Femara is a brand-name oral tablet that’s prescribed for breast cancer in certain people. Femara contains the active ingredient letrozole and belongs to the aromatase inhibitors drug class.

Femara is approved by the Food and Drug Administration (FDA) to treat breast cancer in females* who’ve gone through menopause.

Femara is prescribed for females with certain forms of either early or advanced breast cancer. With early breast cancer, the cancer hasn’t spread out of either your breast or the lymph nodes in your armpit. But with advanced breast cancer, the cancer has spread to nearby areas or lymph nodes (called locally advanced breast cancer), or it has spread to other parts of the body (called metastatic breast cancer).

Femara is used in the following ways for early HR+ breast cancer:

  • Adjuvant treatment: For this use, Femara is given to help lower the risk of the breast cancer coming back after it’s been treated with surgery.
  • Extended adjuvant treatment: For this use, Femara is given to help lower the risk of the breast cancer coming back after it’s been treated with both surgery and 5 years of tamoxifen (another cancer drug).

Femara is used in the following ways for advanced breast cancer that’s either HR+ or its hormone receptor status isn’t known:

  • First-line treatment: With first-line treatment, Femara is the first drug given to treat the advanced breast cancer.
  • Second-line treatment: With second-line treatment, Femara is given to treat the advanced breast cancer after certain past therapy hasn’t worked. For this use, Femara can treat advanced breast cancer that has come back or spread after other treatments.

Femara is also used off-label to treat infertility. Off-label use is when a drug that’s approved to treat one condition is used to treat another condition. For more information about this use of Femara, see the section “Off-label use of Femara for infertility” below.

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

Drug details

You’ll find key information about Femara below.

  • Drug class: aromatase inhibitors, which is a type of hormone therapy for breast cancer
  • Drug form: oral tablet
  • Generic available? yes
  • Prescription required? yes
  • Controlled substance? no
  • Year of FDA approval: 2001

Femara tablets contain the active drug letrozole. Generic forms of Femara are available.

A generic drug is an exact copy of a brand-name medication. The generic is considered to be as safe and effective as the original drug. And generics tend to cost less than brand-name drugs.

Femara can cause mild or serious side effects. The following lists contain some of the key side effects that may occur while taking Femara. These lists do not include all possible side effects.

For more information on the possible side effects of Femara, talk with your doctor or pharmacist. They can give you tips on how to manage any side effects that may be bothersome.

Note: The Food and Drug Administration (FDA) tracks side effects of drugs they have approved. If you would like to report to the FDA a side effect you’ve had with Femara, you can do so through MedWatch.

Mild side effects

The mild side effects of Femara that are more common can include:

  • hot flashes
  • flushed skin
  • increased sweating
  • joint pain
  • weakness
  • edema (swelling), possibly in your ankles or feet
  • headache
  • dizziness
  • bone pain

The mild side effects of Femara that are less common can include:

Most of these side effects may go away within a few days or a couple of weeks. But if they become more severe or don’t go away, talk with your doctor or pharmacist.

Serious side effects

Serious side effects from Femara aren’t common, but they can occur. Call your doctor right away if you have serious side effects. Call 911 if your symptoms feel life threatening or if you think you’re having a medical emergency.

Serious side effects, which are explained in more detail below in “Side effect details,” include:

Side effect details

You may wonder how often certain side effects occur with this drug. Here’s some detail on several of the side effects this drug can cause. To learn more about the side effects of Femara, see this in-depth article.

Reduced bone mineral density

Femara may cause reduced bone mineral density (weakened bones) in some people. Femara, which works by lowering your estrogen level, is prescribed for females* who’ve gone through menopause.

Estrogen helps to keep your bones strong. But after menopause, your estrogen levels fall, which can weaken your bones. And because Femara also lowers your estrogen level, the drug can add to this effect. This increases your risk of breaking a bone during Femara treatment.

To find out how often this side effect occurred in clinical studies, see the drug’s prescribing information. If you have questions or concerns about this potential side effect, talk with your doctor or pharmacist.

If you’re taking Femara, your doctor may want to measure your bone mineral density. This allows them to monitor how strong your bones are. If your bones become weak during treatment, your doctor may prescribe medication for you to help strengthen your bones.

There are also some things you can do to help minimize loss of bone strength while you’re taking Femara. If you have questions about how Femara may affect your bone density, talk with your doctor.

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

Allergic reaction

As with most drugs, some people can have an allergic reaction after taking Femara. But it’s not known how often this occurs in people using Femara.

Symptoms of a mild allergic reaction can include:

A more severe allergic reaction is rare but possible. Symptoms of a severe allergic reaction can include:

  • swelling under your skin, typically in your eyelids, lips, hands, or feet
  • swelling of your tongue, mouth, or throat
  • difficulty breathing

Call your doctor right away if you have a severe allergic reaction to Femara. Call 911 if your symptoms feel life threatening or if you think you’re having a medical emergency.

Fatigue or dizziness

For some people, Femara may cause fatigue or dizziness. To find out how often these side effects occurred in clinical studies, see the drug’s prescribing information. If you have questions or concerns about these potential side effects, talk with your doctor or pharmacist.

If you have fatigue or dizziness while you’re taking Femara, don’t drive or operate other machines. You shouldn’t drive or operate machinery until you know how the drug will affect you. And talk with your doctor about ways to help improve your energy level during treatment.

Weight gain or weight loss

Your body weight may change while you’re taking Femara. During clinical studies, both weight gain and weight loss were reported in people who took Femara for breast cancer treatment.

Both cancer and cancer treatments can often cause changes in appetite and body weight. If you have questions or concerns about changes in your weight, talk with your doctor or pharmacist.

Side effects after stopping Femara

Stopping Femara treatment isn’t known to cause side effects. And this medication doesn’t need to be stopped gradually.

In certain situations, if Femara has stopped working for you, your doctor might ask you to stop taking the drug in order to cause a “withdrawal response.” This response is a hormonal shift that’s caused by stopping Femara.

In this case, stopping Femara can sometimes improve your breast cancer, rather than causing side effects. However, this particular treatment approach isn’t right for everyone.

If your doctor thinks Femara has stopped working for you, talk with them about whether stopping treatment could be beneficial for you.

The Food and Drug Administration (FDA) approves prescription drugs such as Femara to treat certain conditions. But sometimes Femara is used off-label for other conditions. Off-label use is when a drug that’s approved to treat one condition is used to treat a different condition.

Femara is used off-label to treat infertility in females.* It’s mainly used when infertility is caused by problems with ovulation (the release of eggs from your ovaries). The most common cause of ovulation problems that result in infertility is polycystic ovary syndrome (PCOS).† But Femara is also sometimes used to treat infertility that doesn’t have an obvious cause.

In all of these cases, Femara is used to treat infertility by inducing (causing) ovulation. For this use, you’ll take Femara for a few days after the start of your period. Doing this temporarily lowers your estrogen level.

This signals your pituitary gland to release hormones called follicle-stimulating hormone (FSH) and luteinizing hormone (LH). These hormones stimulate an egg in your ovary to mature and be released from your ovary. This is how Femara causes ovulation. This use of the drug is called ovulation induction.

If you’re already ovulating before taking Femara, the drug may cause more eggs than usual to mature and be released from your ovaries. This condition is called controlled ovarian hyperstimulation or superovulation.

To learn more about infertility and its causes, you can see our list of fertility articles.

* Sex and gender exist on spectrums. Use of the term “female” in this article refers to the sex assigned at birth.
† PCOS is a condition that can cause hormone problems, irregular or skipped periods, and cysts on your ovaries. Oftentimes, people with PCOS don’t ovulate as usual, so they have difficulty getting pregnant.

Effectiveness for infertility

Taking Femara can help you to become pregnant if you’re trying to conceive (TTC) by either having sexual intercourse or using intrauterine insemination (IUI). But actual rates of using Femara for getting pregnant or carrying a pregnancy depend on many factors. These include:

  • the cause of your infertility
  • your age
  • whether you’re using Femara with other fertility treatments

You’re more likely to be able to carry a pregnancy with Femara treatment for infertility if your body isn’t already ovulating.

To find out how effective Femara was for infertility in clinical studies, see the drug’s prescribing information. If you have questions or concerns about using Femara for infertility, talk with your doctor.

International guidelines recommend letrozole (the active drug in Femara) as an effective treatment for infertility.

Dosage for infertility

The usual dosage of Femara for inducing ovulation is 2.5 milligrams (mg) taken by mouth once daily for 5 days. Your doctor may ask you to start taking the drug either on day 3 or day 5 of your menstrual cycle. (Day 1 of your menstrual cycle is the first day of your period.) If you’re not having periods when starting Femara, your doctor will recommend when you should start taking the drug.

Sometimes your doctor may recommend that you take a higher dosage of Femara, such as 5 mg or 7.5 mg daily for 5 days.

The highest dose of Femara for fertility treatment hasn’t been determined. More research is needed to know whether higher doses of Femara are more effective than lower doses. Be sure to always take the dosage of Femara that’s prescribed by your doctor.

Side effects when using Femara for infertility

Examples of both mild and serious side effects that can occur when using Femara for infertility include:

  • dizziness
  • fatigue
  • hot flashes
  • breast tenderness
  • mood swings
  • night sweats
  • nausea
  • vomiting
  • spotting (light vaginal bleeding between periods)
  • ovarian cysts
  • rarely, ovarian hyperstimulation syndrome (OHSS), which occurs when more eggs than usual develop in your ovaries

How to take Femara for infertility

You’ll usually take Femara by mouth once daily for 5 days after the start of your menstrual cycle. Your doctor might ask you to take Femara on either cycle days 3 to 7 or cycle days 5 to 9. (Day 1 of your menstrual cycle is the first of your period.) Be sure to always take Femara exactly as your doctor recommends.

Ovulation tends to occur between 5 and 10 days after you’ve taken your last Femara tablet. Your doctor will usually recommend using an ovulation predictor test to help you know when you’re about to ovulate.

Your doctor will also advise when you should start having sex if you’re trying to conceive (TTC) naturally. Or if you’re using IUI, you doctor will recommend when you should go into the clinic for artificial insemination.

What’s the best time of day to take Femara for infertility?

You can take Femara at any time of day. But try to take it around the same time on each of the 5 days that you’re taking the drug.

How long can you take Femara for fertility treatment?

Most doctors won’t prescribe Femara for more than six cycles of treatment. This is because if you haven’t gotten pregnant after six treatment cycles, it’s likely that this drug won’t work for you.

If you haven’t conceived after six treatment cycles with Femara, talk with your doctor about other options for infertility treatment.

Femara vs. Clomid

Femara contains the active drug letrozole, while Clomid contains the active drug clomiphene. Clomid has been discontinued, but generic versions of clomiphene are still available.

Femara and clomiphene are both used to induce (cause) ovulation in females* who are having difficulty getting pregnant. For these people, infertility may be caused by problems with ovulation, or it may not have an obvious cause (called unexplained infertility).

Femara is used off-label for this purpose. (Off-label use is when a drug that’s approved for one condition is used to treat another.) However, clomiphene is FDA-approved for treating infertility in females.

Femara and clomiphene work in slightly different ways in your body to induce ovulation. But both drugs are usually taken for 5 days at the start of your menstrual cycle.

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

Effectiveness of Femara and clomiphene

Whether Femara or clomiphene is more effective for you may depend on the cause of your infertility. But studies comparing the two drugs have found slightly differing results.

A 2023 study found Femara to be more effective than clomiphene in treating infertility in people with PCOS. A 2019 review of studies also found Femara to be more effective than clomiphene in treating infertility in females* with PCOS. Another 2019 review of studies found Femara and clomiphene to be similarly effective in treating unexplained infertility.

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

Alternatives for infertility

Many drugs are available to treat infertility. Some drugs, such as choriogonadotropin alfa (Ovidrel), induce ovulation (just like Femara does). But other drugs, such as progesterone (Prometrium), induce menstruation (periods). And there are other drugs used to treat infertility that do other things in your body.

If you’d like to know more about treatment options for infertility, talk with your doctor.

The Food and Drug Administration (FDA) approves prescription drugs such as Femara to treat certain conditions.

Femara is a hormone therapy that’s approved to treat certain forms of breast cancer in females who’ve gone through menopause.

Hormone therapies stop estrogen from encouraging breast cancer cells to grow. More specifically, Femara is a type of hormone therapy called an aromatase inhibitor. It works by stopping an enzyme (type of protein) called aromatase from working as usual. This enzyme is the main way that your body makes estrogen after you’ve gone through menopause.

Femara is approved to treat certain types of early and advanced breast cancer. See the sections “Femara for advanced breast cancer” and “Femara for adjuvant treatment of early breast cancer” below for more information.

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

Femara for advanced breast cancer

Femara is FDA-approved to treat advanced breast cancer that’s hormone receptor-positive (HR+). With advanced breast cancer, the cancer has spread to nearby areas or lymph nodes (called locally advanced breast cancer), or it has spread to other parts of the body (called metastatic breast cancer).

HR+ breast cancer is encouraged to grow by hormones, including estrogen. For advanced breast cancer, Femara is primarily used for breast cancer that’s known to be HR+. But because most breast cancers are HR+, Femara can also be used to treat advanced breast cancer, the HR status of which isn’t known.

Femara is used in the following ways to treat advanced breast cancer:

  • First-line treatment: With first-line treatment, Femara is the first drug given to treat the advanced breast cancer.
  • Second-line treatment: With second-line treatment, Femara is given to treat advanced breast cancer after certain past therapy hasn’t worked. For this use, Femara can treat advanced breast cancer that has come back or spread after other treatments.

To learn more about your condition, visit our breast cancer hub.

Effectiveness for advanced breast cancer

Femara has been found to be effective in treating advanced breast cancer. In fact, aromatase inhibitors such as Femara are recommended in current guidelines for people with HR+ breast cancer. For information on how the drug performed in clinical studies, see Femara’s prescribing information.

Femara for adjuvant treatment of early breast cancer

Femara is FDA-approved for adjuvant treatment of early breast cancer that’s hormone receptor-positive (HR+). With early breast cancer, the cancer hasn’t spread out of either your breast or the lymph nodes in your armpit. HR+ breast cancer is encouraged to grow by hormones, including estrogen.

Adjuvant treatment of breast cancer is treatment that’s taken to reduce the risk of the cancer coming back after surgery. For this use, you’ll usually take the drug for 5 years following surgery to remove the cancer.

Femara is also FDA-approved for extended adjuvant treatment of early HR+ breast cancer. For this use, you’ll usually take Femara for 5 years after you’ve already taken tamoxifen for 5 years following surgery to remove the cancer.

Talk with your doctor about how long you should take Femara for adjuvant treatment of breast cancer. Your doctor will help you to weigh potential risks and benefits of taking Femara for a long period of time. Risks of extended treatment to consider may include weakening of your bones or raised cholesterol levels.

To learn more about your condition, visit our breast cancer hub.

Effectiveness for adjuvant treatment of early breast cancer

Femara has been found to be effective in treating early breast cancer. In fact, aromatase inhibitors such as Femara are recommended in current guidelines for people with HR+ breast cancer. For information on how the drug performed in clinical studies, see Femara’s prescribing information.

Off-label uses for Femara

In addition to the uses listed above, Femara may be used off-label. Off-label drug use is when a drug that’s approved for one use is used for a different one that’s not approved. Below are examples of off-label uses for Femara.

Femara for infertility in females

Femara isn’t FDA-approved to treat infertility, but sometimes it’s used off-label for this purpose in females. For more information about using Femara for infertility, see the section “Off-label use of Femara for infertility” above.

To learn more about infertility and its causes, you can see our list of fertility articles.

Femara for infertility in males

Femara isn’t approved to treat infertility in males. However, it’s sometimes used off-label for this use. In addition, a study found that Femara may be effective in treating infertility in males who have both obesity and low testosterone levels.

If you’re interested in using Femara for this purpose, talk with your doctor. To learn more about infertility and its causes, you can see our list of fertility articles.

Femara for PCOS

Femara isn’t approved to treat polycystic ovary syndrome (PCOS). But sometimes the drug is used off-label to treat infertility in females with PCOS.

PCOS is a condition that causes hormone problems, irregular or skipped periods, and cysts on your ovaries. Oftentimes people with PCOS don’t ovulate like usual, so they have difficulty becoming pregnant.

Femara induces (causes) ovulation and can increase your probability of becoming pregnant. For more information about using Femara to treat infertility, see the section “Off-label use of Femara for infertility” above.

If you’d like to know about using Femara for this purpose, talk with your doctor. And to learn more about your condition, see our list of PCOS articles.

Femara for endometriosis

Femara isn’t approved to treat endometriosis. But sometimes the drug is used off-label in people with this condition.

With endometriosis, tissue that’s similar to the tissue lining your uterus grows in other parts of your body. This condition can become very painful and may lead to infertility in some people.

Femara is sometimes used off-label to help manage pain related to endometriosis in females who haven’t experienced the desired results from other treatments. It’s typically used in combination with a progestin hormone for this use.

Femara is also sometimes used off-label to treat infertility in females with endometriosis. Femara induces (causes) ovulation and can increase your probability of becoming pregnant. For more information about using Femara for infertility, see the section “Off-label use of Femara for infertility” above.

If you’d like to know about using Femara for these purposes, talk with your doctor. And to learn more about your condition, see our list of endometriosis articles.

As with all medications, the cost of Femara can vary. The actual price you’ll pay depends on your insurance plan, your location, and the pharmacy you use.

Your insurance plan may require you to get prior authorization before approving coverage for Femara. This means that your doctor and insurance company will need to communicate about your prescription before the insurance company will cover the drug. The insurance company will review the request and let you and your doctor know if your plan will cover Femara.

If you’re not sure if you’ll need to get prior authorization for Femara, contact your insurance company.

Drug coupons: You can visit Optum Perks for price estimates of Femara. These estimates are based on the use of Optum Perks coupons. Note: Optum Perks coupons cannot be used with any insurance copays or benefits.

Financial and insurance assistance: If you need financial support to pay for Femara, or if you need help understanding your insurance coverage, help is available.

A program called Novartis Patient Support for Oncology is available for Femara. For more information and to find out whether you’re eligible for support, call 800-282-7630 or visit the program website. You can also visit Medicine Assistance Tool to find programs that may help lower your cost of Femara.

Generic version: Femara contains the active drug letrozole, which is available in generic forms. A generic drug is an exact copy of the active ingredient in a brand-name medication. The generic is considered to be as safe and effective as the original drug. And generics tend to cost less than brand-name drugs. To find out how the cost of letrozole compares to the cost of Femara, talk with your doctor or pharmacist.

To learn more about saving money on prescriptions, check out this article. For more information about the cost of Femara, see this article.

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Femara shouldn’t be taken during pregnancy. This is because both animal studies and reports of use by pregnant females* suggest that Femara may cause problems with fetal development, congenital anomalies (commonly known as birth defects), and pregnancy loss.

Also, keep in mind that Femara isn’t approved to treat breast cancer in females who haven’t gone through menopause yet.

If you think you could be pregnant or have pregnancy symptoms, tell your doctor before you start taking Femara.

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

Femara’s effect on pregnancy when it’s used off-label for infertility

When Femara is used off-label to treat infertility, the drug doesn’t increase the risk of congenital anomalies or pregnancy loss. It only has these risks if it’s taken when you’re already pregnant. (With off-label use, a drug that’s approved to treat one condition is used to treat another.)

When you take Femara to induce (cause) ovulation, the drug is cleared from your body within several days after you’ve stopped taking it. This means that Femara will no longer be in your body when you ovulate or conceive.

If you have questions about the risks of Femara use in pregnancy, talk with your doctor.

Femara can cause problems with fetal development, congenital anomalies (commonly known as birth defects), and pregnancy loss if it’s taken during pregnancy. If you’re sexually active and you or your partner can become pregnant, talk with your doctor about your birth control needs while you’re using Femara.

It’s not known if Femara passes into breast milk. But the drug could be harmful to a child who consumes it through breast milk. Because of this, you shouldn’t breastfeed while you’re taking Femara. And you should continue to avoid breastfeeding for at least 3 weeks after your last dose of the drug.

If you’re breastfeeding, talk with your doctor before you start taking Femara.

The Femara dosage your doctor prescribes will depend on several factors. These include:

  • the condition you’re taking Femara to treat
  • how well your liver works

The following information describes dosages that are commonly used or recommended. However, be sure to take the dosage your doctor prescribes for you. Your doctor will determine the best dosage to fit your needs.

You can also see this comprehensive article about Femara’s dosage.

Drug forms and strengths

Femara comes as 2.5-mg tablets that are taken by mouth.

Dosage for breast cancer

The usual dosage of Femara for breast cancer treatment is one tablet taken by mouth once each day.

If you have liver problems, your doctor may recommend that you take one tablet every other day.

In any case, your doctor will recommend how long to keep taking Femara.

Dosage for adjuvant treatment of breast cancer

The usual dosage of Femara for adjuvant treatment of breast cancer is one tablet taken by mouth once each day.

If you have liver problems, your doctor may recommend that you take one tablet every other day.

You should keep taking Femara for as long as your doctor recommends.

What if I miss a dose?

If you miss a dose of Femara, take it as soon as you remember, unless it’s almost time for your next dose. In that case, just skip the missed dose and take your next dose as scheduled. Don’t take two doses together to make up for a missed dose.

To help make sure that you don’t miss a dose, try setting a reminder on your phone. A medication timer may be useful, too.

Will I need to use this drug long term?

Femara is meant to be used as a long-term treatment for breast cancer. If you and your doctor determine that Femara is safe and effective for you, you’ll likely take it long term.

Here are answers to some frequently asked questions about Femara.

Is Femara a chemotherapy drug?

No, Femara isn’t a chemotherapy drug. Chemotherapy describes traditional drugs used to treat cancer. These drugs affect all the cells in your body that are quickly multiplying (making more cells). Cancer cells multiply quickly, but some healthy cells in your body also multiply quickly. This means that chemotherapy can affect both cancer cells and healthy cells.

Instead, Femara is a hormone therapy. It works by lowering the level of estrogen in your body. This helps slow the growth and spread of cancer that’s encouraged to grow by estrogen.

How long does Femara stay in your system?

Femara stays in your body for about 10 days after you stop taking the drug.

Will I have withdrawal symptoms when I stop taking Femara?

No, you likely won’t. Withdrawal symptoms are side effects that can happen when you stop taking a drug that your body has become dependent on. (With dependence, your body needs the drug in order to function like usual.) Stopping Femara isn’t known to cause any withdrawal symptoms.

If you have questions about any symptoms after stopping Femara, talk with your doctor.

Other drugs are available that can treat breast cancer. Some may be a better fit for you than others. If you’re interested in finding an alternative to Femara, talk with your doctor. They can tell you about other medications that may work well for you.

Examples of other drugs that may be used to treat breast cancer include:

  • hormone therapies, other than Femara, such as:
  • targeted therapies, such as:
  • chemotherapy (traditional drugs used to treat cancer), such as:
    • doxorubicin (Adriamycin)
    • epirubicin (Ellence)
    • paclitaxel (Abraxane)
    • docetaxel (Taxotere)
    • capecitabine (Xeloda)
    • cyclophosphamide

Femara is approved to treat certain types of breast cancer in females* who’ve already gone through menopause.

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

What happens in breast cancer?

Breast cancer develops when cells in your breast tissue start to grow and multiply more quickly than usual. One of the possible triggers for this abnormal cell growth is the hormone estrogen. Breast cancers that are stimulated by hormones, such as estrogen, are called hormone receptor-positive (HR+). These cancers can be treated with hormone therapies that work by lowering estrogen levels in your body.

What does Femara do?

Femara is a hormone therapy that’s used for HR+ breast cancer. It’s a type of drug called an aromatase inhibitor. Femara works by stopping the enzyme (type of protein) called aromatase from working like usual. (Enzymes help chemical reactions in your body to happen.)

The aromatase enzyme helps make estrogen from other hormones called androgens. One example of an androgen is the hormone testosterone.

After you’ve gone through menopause, your ovaries no longer produce estrogen. At that point, the aromatase enzyme is the main pathway that your body uses to make estrogen. By stopping aromatase from working, Femara lowers the amount of estrogen in your body. This stops estrogen from being able to stimulate breast cancer cells to grow and multiply.

How long does it take to work?

Femara will start working soon after you start taking it. But you won’t be able to notice it working in your body. Your doctor may order tests from time to time to check and see if the drug is working for you. For example, they may order imaging tests to see if your cancer tumors are shrinking.

You should take Femara according to your doctor’s or another healthcare professional’s instructions.

When to take

For breast cancer treatment, you’ll usually take Femara once each day. But if you have liver problems, your doctor may recommend that you take the drug once every other day.

You can take your dose at any time of the day. But try to always stick to the same time each day. To help make sure that you don’t miss a dose, try setting a reminder on your phone. A medication timer may be useful, too.

Taking Femara with food

You can take Femara with or without food.

Can Femara be crushed, split, or chewed?

No, Femara tablets should be swallowed whole. They shouldn’t be crushed, split, or chewed. If you have difficulty swallowing Femara tablets, talk with your doctor or pharmacist about ways to help make it easier for you to take your medication.

Alcohol isn’t known to interact with Femara. However, if you find that Femara gives you a headache, or makes you feel dizzy, nauseous, or tired, drinking alcohol may worsen these side effects.

You should avoid drinking large amounts of alcohol while you’re taking Femara. This is because drinking a lot of alcohol can increase your risk of osteoporosis, which is already increased by the drug. (With osteoporosis, you have weak, thin bones.)

It’s also worth noting that alcohol is known to increase the risk of developing breast cancer. But it’s not known if drinking alcohol after you’re diagnosed with breast cancer can make your cancer worse or more likely to come back after treatment.

If you drink alcohol and you’re concerned about how this might affect your condition, talk with your doctor. They can recommend how much alcohol is safe for you to drink during Femara treatment.

Femara can interact with some other medications. It can also interact with certain supplements as well as certain foods.

Different interactions can cause different effects. For instance, some interactions can interfere with how well a drug works. Other interactions can increase side effects or make them more severe.

Femara and other medications

Below are lists of medications that can interact with Femara. These lists do not contain all the drugs that may interact with Femara.

Before taking Femara, talk with your doctor and pharmacist. Tell them about all prescription, over-the-counter, and other drugs you take. Also tell them about any vitamins, herbs, and supplements you use. Sharing this information can help you avoid potential interactions.

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

Drugs that should not be used with Femara

The following drugs should not be used while you’re taking Femara:

  • Tamoxifen: You shouldn’t take Femara with tamoxifen, which is another drug used to treat breast cancer. Taking these drugs together can make Femara less effective.
  • Drugs that contain estrogen: You shouldn’t take any drugs that contain estrogen with Femara. Taking Femara with these drugs could make Femara less effective. Examples of drugs that contain estrogen include:

Femara and herbs and supplements

There aren’t any herbs or supplements that have been specifically reported to interact with Femara.

However, it’s possible that certain plant-based estrogens (called phytoestrogens) could make Femara less effective. Phytoestrogens are supplements made from plants. They’re sometimes used by some people to help manage menopausal symptoms, such as hot flashes.

Always check with your doctor or pharmacist before using any herbs or supplement products while you’re taking Femara.

Before taking Femara, talk with your doctor about your health history. Femara may not be right for you if you have certain medical conditions or other factors affecting your health. These include:

  • Allergy to Femara: You shouldn’t take Femara if you’ve ever had an allergic reaction to letrozole (the active drug in Femara) or to any of Femara’s inactive ingredients in the past. If you’re not sure about your medication allergies, talk with your doctor.
  • Liver problems: Femara is cleared from your body by your liver. If you have cirrhosis (liver scarring) or severe problems with your liver, you may need a lower dosage of Femara. For example, your doctor may recommend that you take Femara once every other day, instead of every day as usual. Talk with your doctor about any history of liver problems before starting Femara.
  • High cholesterol level: Femara can increase your cholesterol level. Because of this, you’ll have blood tests to check your cholesterol level while you’re taking the drug. If your cholesterol rises too high, you may need medication to lower it.
  • Osteoporosis: Taking Femara can weaken your bones. This can cause new or worsening osteoporosis (weak, thin bones). It can also increase your risk of bone fractures. Your doctor may measure your bone mineral density while you’re taking Femara. If you already have osteoporosis, or risk factors for developing this condition, you may need medication to help protect your bones during Femara treatment. (These risk factors include a family history of osteoporosis, limited physical activity, smoking, drinking alcohol, and not getting enough calcium or vitamin D.)
  • Pregnancy: Don’t take Femara if you’re pregnant. For more information about the risks of using this drug during pregnancy, see the “Femara and pregnancy” section above.
  • Breastfeeding: Don’t take Femara if you’re breastfeeding. For more information, see the “Femara and breastfeeding” section above.

Note: For more information about the potential negative effects of Femara, see the “Femara side effects” section above.

Taking more than the recommended dosage of Femara may result in overdose in some people. But it’s not known for sure what symptoms you may have from overdose.

What to do in case of overdose

If you think you’ve taken too much of this drug, call your doctor. You can also call America’s Poison Centers at 800-222-1222 or use its online tool. But if your symptoms are severe, call 911 or go to the nearest emergency room right away.

When you get Femara from the pharmacy, the pharmacist will add an expiration date to the label on the bottle. This date is typically 1 year from the date they dispensed the medication.

The expiration date helps guarantee that the medication is effective during this time. The current stance of the Food and Drug Administration (FDA) is to avoid using expired medications. If you have unused medication that has gone past the expiration date, ask your pharmacist how to correctly dispose of it.

Storage

How long a medication remains good can depend on many factors, including how and where you store the medication.

Femara tablets should be stored at room temperature (77°F/25°C) in a tightly sealed container. Avoid storing this medication in areas where it could get damp or wet, such as in bathrooms.

Disposal

If you no longer need to take Femara and have leftover medication, it’s important to dispose of it safely. This helps prevent others, including children and pets, from taking the drug by accident. It also helps keep the drug from harming the environment.

The FDA website provides several useful tips on medication disposal. You can also ask your pharmacist for information on how to dispose of your medication.

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.

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