Raloxifene

Introduction

Written by Alex Brewer, PharmD, MBA
Medically reviewed by Brittany A Duke, PharmD RPh
Updated on August 16, 2023

Raloxifene (ral OKS i feen) is a generic medication prescribed for helping to prevent and treat osteoporosis and for lowering the risk of breast cancer in certain people. Raloxifene belongs to a group of drugs called selective estrogen receptor modulators.

The Food and Drug Administration (FDA) has approved raloxifene to:

• help prevent and treat osteoporosis in females* who have gone through menopause
• lower the risk of invasive breast cancer in females who have gone through menopause and either have osteoporosis or are at high risk of invasive breast cancer

* Sex and gender exist on spectrums. In this article, we use the term “female” to refer to a person’s sex assigned at birth.

Boxed warning: Risk of blood clots and death from stroke

Raloxifene has a boxed warning about the risk of blood clots and death from stroke. Boxed warnings are the most serious warnings from the FDA.

For details, see the “Interactions and warnings for raloxifene” section.

Side effects of raloxifene

Raloxifene may cause mild or serious side effects. More common mild side effects of raloxifene and its serious side effects are listed below. This article doesn’t include all possible side effects of the drug. Side effects can vary based on your age, overall health, and any other medications you take.

To learn more about raloxifene’s side effects, ask your doctor or pharmacist. You can also refer to the prescribing information for raloxifene listed in the “Resources” section.

Mild side effects

More common mild side effects reported with raloxifene are listed below.

This article doesn’t include all possible mild side effects of the drug. To learn more about raloxifene’s side effects, refer to the prescribing information for raloxifene listed in the “Resources” section.

With many drugs, mild side effects may go away within a few days or a couple of weeks. If the side effects bother you, tell your doctor or pharmacist. They may be able to suggest ways to manage them.

Raloxifene oral tablet’s mild side effects include:

• hot flashes
• leg cramps
• swelling due to fluid retention in your ankles, feet, or legs
• flu-like symptoms, such as a cough or stuffy nose
• mild allergic reaction*

* For details about this side effect, see the “Interactions and warnings for raloxifene” section.

Serious side effects

Serious side effects of raloxifene are listed below.

This article doesn’t include all possible serious side effects of the drug. To learn more about raloxifene’s side effects, refer to the prescribing information for raloxifene listed in the “Resources” section.

With many drugs, serious side effects are possible but not common. If you have serious side effects from this drug, call your doctor right away. If you’re having severe symptoms or a medical emergency, call 911 or a local emergency number.

In general, raloxifene’s serious side effects include:

• boxed warning: risk of blood clots and death from stroke*
• severe allergic reaction*

* For details about this side effect, see the “Interactions and warnings for raloxifene” section.

Common questions about raloxifene

Below you’ll find answers to a few commonly asked questions about raloxifene.

How does raloxifene compare with tamoxifen?

Raloxifene and tamoxifen have some similarities, as well as some differences. Both drugs may be prescribed to lower the risk of invasive breast cancer in certain females.*

But these drugs have different uses as well. For example, raloxifene is prescribed to help prevent and treat osteoporosis in females who have gone through menopause. Tamoxifen is not approved for this use. And unlike raloxifene, tamoxifen may be prescribed to treat breast cancer in certain situations.

Talk with your doctor or pharmacist if you’d like to learn more about how raloxifene and tamoxifen compare.

* Sex and gender exist on spectrums. In this article, we use the term “female” to refer to a person’s sex assigned at birth.

What is raloxifene’s mechanism of action? How does the drug work?

Raloxifene belongs to a group of drugs called selective estrogen receptor modulators. It works differently in different parts of the body:

• In bone tissue, raloxifene intensifies the actions of estrogen. This helps strengthen bones and lowers the risk of a bone fracture.
• In breast tissue, raloxifene blocks the actions of estrogen. Some breast cancers are triggered to grow by estrogen, and raloxifene can block these signals.

You’re unlikely to “feel” the drug working, so talk with your doctor to learn more about when you might expect results from taking raloxifene. For example, it can take a few months before lab tests show raloxifene’s effects on strengthening bones.

If you’d like to know more about this, talk with your doctor or pharmacist.

Can raloxifene be used in males?

No, raloxifene is not approved for use in males.* The drug has not been studied in this population. It’s only approved for use in females* who have gone through menopause.

There are treatments for osteoporosis that are approved for use in males. Talk with your pharmacist or doctor to learn more about these treatment options.

* Sex and gender exist on spectrums. In this article, we use the terms “male” and “female” to refer to a person’s sex assigned at birth.

Will I experience certain side effects when stopping raloxifene?

No, it’s not expected. In studies of raloxifene, certain side effects weren’t noted when treatment with the drug was stopped.

That said, talk with your doctor before stopping treatment with raloxifene. If you stop taking raloxifene, your condition may worsen. Your doctor can review other treatments for your condition with you if you’re interested in stopping raloxifene.

Interactions and warnings for raloxifene

Below, you’ll find information about raloxifene’s possible interactions and warnings.

Interactions of raloxifene

Certain things may affect how a drug works. These include getting vaccines, consuming alcohol or certain foods, or taking the drug with other medications. This effect is called a drug interaction.

Before you take raloxifene, ask your doctor to check for possible interactions. Be sure to tell them about any of the following you take or use:

• prescription or over-the-counter drugs
• vitamins, herbs, or supplements

To learn about drug-condition interactions, see the “Warnings for raloxifene” section below.

Warnings for raloxifene

Some people should not take raloxifene, and others should take it cautiously.

Boxed warning: Risk of blood clots and death from stroke

Raloxifene has a boxed warning about the risk of blood clots and death from stroke. Boxed warnings are the most serious warnings from the Food and Drug Administration (FDA).

If you get a cut and have any bleeding, blood clotting is a normal process that stops you from losing too much blood. But if a blood clot forms inside your blood vessel, it doesn’t always dissolve on its own. If the clot moves through your bloodstream, it could get stuck (for example, inside your lungs) and stop blood from flowing.

This side effect was rarely reported in studies of raloxifene. According to these studies, this risk is highest during the first 4 months of treatment with raloxifene.

Symptoms of a blood clot vary depending on where the clot is. It’s possible to have a blood clot and not have any symptoms. But if a blood clot is in your:

• lungs (also called a pulmonary embolism, or PE), you may have difficulty breathing, feel severe chest pain, and cough up blood
• leg (also called a deep vein thrombosis, or DVT), you may have pain or tenderness, swelling, and skin that is warm to touch
• brain (also called a stroke), you may have difficulty speaking or understanding others, slurred speech, and numbness on one side of the face or body
• heart (also called a heart attack), you may have chest pain, left arm pain, and trouble breathing

If you have symptoms of a blood clot, seek immediate medical help. Call 911 or go to the closest emergency room, as this condition requires immediate treatment.

With stroke, a blood vessel in the brain bleeds. Or there’s a blockage of blood supply to the brain. This prevents oxygen from reaching your brain. Stroke was an uncommon side effect in studies of raloxifene. Taking the drug did not increase the risk of having a stroke.

But among people in one study who had a stroke, the risk of dying from the stroke was greater for those taking raloxifene. The people in this study also had coronary heart disease or other conditions that increased their risk of stroke.

Due to this risk, doctors usually won’t prescribe raloxifene if you’ve had a blood clot form in a vein in the past. To learn more, talk with your doctor or pharmacist.

Other warnings

Raloxifene could cause harm to people with certain health conditions. This effect is called a drug-condition interaction. Other factors can also affect whether raloxifene is a safe option for you.

Ask your doctor about specific warnings for raloxifene, and be sure to tell your doctor about your:

• current health, including any allergies to medications
• past health conditions or surgeries

Raloxifene can cause an allergic reaction in some people. Severe allergic reactions are rare but possible.

Allergic reaction

If you’ve had an allergic reaction to raloxifene or any of its ingredients, your doctor will likely not prescribe raloxifene. They can tell you about medications that are safer options for you.

A mild allergic reaction may cause the following symptoms:

• skin rash
• itchiness
• flushing (temporary warmth, redness, or deepening of skin color)

A severe allergic reaction may cause the following symptoms:

• swelling under your skin, usually in your hands, feet, eyelids, or lips
• swelling of your mouth, throat, or tongue, which can cause breathing problems

If you have an allergic reaction to raloxifene, call your doctor right away. If you have severe symptoms, call 911 or a local emergency number.

Overdose of raloxifene

You should not take more raloxifene than your doctor prescribes. For some drugs, doing so may lead to harmful effects or overdose.

If you think you’ve taken too much raloxifene, call your doctor or pharmacist right away. Or you could call 800-222-1222 to speak with someone at America’s Poison Centers. You can also use its online resource. If you have concerning symptoms, call 911 or a local emergency number immediately. You can also go to the closest emergency room.

Pregnancy or breastfeeding and raloxifene

Information about raloxifene and pregnancy and breastfeeding is described below.

Raloxifene and pregnancy

Raloxifene should not be taken during pregnancy. The drug is not approved for use in people who can become pregnant. If you’re planning a pregnancy or can become pregnant, talk with your doctor before taking this medication. Your doctor may suggest birth control options to use during treatment with raloxifene.

Raloxifene and breastfeeding

Raloxifene should not be taken while breastfeeding. The drug is not approved for use in people who can become pregnant. If you’re currently breastfeeding or planning to do so, talk with your doctor before taking this medication. Your doctor may recommend other ways to feed your child during treatment with raloxifene.

Uses of raloxifene

The Food and Drug Administration (FDA) approves prescription drugs such as raloxifene for certain conditions. Approved uses for raloxifene are described below.

Use for osteoporosis

Doctors may prescribe raloxifene oral tablet for helping to prevent and treat osteoporosis. It’s prescribed for this purpose in females* who have gone through menopause. It’s usually prescribed as a long-term treatment.

With osteoporosis, your bones lose strength and density. The outside of your bone also becomes thinner and weaker. This raises your risk of broken bones, even during routine activities like walking.

Osteoporosis often doesn’t cause symptoms. But it’s possible to have weakened grip strength, brittle nails, and receding gums in some cases.

Use for lowering the risk of breast cancer

Doctors may prescribe raloxifene oral tablet for lowering the risk of invasive breast cancer. It’s prescribed for this purpose in females* who have gone through menopause and either have osteoporosis or are at high risk of invasive breast cancer. It’s usually prescribed as a long-term treatment.

With invasive breast cancer, the cancer spreads beyond milk ducts or glands and into healthy breast tissue. (Most breast cancers are invasive.)

Invasive breast cancer may not cause symptoms in some cases. When symptoms are present, they can include a lump felt in the breast or armpit, changes in the shape or size of the breast, and fluid leaking from the nipples that isn’t breast milk.

Doctors may not prescribe raloxifene oral tablet in certain situations, such as for:

• treating invasive breast cancer or lowering the risk of it returning after treatment
• lowering the risk of noninvasive breast cancer

* Sex and gender exist on spectrums. In this article, we use the term “female” to refer to a person’s sex assigned at birth.

What to ask your doctor

Let your doctor know if you have questions about raloxifene or would like more details about it.

Here’s a list of some possible questions you may want to ask your doctor:

• How does raloxifene compare with other treatments for helping to prevent or treat osteoporosis?
• Does my health history raise my risk of side effects from taking raloxifene?
• Do any medications I take interact with raloxifene?
• How will we monitor and determine whether raloxifene is working for my condition?

Resources

• Food and Drug Administration. (2023). Orange Book: Approved drug products with therapeutic equivalence evaluations. https://www.accessdata.fda.gov/scripts/cder/ob/index.cfm
• Raloxifene hydrochloride – raloxifene hydrochloride tablet, film coated, tablets for oral use. (2021). https://nctr-crs.fda.gov/fdalabel/services/spl/set-ids/e8b6cbe0-c1f4-4678-b852-f629a7f6a1b5/spl-doc

Disclaimer: Optum Perks 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.