the usual dosage of Aromasin?

The recommended dosage of Aromasin is 25 mg once per day, taken after a meal.

This dosage is commonly recommended. But be sure to take the dosage your doctor prescribes for you. They’ll determine the best dosage to fit your needs.

Is Aromasin used long term?

Yes, Aromasin is typically used as a long-term treatment. If you and your doctor determine that Aromasin is safe and effective for you, it’s likely that you’ll use it long term.

Dosage adjustments

In some cases, your doctor may need to increase your Aromasin dosage. Specifically, if you’re taking drugs that lower the Aromasin level in your body, you may need to take 50 mg of Aromasin once per day (or as recommended).

Examples of medications that can lower the level of Aromasin in your body include:

rifampicin (Rifampin)
phenytoin (Dilantin)
ketoconazole
erythromycin (Ery-Tab)

Below are answers to some common questions about Aromasin’s dosage.

Is there an approved Aromasin dosage that can be used on a cycle for bodybuilding?

No, there is no approved dosage for bodybuilding purposes. Aromasin is not approved for uses other than treating early and advanced breast cancer.

Aromasin contains the active ingredient exemestane, which is a steroid. Aromasin works by binding to aromatase, the enzyme in the body responsible for turning testosterone (the main sex hormone in males*) into estrogen (the main sex hormone in females*). This increases the level of testosterone in the body, which has similar effects to testosterone replacement therapy (TRT).

Taking Aromasin for bodybuilding purposes is considered misuse of the drug. (Misuse means taking a drug in a way other than how a doctor prescribes it.) Also, the World Anti-Doping Agency lists Aromasin as a banned substance for any sport, including bodybuilding.

How do the dosages for Aromasin and Arimidex compare?

Similar to Aromasin, Arimidex is used to treat certain types of early and advanced breast cancer. But the dosages for these drugs are different.

The recommended dosage for Aromasin is one 25-milligram (mg) tablet taken once per day after a meal. The recommended dosage for Arimidex is one 1-mg tablet taken once per day, with or without food.

To learn more about Arimidex’s dosage, see this article.

If you forget to take a dose of Aromasin, call your doctor’s office as soon as possible. Your doctor may want you to take the dose if it’s close to the time you usually take it. Or they may have you wait to take the next dose at your usual time the next day.

Don’t take two doses to make up for the missed dose. Doing so can raise your risk for side effects from the drug.

If you need help remembering to take your dose of Aromasin on time, try using a medication reminder. This can include setting an alarm, downloading a reminder app, or setting a timer on your phone. A kitchen timer can work, too.

The dosage of Aromasin you’re prescribed may depend on several factors. These include:

other medications you may be taking (see “Dosage adjustments” under “What is Aromasin’s dosage?”)
other conditions you may have

Aromasin comes as a tablet that’s taken once a day by mouth. It should be taken with food, preferably after a meal. It might be helpful to take Aromasin after the same meal each day (such as every day after breakfast) so it becomes part of your routine.

Some people may choose to take Aromasin off-label to increase testosterone for bodybuilding. But this is not an approved use for Aromasin, which means using it for this purpose may not be legal and is considered misuse of the drug. (Misuse means taking a drug in a way other than how a doctor prescribes it.)

Also, the World Anti-Doping Agency lists Aromasin as a banned substance for any sport, including bodybuilding.

Don’t use more Aromasin than your doctor prescribes. Using more than this can lead to serious side effects.

What to do in case you take too much Aromasin

Call your doctor right away if you think you’ve taken or used too much Aromasin. You can also call 800-222-1222 to reach America’s Poison Centers, or use its online resource. But if you have severe symptoms, call 911 (or your local emergency number) immediately or go to the nearest emergency room.

The sections above describe the typical dosage provided by the drug manufacturer. If your doctor recommends Aromasin for you, they’ll prescribe the dosage that’s right for you.

Remember, you shouldn’t change your dosage of Aromasin without your doctor’s approval. Only take Aromasin exactly as prescribed. Talk with your doctor if you have questions or concerns about your current dosage.

Here are some examples of questions you may want to ask your doctor:

Does my dosage of Aromasin need to be adjusted if I have certain conditions?
How will I know whether my current dose of Aromasin is working for me?
Does my dosage of Aromasin need to change if I’m taking other drugs along with it?

To learn more about Aromasin, see these articles:

All About Aromasin
Side Effects of Aromasin: What You Need to Know

To get information on different conditions and tips for improving your health, subscribe to any of Austra Health’s newsletters. You may also want to check out the online communities at Bezzy. It’s a place where people with certain conditions can find support and connect with others.

Q:

I know that to use Aromasin, I must have previously tried tamoxifen. So does my tamoxifen dose affect my new Aromasin dose?

A:

In general, no. The recommended dosage of Aromasin is 25 milligrams (mg) taken once per day after a meal, regardless of your past tamoxifen dose. But your doctor will determine the best dosage to fit your needs.

If you have questions about your Aromasin dosage, talk with your doctor.

The Austra Health Pharmacist Team Answers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.

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Disclaimer: Austra Health has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.

Last medically reviewed on March 3, 2023

How we reviewed this article:

Austra Health has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references. You can learn more about how we ensure our content is accurate and current by reading our editorial policy.

Arimidex. (2022).
astrazeneca.ca/content/dam/az-ca/downloads/productinformation/arimidex-product-monograph-en.pdf
Aromasin (exemestane) tablets, for oral use. (2021).
accessdata.fda.gov/drugsatfda_docs/label/2021/020753s022lbl.pdf
World anti-doping code international standard prohibited list 2021. (2021).
wada-ama.org/sites/default/files/resources/files/2021list_en.pdf

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