Faslodex (fulvestrant)

Faslodex generic

Faslodex is available as a brand-name medication. It is also available in a generic form called fulvestrant.

A generic drug is an exact copy of the active ingredient in a brand-name medication. Generics tend to cost less than brand-name drugs.

Faslodex side effects

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

For more information on the possible side effects of Faslodex, see this article. You can also talk with your doctor or pharmacist. They can give you tips on how to deal with any side effects that may be bothersome.

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

Mild side effects

The mild side effects of Faslodex that occurred in clinical trials include:

• back pain
• fatigue
• pain in the arms or legs
• hot flashes
• nausea
• bone pain
• joint pain
• pain at the injection site (See “Side effect details” below.)
• headache
• hair loss (See “Side effect details” below.)
• low appetite that can lead to weight loss (See “Side effect details” below.)

Most of the side effects listed above are for a dose of Faslodex when it’s taken alone. If you’re taking Faslodex along with other medications for your breast cancer, you may have side effects from those medications as well.

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 Faslodex 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 and their symptoms can include:

• Elevated liver enzymes (the level of these enzymes in the blood shows how well a person’s liver is working). Symptoms can include:
  • abdominal pain
  • jaundice
  • dark urine
• Bleeding. Symptoms can include:
  • bruising easily
  • bleeding that doesn’t easily stop after getting cut
• Allergic reaction. See “Side effect details” below.

Side effect details

You may wonder how often certain side effects occur with this drug or whether certain side effects pertain to it. Here’s some detail on several of the side effects this drug may or may not cause.

Allergic reaction

As with most drugs, some people can have an allergic reaction after taking Faslodex. Symptoms of a mild allergic reaction can include:

• skin rash
• itchiness
• flushing

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
• trouble breathing or speaking

It’s not known how many people in clinical trials had an allergic reaction to Faslodex. Call your doctor right away if you have a severe allergic reaction to Faslodex. Call 911 if your symptoms feel life threatening or if you think you’re having a medical emergency.

Weight gain or weight loss

Taking Faslodex may cause you to lose weight. This is because it can lower your appetite, which makes you not want to eat as much or as often.

Although a low appetite is a fairly common side effect, weight loss was not very common in clinical trials of Faslodex.

Weight gain is not a side effect that occurred in clinical trials of this drug. It’s unlikely that Faslodex will cause you to gain weight. Talk with your doctor if you’re concerned about your appetite or if you’re experiencing weight changes during your treatment.

Hair loss

In clinical trials, hair loss was a side effect seen in females taking Faslodex along with other drugs to treat their breast cancer. However, it was not reported as a common side effect in people taking Faslodex by itself to treat their breast cancer.

Talk with your doctor if you’re concerned about hair loss during your cancer treatment.

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

Injection site pain

Some people taking Faslodex may experience pain at the injection site, a side effect reported in clinical trials. Because Faslodex is injected into the muscles of your buttock, it may cause pain in that area.

There have also been reports of nerve damage related to the injection of Faslodex. Faslodex is injected into the buttocks, which is close to the sciatic nerve (a large nerve that travels from your spine into the back of your leg). Because of this, the injection could cause nerve pain or nerve damage.

However, this was not a commonly reported side effect in those taking Faslodex in clinical trials. It’s not known how many people have experienced nerve damage from a Faslodex injection.

Talk with your doctor right away if you’re having severe injection site pain or a burning or shooting pain near the injection site.

Faslodex for breast cancer

The Food and Drug Administration (FDA) approves prescription drugs such as Faslodex to treat certain conditions. Faslodex may also be 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.

Faslodex is approved to treat certain types of hormone receptor-positive (HR-positive) breast cancer in females. With HR-positive breast cancer, the cancer is dependent on certain hormones, such as estrogen or progesterone, to grow and spread. The FDA has not approved Faslodex for use in males or children.

Faslodex is a hormone therapy that works by lowering the levels of these hormones in your body. When these hormone levels are reduced, HR-positive breast cancers can’t grow as easily. This can help stop the spread of your cancer or get rid of it completely.

To learn more about this type of cancer, see our breast cancer hub.

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

Faslodex for HR-positive, HER2-negative breast cancer

Faslodex is approved to treat HR-positive breast cancer that’s HER2-negative. This means the cancer cells don’t have abnormally high levels of a protein called HER2.

In females who haven’t had past treatments

If you’ve never had treatment for your HR-positive, HER2-negative advanced breast cancer before, you can take Faslodex as your first treatment. For this purpose, Faslodex is only approved for use in postmenopausal females. (Postmenopausal females have already gone through menopause.)

If your cancer is advanced or metastatic (has spread to other areas of your body), your doctor may have you start taking Faslodex and ribociclib (Kisqali) at the same time.

In females whose past treatments didn’t work

If you have been treated before for HR-positive, HER2-negative advanced or metastatic breast cancer and your cancer got worse after hormone therapy, your doctor may have you start taking Faslodex with other medications. In this case, you may take Faslodex with palbociclib (Ibrance), abemaciclib (Verzenio), or ribociclib (Kisqali). Faslodex is only approved for use with ribociclib in postmenopausal females.

Faslodex for HR-positive advanced breast cancer

Faslodex is also approved for use in postmenopausal females with advanced HR-positive breast cancer who’ve tried hormone therapy before and whose breast cancer got worse after taking it. (This is regardless of HER2 status.) For this purpose, Faslodex is used alone.

Effectiveness for breast cancer

In clinical trials, Faslodex was found to be effective at treating the types of breast cancer described above. For details about these clinical trials, see the Faslodex prescribing information.

Faslodex use with other drugs

Sometimes Faslodex is used along with other drugs to treat breast cancer. This is often done when the breast cancer is metastatic (has spread to other parts of the body) and additional treatment is needed. It’s also done when the breast cancer is aggressive and needs to be treated with multiple medications at once to stop it from getting worse.

Faslodex is approved to be used with the following medications:

• palbociclib (Ibrance)
• abemaciclib (Verzenio)
• ribociclib (Kisqali)

Faslodex with other drugs in premenopausal females

Faslodex is approved for use in females whose advanced or metastatic breast cancer is hormone receptor-positive (HR-positive) and HER2-negative. The cancer also must have worsened after previous hormone therapy. (This type of treatment works by blocking hormones that may be contributing to the growth of the cancer.) Faslodex is approved for this use regardless of whether you’ve gone through menopause.

However, if you’re a premenopausal female (haven’t started menopause yet) and you want to take Faslodex, you must also take a drug to lower the amount of estrogen your ovaries produce. (In premenopausal females, the ovaries are the main producers of estrogen.)

With HR-positive breast cancer, more estrogen means the cancer grows more quickly. By blocking the large amounts of estrogen produced in a premenopausal female’s ovaries, the cancer growth can be slowed or stopped completely.

Examples of medications that may be used to decrease estrogen produced by the ovaries include:

• leuprolide acetate (Lupron Depot)
• goserelin (Zoladex)

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

Use with Ibrance or Verzenio

Faslodex is approved for use with palbociclib (Ibrance) or abemaciclib (Verzenio) in females with HR-positive, HER2-negative advanced or metastatic breast cancer. It’s approved for this use if you’ve already tried hormone therapy and your cancer got worse.

Use with Kisqali

Faslodex is approved for use with ribociclib (Kisqali) in postmenopausal females with HR-positive, HER2-negative advanced or metastatic breast cancer. In this case, it can be used as the first hormone therapy you’ve tried or after you’ve tried another hormone therapy and your cancer got worse.

How Faslodex is administered

Faslodex is given as an injection by your doctor or a healthcare professional.

Injection site for Faslodex

You’ll receive Faslodex as an injection into the muscles of your buttocks. Each dose is two injections. One syringe will be injected into your right buttock and the other into your left buttock. It’s a slow process that takes about 1 to 2 minutes per injection.

When to receive

Faslodex is usually injected on days 1, 15, and 29 of your treatment. This means that for the first three doses, the injections are about 2 weeks apart. After that, you’ll need to get Faslodex injections only once per month.

To help make sure you don’t miss an appointment to get your Faslodex dose, try setting a reminder on your phone.

Faslodex dosage

The Faslodex dosage your doctor prescribes may depend on other medical conditions you have.

Your doctor will ultimately prescribe the smallest dosage that provides the desired effect.

The following information describes dosages that are commonly used or recommended. However, your doctor will determine the best dosage to fit your needs.

For more details on Faslodex’s dosage, see this article.

Drug forms and strengths

Faslodex comes as a solution that’s used for intramuscular injection. Specifically, a doctor or healthcare professional injects the medication into the muscles of the buttocks. It’s available as a prefilled syringe that has 250 mg of Faslodex in 5 mL of solution. Usually, a dose of Faslodex is two syringes (500 mg total).

Dosage for breast cancer

Faslodex will be given at a doctor’s office. Usually, you’ll receive two injections (one in each buttock muscle) each time you go for a dose of Faslodex. The typical dose is 500 mg (two injections of 250 mg).

When you start treatment, you’ll receive doses on day 1, day 15, and day 29 in the first month. After the first three doses, you’ll only need Faslodex injections once per month.

If you have other medical conditions such as liver failure, your doctor may decrease your dose of Faslodex. Talk with your doctor about any medical conditions that you have before starting Faslodex.

What if I miss a dose?

Faslodex is given as an injection by your doctor or a healthcare professional. The doctor’s office or clinic where you receive injections will work with you to make sure the injection appointments fit your schedule. To help make sure you don’t miss an appointment, try setting a reminder on your phone.

Will I need to use this drug long term?

Faslodex is meant to be used as a long-term treatment. It’s typically used until the cancer gets worse or spreads further. If you and your doctor determine that Faslodex is safe and effective for you, you’ll likely take it long term.

Alternatives to Faslodex

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

Alternatives for HR-positive breast cancer

Following are examples of other drugs that may be used to treat HR-positive breast cancer.

For postmenopausal females:

• tamoxifen (Soltamox)
• anastrozole (Arimidex)
• exemestane (Aromasin)
• letrozole (Femara)

For premenopausal females:

• goserelin (Zoladex)
• leuprolide acetate (Lupron Depot)
• tamoxifen (Soltamox)

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

Faslodex vs. Femara

You may wonder how Faslodex compares with other medications that are prescribed for similar uses. Here we look at how Faslodex and Femara are alike and different.

Ingredients

The active ingredient in Faslodex is fulvestrant. The active ingredient in Femara is letrozole.

Uses

Faslodex is approved to treat hormone receptor-positive (HR-positive) breast cancer in the following situations:

• In postmenopausal females with advanced breast cancer that got worse after previous hormone therapy. (This type of treatment works by blocking hormones that may be contributing to the growth of the cancer.)
• In postmenopausal females with HER2-negative advanced breast cancer who’ve never had hormone therapy before. (With HER2-negative cancer, the cancer cells don’t have abnormally high levels of a protein called HER2.)
• Along with ribociclib (Kisqali), in postmenopausal females with HER2-negative advanced or metastatic breast cancer who’ve never tried hormone therapy or whose breast cancer got worse after previous hormone therapy. (Metastatic cancer means it’s spread to other parts of the body.)
• Along with palbociclib (Ibrance) or abemaciclib (Verzenio), in females with HER2-negative advanced or metastatic breast cancer whose breast cancer got worse after hormone therapy.

Femara is approved for use in postmenopausal females to:

• prevent HR-positive early stage breast cancer from coming back after it’s been treated
• prevent early stage breast cancer from coming back after it’s been treated, after having taken tamoxifen (Soltamox) for 5 years
• treat HR-positive (or unknown) advanced breast cancer as a first or second treatment

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

Drug forms and administration

Faslodex comes as a medication that’s injected into the muscles of the buttocks. You’ll receive Faslodex injections at a doctor’s office or clinic.

You’ll get Faslodex injections on days 1, 15, and 29 of your treatment. After the first three doses, you’ll get Faslodex injections once per month.

Femara is a tablet that’s taken by mouth. It’s usually taken once per day.

Side effects and risks

Faslodex and Femara have some similar side effects and others that differ. Below are examples of these side effects.

Mild side effects

These lists contain examples of mild side effects that can occur with Faslodex, with Femara, or with both drugs (when taken individually).

• Can occur with Faslodex:
  • pain at the injection site
  • pain in the arms or legs
  • low appetite that can lead to weight loss
• Can occur with Femara:
  • flushing
  • high cholesterol
  • excessive sweating
• Can occur with both Faslodex and Femara:
  • nausea
  • headache
  • edema (fluid buildup in the body)
  • dizziness
  • back pain
  • cough
  • shortness of breath
  • constipation
  • hot flashes
  • fatigue
  • bone and muscle pain

Serious side effects

These lists contain examples of serious side effects that can occur with Faslodex or with Femara.

• Can occur with Faslodex:
  • elevated liver enzymes (the level of these enzymes in your blood shows how well your liver is working)
  • bleeding
• Can occur with Femara:
  • low bone density

Effectiveness

These drugs haven’t been directly compared in studies. However, clinical trials have found both Faslodex and Femara to be effective for treating breast cancer.

A few clinical trials have looked at the combination of palbociclib (Ibrance) and Femara compared with the combination of palbociclib and Faslodex.

One trial is currently comparing these medications in people with HR-positive, HER2-negative metastatic breast cancer. Another trial compared these medications as the first treatment in HR-positive, HER2-negative advanced breast cancer. In this trial, both treatment options were found to be effective in treating breast cancer.

Costs

Faslodex and Femara are both brand-name drugs. There are generic forms of both drugs. Brand-name medications usually cost more than generics.

The actual price you’ll pay for any of these drugs depends on your insurance plan, your location, and the pharmacy you use.

Faslodex vs. Arimidex

You may wonder how Faslodex compares with other medications that are prescribed for similar uses. Here we look at how Faslodex and Arimidex are alike and different.

Ingredients

The active ingredient in Faslodex is fulvestrant. The active ingredient in Arimidex is anastrozole.

Uses

Faslodex is approved to treat hormone receptor-positive (HR-positive) breast cancer in the following situations:

• In postmenopausal females with advanced breast cancer that got worse after previous hormone therapy. (This type of treatment works by blocking hormones that may be contributing to the growth of the cancer.)
• In postmenopausal females with HER2-negative advanced breast cancer who’ve never had hormone therapy before. (With HER2-negative cancer, the cancer cells don’t have abnormally high levels of a protein called HER2.)
• Along with ribociclib (Kisqali), in postmenopausal females with HER2-negative advanced or metastatic breast cancer who’ve never tried hormone therapy or whose breast cancer got worse after previous hormone therapy. (Metastatic cancer means it’s spread to other parts of the body.)
• Along with palbociclib (Ibrance) or abemaciclib (Verzenio), in females with HER2-negative advanced or metastatic breast cancer whose breast cancer got worse after hormone therapy.

Arimidex is approved for use in postmenopausal females to:

• prevent HR-positive early stage breast cancer from returning after it’s been treated
• treat HR-positive (or unknown) metastatic or locally advanced breast cancer as the first treatment option (locally advanced means the cancer has spread only to areas close by, such as the skin or surrounding lymph nodes)
• treat advanced breast cancer in females whose cancer got worse after tamoxifen (Soltamox) treatment*

* Breast cancer that’s HR-negative or that didn’t respond to tamoxifen treatment usually does not respond to Arimidex.

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

Drug forms and administration

Faslodex comes as a medication that’s injected into the muscles of the buttocks. You’ll receive Faslodex injections at a doctor’s office or clinic.

You’ll get Faslodex injections on days 1, 15, and 29 of your treatment. After the first three doses, you’ll get Faslodex injections once per month.

Arimidex comes as an oral tablet that’s taken once per day.

Side effects and risks

Faslodex and Arimidex have some similar side effects and others that vary. Below are examples of these side effects.

Mild side effects

These lists contain examples of mild side effects that can occur with Faslodex, with Arimidex, or with both drugs (when taken individually).

• Can occur with Faslodex:
  • pain at the injection site
  • pain in the arms or legs
  • muscle pain
  • low appetite that can lead to weight loss
  • hair loss
• Can occur with Arimidex:
  • throat pain
  • high blood pressure
  • depression
  • bone fractures
  • insomnia
  • swollen lymph nodes
• Can occur with both Faslodex and Arimidex:
  • hot flashes
  • feeling weak
  • joint pain
  • nausea
  • vomiting
  • back pain
  • headache
  • cough
  • shortness of breath
  • fatigue

Serious side effects

These lists contain examples of serious side effects that can occur with Faslodex or with Arimidex.

• Can occur with Faslodex:
  • elevated liver enzymes (the level of these enzymes in your blood shows how well your liver is working)
  • bleeding
• Can occur with Arimidex:
  • osteoporosis
  • high cholesterol

Effectiveness

Faslodex and Arimidex have different FDA-approved uses, but they’re both used to treat certain types of breast cancer.

In a clinical trial, Faslodex was compared with anastrozole (Arimidex) for treating postmenopausal females with HR-positive, HER2-negative breast cancer. This study specifically looked at females with locally advanced or metastatic breast cancer who had never been treated for their breast cancer before. The trial found Faslodex to be slightly more effective than anastrozole for treating this type of cancer.

Faslodex was also studied in postmenopausal females with HR-positive breast cancer that had gotten worse after previous hormone therapy. This clinical trial compared Faslodex use with anastrozole use. This trial found Faslodex and anastrozole to be similarly effective for treating this type of cancer.

Costs

Faslodex and Arimidex are both brand-name drugs. There are generic forms of both drugs. Brand-name medications usually cost more than generics.

The actual price you’ll pay for either drug depends on your insurance plan, your location, and the pharmacy you use.

Common questions about Faslodex

Here are answers to some frequently asked questions about Faslodex.

Will I need to take other medications with Faslodex to treat or prevent bone problems?

Yes. Usually, people taking Faslodex should also take a medication to prevent bone loss, especially females who have already gone through menopause. This is because after menopause, you have a large decrease in the amount of estrogen in your body, which can cause bone loss.

In addition, medications used to treat your breast cancer will further lower your estrogen levels. This may increase your risk of bone loss. Medications such as zoledronic acid (Zometa) may be used along with Faslodex to prevent bone loss.

You may also need to take another medication if your breast cancer has spread into your bones. Denosumab (Xgeva) is used with chemotherapy to prevent and treat several types of bone problems in people with cancer.

Talk with your doctor about taking a medication to treat or prevent bone problems while you’re taking Faslodex.

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

Can Faslodex be used by males with breast cancer?

No, the Food and Drug Administration (FDA) has not approved Faslodex for use in males with breast cancer. It’s not known whether Faslodex is safe and effective for males with breast cancer because it hasn’t been studied in males.

FDA-approved treatments for males with breast cancer include tamoxifen (Soltamox) and palbociclib (Ibrance). However, your doctor may use Faslodex off-label to treat breast cancer in males. (Off-label use is when a drug that’s approved to treat one condition is used to treat a different condition.)

Talk with your doctor about the best way to treat your breast cancer.

Is Faslodex a chemotherapy drug?

No, Faslodex is not a chemotherapy drug. It’s a hormone therapy that works by decreasing the levels of certain hormones (estrogen and progesterone) in your body. These hormones cause your hormone receptor-positive (HR-positive) cancer to grow, so blocking them can help stop the spread of cancer or get rid of it completely.

I’ve had a mastectomy. Can I take Faslodex?

Yes, you can still take Faslodex if you’ve had a mastectomy (surgery to remove breast tissue). Even if your cancer didn’t spread outside the breast tissue, it’s still possible that some cancer cells escaped into your blood or lymph nodes. This can cause problems later on.

Faslodex lowers the amount of estrogen in your body, which stops HR-positive tumor cells from growing and multiplying. Taking Faslodex after a mastectomy helps lower your risk of the cancer spreading or coming back.

Your doctor can tell you whether Faslodex is a good treatment option for your breast cancer.

If I haven’t gone through menopause yet, will Faslodex affect my periods?

Yes, Faslodex may affect your periods if you haven’t gone through menopause yet. This is because Faslodex changes your hormone levels.

Faslodex decreases estrogen and progesterone levels in your body. These hormones are very important to the menstrual cycle. They help you ovulate, which causes your period to occur a few weeks later. Because your hormone levels will be affected, your period may become irregular or infrequent. In some females, it may stop completely.

Talk with your doctor if you have concerns about how Faslodex will affect your period.

Faslodex cost

The actual price you’ll pay for Faslodex depends on your insurance plan, your location, and the pharmacy you use.

It’s important to note that you’ll have to get Faslodex at a specialty pharmacy. This type of pharmacy is authorized to carry specialty medications. These are drugs that may be expensive or may require help from healthcare professionals to be used safely and effectively.

Your insurance plan may require you to get prior authorization before approving coverage for Faslodex. 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 whether your plan will cover Faslodex.

If you’re not sure whether you’ll need to get prior authorization for Faslodex, contact your insurance plan.

Financial and insurance assistance

If you need financial support to pay for Faslodex, or if you need help understanding your insurance coverage, help is available.

AstraZeneca, the manufacturer of Faslodex, offers a program called Access 360, which can help answer your questions about the cost of this drug. The manufacturer also offers the Faslodex Co-pay Savings Program, which can help lower the cost of the drug if you are eligible.

For more information about these programs, visit the manufacturer’s website.

How Faslodex works

Faslodex is approved to treat breast cancer that’s hormone receptor-positive (HR-positive).

What happens in HR-positive breast cancer

Breast cancer occurs when you develop a tumor in your breast from cells growing too quickly and out of control. With HR-positive breast cancer, the cancer is dependent on hormones, such as estrogen or progesterone, to grow and spread.

Estrogen causes two enzymes (a type of protein) within the cancer cells to become overactive. These enzymes are called cyclin-dependent kinases 4 and 6 (CDK 4 and 6).

CDK 4 and 6 help regulate how all cells grow and multiply. When they become overactive in cancer cells, they make the cancer cells grow and spread more rapidly.

What Faslodex does

Faslodex works by blocking estrogen from attaching to the estrogen receptors (docking stations) on your cells. Faslodex attaches itself to the receptors so that there isn’t a place for estrogen to attach to the cells. This prevents estrogen from stimulating the cancer cells to grow and multiply.

How long does it take to work?

It can take about 1 month (your first three doses) for Faslodex to begin effectively treating your breast cancer. You won’t be able to feel the effects of Faslodex in your body. However, your doctor should order tests during your treatment to check whether Faslodex is working for you.

Faslodex and alcohol

There are no known interactions between Faslodex and alcohol.

However, if you have alcohol-related liver disease (or liver disease from another cause), you may have to take a lower dose of Faslodex. This is because the usual dose may cause Faslodex to build up in your body.

If you drink alcohol, talk with your doctor about how much is safe to drink while you’re taking Faslodex.

Faslodex interactions

Faslodex is not known to interact with any medications. It’s also not known to interact with any supplements or foods. However, Faslodex can affect the results of certain lab tests.

Faslodex and other medications

There are no medications that are known to interact with Faslodex. However, it’s still important to go over the medications you’re taking with your doctor before starting Faslodex.

Before taking Faslodex, 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.

Faslodex and herbs and supplements

There aren’t any herbs or supplements that have been specifically reported to interact with Faslodex. However, you should still check with your doctor or pharmacist before using any of these products while taking Faslodex.

Faslodex and foods

There aren’t any foods that have been specifically reported to interact with Faslodex. If you have any questions about eating certain foods with Faslodex, talk with your doctor.

Faslodex and lab tests

Faslodex can affect the measurement of estrogen in your blood. This is because Faslodex is very similar to estrogen. Taking Faslodex can cause results from an estrogen blood test to be falsely high.

Estrogen can also be measured by urine tests or saliva tests. If you’re taking Faslodex and your doctor needs to check your estrogen levels, they may use a urine or saliva test (neither of which is affected by Faslodex) instead of a blood test.

Faslodex and pregnancy

Faslodex is not safe to take during pregnancy. This drug hasn’t been studied in pregnant females. However, in animal studies, fetuses of pregnant animals taking Faslodex had problems with bone growth and skeleton formation. Pregnant animals taking the drug also had a higher risk of miscarriage.

Because of this risk of harm to a fetus, you should use an effective method of birth control while taking Faslodex and for 1 year after your last dose of Faslodex.

If you are pregnant or planning to become pregnant, talk with your doctor before starting Faslodex. They will likely recommend a different treatment option for you.

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

Faslodex and birth control

It’s not safe to take Faslodex during pregnancy. If you’re sexually active and can become pregnant, talk with your doctor about your birth control needs while you’re using Faslodex.

You should take a pregnancy test within 7 days before starting Faslodex to ensure you aren’t pregnant. You’ll need to use birth control while taking Faslodex and for 1 year after your last dose.

Faslodex and breastfeeding

In most cases, you shouldn’t breastfeed while taking Faslodex and for 1 year after your last dose. It’s not known whether Faslodex is safe to take while breastfeeding and whether it passes into breast milk. However, in animal studies, Faslodex was present in the milk of lactating animals.

If you are currently breastfeeding or planning to do so, talk with your doctor before you start Faslodex treatment.