Arimidex (anastrozole) is a brand-name oral tablet prescribed for certain forms of breast cancer. Arimidex has interactions with some other drugs and certain supplements. Examples include estrogens and tamoxifen (Soltamox).

Arimidex is prescribed for treating certain forms of breast cancer in females who have gone through menopause.

An interaction occurs when one substance causes another substance to have a different effect than expected.

To learn more about the interactions of Arimidex, keep reading. For additional information, including details about its uses, see this article on Arimidex.

Note: Sex and gender exist on spectrums. Use of the term “female” in this article refers to sex assigned at birth.

Before you start treatment with Arimidex, tell your doctor and pharmacist which prescription, over-the-counter (OTC), and other medications you take. By sharing this information with them, you may help prevent possible interactions. (To learn whether Arimidex interacts with supplements, herbs, or vitamins, see the “Arimidex and other interactions” section.)

If you have questions about drug interactions that may affect you, ask your doctor or pharmacist.

Here’s a table of drugs that can interact with Arimidex. Keep in mind that this table doesn’t include all drugs that may interact with Arimidex. These interactions are described in detail in “Drug interactions in depth.”

Drug class or drug nameDrug examplesInteraction result with Arimidex
estrogen-containing treatments• birth control medications, such as pills, patches, and vaginal rings
• hormone replacement therapy (HRT)
• vaginal estrogen products, such as creams and tablets		can make Arimidex less effective
tamoxifen (Soltamox)—can make Arimidex less effective
prasterone (Intrarosa)—can make Arimidex less effective

In some cases, factors or conditions could prevent your doctor from prescribing Arimidex due to the risk of harm. These are known as contraindications. Arimidex contraindications include:

Having had an allergic reaction to Arimidex or any of its ingredients

If you’ve had an allergic reaction to Arimidex or any of its ingredients, your doctor will likely not prescribe Arimidex. Taking the drug could cause another allergic reaction. You can ask them about other treatments that may be better choices for you.

Note:Before you start treatment with Arimidex, it’s important to tell your doctor if this contraindication applies to you. They can determine whether to prescribe Arimidex.

There aren’t any known interactions between Arimidex and alcohol. However, your doctor may advise you to avoid or limit alcohol consumption during Arimidex treatment.

This is because drinking alcohol while taking the drug may worsen some Arimidex side effects or make them more likely to occur. For example, you may experience:

  • nausea
  • vomiting
  • headache
  • dizziness
  • tiredness

In addition, consuming large amounts of alcohol can cause liver damage. Arimidex may also rarely cause liver problems as a side effect. This means that drinking alcohol during Arimidex treatment may increase the risk of liver problems.

Note that alcohol is known to raise the riskTrusted Source of developing breast cancer. But if you’ve been diagnosed with breast cancer, it’s not known if drinking alcohol can worsen the cancer or affect your cancer treatment.

If you have questions about drinking alcohol while taking Arimidex, talk with your doctor.

Here’s a closer look at certain drug interactions of Arimidex.

Drugs that contain estrogen

Drugs that contain estrogen include HRTs. These are used to treat symptoms of menopause, such as hot flashes, joint pain, and night sweats. They’re also used to help prevent osteoporosis after menopause. Vaginal estrogen products are used to treat vaginal dryness related to menopause.

Other estrogen-containing drugs include certain forms of birth control, such as pills, patches, and vaginal rings.

Interaction result: Using drugs that contain estrogen with Arimidex can make Arimidex less effective at treating breast cancer.

Interaction explained: Arimidex works by lowering estrogen levels in your body. (Estrogen can encourage breast cancer to grow and spread.) Drugs that contain estrogen increase estrogen levels in your body. So they oppose the effect of Arimidex.

Examples of estrogen drugs: Here are some estrogen-containing drugs that may interact with Arimidex:

  • ethinylestradiol/levonorgestrel (Seasonale, Daysee, others)
  • ethinylestradiol/drospirenone (Yasmin, others)
  • estradiol (Climara, Divigel, Vagifem, others)
  • estradiol/norethindrone acetate (Combipatch, Activella, others)
  • estradiol/levonorgestrel (Climara Pro)

Steps you or your doctor may take: You should not use drugs that contain estrogen during your Arimidex treatment.

Note that by lowering your estrogen levels, Arimidex can cause menopausal symptoms such as hot flashes, joint pain, and vaginal dryness. It can also weaken your bones. But you should not take HRT for these side effects.

If you have menopausal symptoms while taking Arimidex, talk with your doctor or pharmacist about alternatives to HRT that can help you manage these symptoms. For example, your doctor may recommend treatments such as acupuncture for joint pain, paroxetine (Brisdelle) for hot flashes, and vaginal lubricants for vaginal dryness.

Your doctor will also likely recommend taking calcium and vitamin D supplements to help prevent osteoporosis while you’re taking Arimidex.

Note that certain herbal supplements recommended for menopausal symptoms should not be taken with Arimidex. For more information about this, see “Arimidex interaction with supplements.”

If you have questions about taking estrogen-containing drugs with Arimidex, talk with your doctor or pharmacist.

Tamoxifen (Soltamox)

Tamoxifen is a medication prescribed to treat certain forms of breast cancer. Similar to Arimidex, it’s a type of hormonal therapy for breast cancer.

Interaction result: Taking Arimidex with tamoxifen can make Arimidex less effective at treating breast cancer.

Interaction explained: Tamoxifen can lower the amount of Arimidex in your blood. This can make Arimidex less effective for you.

Steps you or your doctor may take: Your doctor likely won’t prescribe Arimidex with tamoxifen.

In some cases, your doctor may prescribe Arimidex if tamoxifen has stopped working for your condition. In this case, you should not start Arimidex until after you’ve stopped taking tamoxifen. Your doctor can provide more information about this.

Prasterone (Intrarosa)

Prasterone is a vaginal insert prescribed to treat painful sex caused by vaginal dryness related to menopause.

Interaction result: Using prasterone while taking Arimidex can make Arimidex less effective at treating breast cancer.

Interaction explained: Prasterone is an inactive steroid that your body converts into testosterone and estradiol (a form of estrogen). Using prasterone can increase estrogen levels in your body. Since Arimidex works by lowering estrogen levels, prasterone can oppose the effect of Arimidex.

Steps you or your doctor may take: Your doctor likely won’t prescribe prasterone while you’re taking Arimidex.

Arimidex can cause menopausal symptoms such as vaginal dryness. If you have vaginal dryness, talk with your doctor about ways to manage this. For example, your doctor may recommend using vaginal lubricants or moisturizers.

If you have questions about using prasterone with Arimidex, talk with your doctor or pharmacist.

Arimidex may have other interactions, such as with supplements, foods, vaccines, or even lab tests. You’ll find details below. Keep in mind that the following information does not include all other possible interactions with Arimidex.

Arimidex interactions with supplements

Before you start treatment with Arimidex, tell your doctor and pharmacist which supplements, herbs, and vitamins you take. By sharing this information with them, you may help prevent possible interactions.

You should not take Arimidex with dehydroepiandrosterone (DHEA) supplements because these supplements can make Arimidex less effective. Your body converts DHEA into testosterone and estradiol (a form of estrogen). So taking DHEA can increase estrogen levels in your body. This can oppose the effect of Arimidex, which works by lowering estrogen levels in your body.

If you have questions about other drug interactions that may affect you, ask your doctor or pharmacist.

Arimidex interactions with herbal supplements

There are no specific reports of herbs interacting with Arimidex. However, doctors may recommendTrusted Source avoiding herbal supplements that contain phytoestrogens during Arimidex treatment. Examples of these supplements include red clover, wild yam, and soy isoflavones. Some people use these supplements to help reduce menopausal symptoms, such as hot flashes and vaginal dryness.

Phytoestrogens are compounds with weak estrogen-like effects that are found in certain plants. Arimidex works by lowering estrogen levels in your body. So it’s possible that supplements containing phytoestrogens may oppose the effect of Arimidex and make it less effective at treating breast cancer.

More research is needed to find out for certain if these supplements can affect Arimidex treatment. It’s important to check with your doctor or pharmacist before taking any herbal products during Arimidex treatment.

Arimidex interactions with vitamins

There are no specific reports of Arimidex interacting with vitamins. However, that doesn’t mean vitamin interactions won’t occur or be recognized in the future. Because of this, you should talk with your doctor or pharmacist before taking any vitamin product with Arimidex.

Arimidex interactions with food

Although herbal supplements containing phytoestrogens may interact with Arimidex, it’s unlikely that foods containing phytoestrogens will interact with the drug. This is because the amount of phytoestrogens consumed in food would usually be much less than what’s in an herbal supplement.

If you’d like to learn more about eating certain foods during treatment with Arimidex, talk with your doctor. Your doctor can advise about whether there are any foods to avoid when taking Arimidex.

Arimidex interactions with vaccines

There aren’t any known interactions between Arimidex and vaccines. Talk with your doctor or pharmacist to see whether you’re due for any vaccines.

Arimidex interactions with lab tests

Arimidex isn’t known to interact with any lab tests. If you have concerns about this medication interacting with lab tests, talk with your doctor.

ARIMIDEX INTERACTION WITH CANNABIS OR CBD

Cannabis (often called marijuana) and cannabis products, such as cannabidiol (CBD), have not been specifically reported to interact with Arimidex. However, as with any drug or supplement, talk with your doctor before using cannabis in combination with Arimidex. The impact of cannabis may affect how well you stick to your Arimidex treatment plan.

Note: Cannabis is illegal at a federal level but is legal in many states to varying degrees.

Certain medical conditions and other factors may increase the risk of interactions with Arimidex. Before you take this drug, be sure to talk with your doctor about your health history. Arimidex may not be the right treatment option if you have certain medical conditions or other factors affecting your health.

Health conditions or factors that might interact with Arimidex include:

  • Osteoporosis: Taking Arimidex can lead to weakening of your bones. If you have osteoporosis, weak bones, or a history of fractures, talk with your doctor about whether the drug is right for you. If your doctor prescribes Arimidex, they’ll likely check your bone density more often.
  • Ischemic heart disease: With ischemic heart disease, your heart doesn’t receive enough oxygen due to narrowed arteries that supply blood to your heart. If you have this type of heart disease, taking Arimidex can raise your risk of angina (chest pain) and heart attack. Talk with your doctor about whether the drug is right for you.
  • High cholesterol: Arimidex can increase your cholesterol levels. If you already have high cholesterol, talk with your doctor about whether the drug is right for you. If your doctor prescribes Arimidex, they’ll likely check your cholesterol more often.
  • Liver problems: Arimidex may rarely cause liver problems. If you have a liver problem, Arimidex could make it worse. The drug hasn’t been studied in people with severe liver problems. If you have a liver problem, talk with your doctor about whether Arimidex is safe for you.
  • Allergic reaction: If you’ve had an allergic reaction to Arimidex or any of its ingredients, your doctor will likely not prescribe Arimidex. Taking the drug could cause another allergic reaction. You can ask them about other treatments that may be better choices for you.
  • Breastfeeding: You should not breastfeed while taking Arimidex and for 2 weeks after your last dose. If you’re breastfeeding or planning to, talk with your doctor before using Arimidex. They can talk with you about treatment options and ways to feed a child who is breastfed.
  • Pregnancy: Arimidex is not safe to use while pregnant. Animal studies show that the drug may cause congenital anomalies (commonly known as birth defects) or pregnancy loss. If you’re pregnant or planning to become pregnant, tell your doctor before starting Arimidex. They can advise you on the right treatment plan for you.

Here are some frequently asked questions about Arimidex and possible interactions.

Does Arimidex have interactions with antibiotics?

No, Arimidex is not known to have any interactions with antibiotics. Your doctor may prescribe antibiotics if you have a bacterial infection while taking Arimidex.

If you have other questions about taking Arimidex with antibiotics, talk with your doctor or pharmacist.

Can I take pain relievers with Arimidex?

Yes, it’s typically safe to take pain-relieving drugs with Arimidex. Pain relievers are not known to interact with this medication.

If you need a pain reliever while taking Arimidex, ask your doctor or pharmacist to recommend a medication that’s suitable for you. Learn about OTC pain relievers.

You can take certain steps to help prevent interactions with Arimidex. Your doctor and pharmacist are key resources, so reach out to them before starting treatment. For example, you should plan to do the following:

  • Let them know if you drink alcohol or use cannabis.
  • Tell them about any other medications you take, as well as any supplements, herbs, and vitamins.
  • Create a medication listTrusted Source, which your doctor and pharmacist can help you fill out.

It’s also important to read the Arimidex label and other paperworkTrusted Source that may come with the drug. The label may have colored stickers that mention an interaction. And the paperwork, sometimes called the medication guide or patient package insert, may contain details about interactions.

If Arimidex doesn’t come with paperwork, you can ask your pharmacist to print a copy. If you need help reading or understanding this information, ask your doctor or pharmacist.

You can also help prevent interactions with Arimidex by taking it exactly as your doctor prescribes.

Disclaimer: Medical News Today 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.