Rebif (interferon beta-1a)

Rebif generic or biosimilar

Rebif contains the active ingredient interferon beta-1a, which is a protein made by living cells. Because it’s made from living cells, Rebif is considered a biologic drug.

Rebif is available only as a brand-name medication. It’s not currently available in biosimilar form.

A biosimilar drug is a medication that’s similar to a brand-name biologic drug. A generic drug, on the other hand, is an exact copy of the active ingredient in a brand-name medication that’s made from chemicals. However, because biologic drugs are made from living cells, it’s not possible to copy these drugs exactly.

Rebif side effects

Rebif can cause mild or serious side effects. Here you’ll find some of the key side effects that may occur while using Rebif. The lists that follow do not include all possible side effects.

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

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. Sharing your experience helps make medications safer for everyone by giving doctors and researchers more information about how the drug works in real life. If you develop a side effect while taking Rebif and want to tell the FDA about it, visit MedWatch.

How long do side effects of Rebif last?

The most common side effects of Rebif are flu-like symptoms, such as muscle aches, tiredness, fever, and chills. For most people, these side effects either get better or go away over time. However, exactly how quickly the side effects go away is different for each person using the drug.

If you have questions about how long you may have certain side effects from Rebif, talk with your doctor.

And for more information about the flu-like symptoms caused by Rebif, see the “Side effect details” section.

Mild side effects

Mild side effects of Rebif can include:

• flu-like symptoms, such as muscle aches, headaches, tiredness, fever, and chills
• abdominal pain
• elevated liver enzymes
• injection site reactions
• fatigue
• fever

This is a partial list of mild side effects from Rebif. To learn about other mild side effects, talk with your doctor or pharmacist, or see Rebif’s prescribing information.

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

Serious side effects

Serious side effects from Rebif 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:

• Changes in the level of your blood cells, such as decreased levels of white blood cells, red blood cells, or platelets. Symptoms will vary depending on the blood cells affected, but they can include:
  • bleeding or bruising more easily than usual
  • increased risk of infection
• Seizures. Symptoms can include:
  • loss of consciousness
  • shaking or trembling
  • rapid eye movements
• Thrombotic microangiopathy, a rare condition that can cause life threatening blood clots in small blood vessels. Symptoms can include:
  • fatigue
  • bruising more easily than usual
  • excessive bleeding from small cuts or wounds, such as a paper cut
  • nosebleeds
  • confusion
  • urinating less than usual
• Pulmonary arterial hypertension (PAH). Symptoms can include:
  • chest pain
  • shortness of breath
  • dizziness or fainting
  • new or worsening fatigue

Other serious side effects, which are explained in more detail in the “Side effect details” section, include:

• allergic reaction
• severe injection site reactions
• liver problems, including liver damage
• depression or thoughts of suicide

Side effect details

You may wonder how often certain side effects occur with Rebif. Here’s some detail on some of the side effects this drug may cause.

Allergic reaction

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

• 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
• difficulty breathing

There have been reports of people having severe allergic reactions called anaphylaxis after receiving Rebif. However, it’s not known how common this type of allergic reaction is with the drug.

Keep in mind that even if you’ve been using Rebif for a long time, it’s still possible to have an allergic reaction to it.

Call your doctor right away if you have an allergic reaction to Rebif. But call 911 or your local emergency number if your symptoms feel life threatening or you think you’re having a medical emergency.

Injection site reactions, such as pain or necrosis

You may have reactions at your Rebif injection sites. These reactions can include pain and skin necrosis (death of skin cells). In Rebif’s clinical trials, injection site reactions included pain, skin discoloration, swelling, and abscesses (open wounds).

While using Rebif, if you have areas of skin that are discolored, swollen, or bruised, call your doctor right away. They’ll recommend treatment if needed. Also, you should avoid injecting Rebif into those areas until your doctor advises that you may.

While using Rebif, it’s important to reduce your risk of injection site infections and skin necrosis. Here are a few ways you can do so:

• Wash your hands before giving yourself each Rebif injection.
• Clean the area on your skin where you’ll be injecting the drug.
• Rotate your injection sites (inject in a different area of your body each time you administer Rebif).
• Never use a Rebif syringe or single-dose autoinjector for more than one injection.

Liver problems

Clinical trials have reported liver problems, including liver damage, in people using Rebif. In fact, changes in blood levels of liver enzymes are a common side effect of the drug. (Liver enzymes are certain types of proteins made by your liver.) In some cases, increased enzymes can be a sign of liver damage.

In rare cases, people who took Rebif required a liver transplant because of liver failure. However, it wasn’t reported how often this occurred during clinical trials.

Before and during Rebif treatment, your doctor may order blood tests to measure your liver enzyme levels. This allows your doctor to monitor the health of your liver and to make sure it’s safe for you to use Rebif.

Liver effects caused by Rebif can sometimes be serious. Because of this, it’s important to tell your doctor about any symptoms of liver problems you have while you’re receiving the drug. Symptoms may include:

• nausea
• loss of appetite
• feeling tired
• dark urine or pale stools
• jaundice
• excessive bleeding
• confusion

If you have any of these symptoms, call your doctor right away. They’ll determine whether or not you need medical attention.

Flu-like symptoms

You may experience flu-like symptoms during Rebif treatment. Flu-like symptoms were one of the more commonly reported side effects of Rebif in clinical trials.

Flu-like symptoms caused by Rebif may include:

• muscle aches
• fever or chills
• tiredness
• headache

If you have flu-like symptoms while receiving Rebif, talk with your doctor. They may recommend that you take over-the-counter pain or fever-reducing medications. These medications may include acetaminophen (Tylenol) or ibuprofen (Motrin). Both of these drugs can help reduce your flu-like symptoms.

For most people, flu-like symptoms caused by Rebif either get better or go away over time. However, exactly how long the symptoms last will be different for each person using Rebif.

Keep in mind that you may have an increased risk of infections during Rebif treatment. So if you have flu-like symptoms that are severe or don’t get better, call your doctor. They can check to ensure that you don’t have an infection, such as the flu.

Depression or thoughts of suicide

It’s possible to have mood changes while you’re receiving Rebif. Mood changes reported in clinical trials of Rebif include depression or thoughts of suicide or hurting yourself. It’s not known for sure how often these mood changes occur in people receiving the drug.

If you’ve had depression in the past, you have a higher risk of developing this side effect with Rebif. Also, keep in mind that depression is common in people with multiple sclerosis (MS), which Rebif is used to treat.

If you have feelings of hopelessness or depression, talk with your doctor as soon as possible. And if you have thoughts of hurting yourself or attempting suicide, call your doctor or 911 right away.

Rebif for MS

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

Rebif is FDA-approved for use in adults with certain forms of multiple sclerosis (MS). Specifically, Rebif is approved to treat the following conditions:

• Relapsing-remitting MS: With relapsing-remitting MS, there are times when you have either few MS symptoms or no MS symptoms, followed by periods of relapse. With relapse, you have new or worsened MS symptoms.
• Active secondary progressive MS: With active secondary progressive MS, your MS steadily gets worse over time. With this form of MS, you don’t have periods of relapse.
• Clinically isolated syndrome (CIS): CIS isn’t technically a form of MS. Instead, with CIS, you have an episode of MS-like symptoms that lasts at least 24 hours. CIS may or may not develop into MS.

With MS, your immune system attacks the protective covering, called the myelin sheath, around your nerve cells. This damage reduces communication between your brain and the nerves in the rest of your body.

It’s not known for sure what causes MS to develop. However, it’s thought that MS is caused by some sort of infection that triggers the immune system to overreact.

Over time, MS leads to lesions (areas of damage) in the brain and spinal cord. The condition can also cause certain disabilities, such as having difficulty walking or balancing.

Rebif contains the active ingredient interferon beta-1a, which is a protein that occurs naturally in the body. It’s not known exactly how Rebif works to treat MS. However, in clinical trials, the drug reduced MS symptom relapses and delayed disability caused by MS.

Effectiveness for MS

In clinical trials, Rebif was found to be safe and effective for treating relapsing-remitting MS, active secondary progressive MS, and CIS in adults. For information about these clinical trials, see the Rebif prescribing information.

Rebif and children

Rebif hasn’t been studied for use in children. So it’s not known whether the drug is safe or effective for use in people younger than 18 years of age.

Rebif use with other drugs

Your doctor may suggest that you take certain other drugs before injecting your doses of Rebif. Doing this may help reduce some of Rebif’s side effects, such as flu-like symptoms.

Flu-like symptoms caused by Rebif may include fevers, chills, and muscle aches. They may also include tiredness and headaches.

To help reduce flu-like symptoms, your doctor may recommend that you take an over-the-counter pain or fever-reducing medication. Examples include acetaminophen (Tylenol) and ibuprofen (Motrin).

If you’d like to know more about using other medications with Rebif, talk with your doctor.

Rebif cost

As with all medications, the cost of Rebif can vary.

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

It’s important to note that you may have to get Rebif 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.

If you have insurance, your insurance provider may require you to get prior authorization before it approves coverage for Rebif. This means that your doctor and insurance provider will need to communicate about your prescription before the insurance company will cover the drug. The insurance provider will review the request and let you and your doctor know whether your plan will cover Rebif.

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

Financial and insurance assistance

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

EMD Serono, Inc., the manufacturer of Rebif, provides financial support specialists who can help you find ways to reduce the cost of Rebif. For more information and to find out if you’re eligible for financial support, call 877-447-3243 or visit the program website.

Generic or biosimilar version

Rebif contains the active ingredient interferon beta-1a, which is a protein made by living cells. Because it’s made from living cells, Rebif is considered a biologic drug.

Rebif is available only as a brand-name medication. It’s not currently available in biosimilar form.

A biosimilar drug is a medication that’s similar to a brand-name biologic drug. A generic drug, on the other hand, is an exact copy of the active ingredient in a brand-name medication that’s made from chemicals. However, because biologic drugs are made from living cells, it’s not possible to copy these drugs exactly.

Usually, the generic or biologic form of a drug costs less than the brand-name form.

Alternatives to Rebif

Other drugs are available that can treat multiple sclerosis (MS) as well as clinically isolated syndrome (CIS). (CIS is a condition that causes MS-like symptoms.)

Some medications may be a better fit for you than others. If you’re interested in finding an alternative to Rebif, talk with your doctor. They can tell you about other medications that may work well for you.

Note: Some of the drugs listed here are used off-label to treat these specific conditions. (Off-label use is when a drug that’s approved to treat one condition is used to treat a different condition.)

Examples of other drugs that may be used to treat MS or CIS include:

• interferon beta-1a (Avonex)
• glatiramer acetate (Copaxone)
• ocrelizumab (Ocrevus)
• teriflunomide (Aubagio)
• interferon beta-1b (Betaseron)
• cladribine (Mavenclad)
• siponimod (Mayzent)
• fingolimod (Gilenya)
• peginterferon beta-1a (Plegridy)

Rebif vs. Avonex

You may wonder how Rebif compares with other medications prescribed for similar uses. Here, we look at how Rebif and Avonex are alike and different.

Ingredients

Both Rebif and Avonex contain the same active ingredient: interferon beta-1a. This drug is a type of protein that occurs naturally in your body.

Uses

Rebif and Avonex are both approved for use in adults with certain forms of multiple sclerosis (MS). Specifically, these drugs are approved to treat the following conditions:

• relapsing-remitting MS
• active secondary progressive MS
• clinically isolated syndrome (CIS)

For information about these conditions, see the “Rebif for MS” section.

Drug forms and administration

Rebif comes as a liquid solution. It’s available in single-dose, prefilled syringes. The syringes can be used with an optional autoinjector device to help make administering your injections easier. Rebif is also available in single-dose, prefilled devices called Rebif Rebidose autoinjectors.

Rebif is given by subcutaneous injection. It’s administered three times per week.

Avonex also comes as a liquid solution, and it’s available in both prefilled syringes and prefilled autoinjectors. Avonex is given by intramuscular injection. It’s administered once per week.

Side effects and risks

Rebif and Avonex both contain interferon beta-1a. Therefore, these medications can cause very similar side effects. Here you’ll find examples of these side effects.

Mild side effects

The following table lists the more common mild side effects that can occur with Rebif, with Avonex, or with both drugs (when used individually).

Serious side effects

The following table gives examples of serious side effects that can occur with Avonex or with both Rebif and Avonex (when used individually).

Effectiveness

The use of Rebif and Avonex in treating relapsing-remitting MS has been directly compared in a clinical trial. After 48 weeks:

• 62% of people who took Rebif were relapse-free. (With relapse, you have new or worsened MS symptoms.)
• 52% of people who took Avonex were relapse-free.

Also, this trial found that people who took Rebif had fewer brain or spinal cord lesions on MRI scans than people who took Avonex. MRI scans are imaging tests used to check for brain or spinal cord lesions in people with MS. And lesions on the brain or spinal cord indicate areas of damage.

Costs

Rebif and Avonex are both brand-name biologic drugs, which are made from living cells. There are currently no biosimilar forms of either drug. Brand-name biologic drugs usually cost more than biosimilars. (For more information, see the “Rebif generic or biosimilar” section.)

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

Rebif vs. Copaxone

Like Avonex (discussed in the previous section), other drugs are prescribed for uses that are similar to those of Rebif. Here, we look at how Rebif and Copaxone are alike and different.

Ingredients

Rebif contains the active ingredient interferon beta-1a. This is a type of protein that occurs naturally in your body.

Copaxone contains the active ingredient glatiramer acetate. This is a combination of four amino acids (building blocks used to make proteins).

Uses

Rebif and Copaxone are both approved for use in adults with certain forms of multiple sclerosis (MS). Specifically, these drugs are approved to treat the following conditions:

• relapsing-remitting MS
• active secondary progressive MS
• clinically isolated syndrome (CIS)

For information about these conditions, see the “Rebif for MS” section.

Drug forms and administration

Rebif comes as a liquid solution. It’s available in single-dose, prefilled syringes. The syringes can be used with an optional autoinjector device to help make administering your injections easier. Rebif is also available in single-dose, prefilled devices called Rebif Rebidose autoinjectors.

Rebif is given by subcutaneous injection. It’s administered three times per week.

Copaxone also comes as a liquid solution inside single-dose, prefilled syringes. It’s given by subcutaneous injection. Copaxone can be administered either once per day or three times per week, depending on the strength of the drug.

Side effects and risks

Rebif and Copaxone both contain drugs used to treat multiple sclerosis (MS). Therefore, these medications can cause very similar side effects. Here are examples of these side effects.

Mild side effects

The following table lists the more common mild side effects that can occur with Rebif, with Copaxone, or with both drugs (when used individually).

Serious side effects

The following table gives examples of serious side effects that can occur with Rebif, with Copaxone, or with both drugs (when used individually).

Effectiveness

The use of Rebif and Copaxone in treating relapsing-remitting MS has been directly compared in several clinical trials. And these studies were all evaluated together in one 2016 analysis.

The analysis showed that Copaxone and Rebif (as well as other interferon beta drugs similar to Rebif) were similarly effective in preventing MS relapses.

The analysis also showed that people who took Copaxone had slightly more MS lesions on MRI scans than people using other drugs, such as Rebif. MRI scans are imaging tests used to check for brain or spinal cord lesions in people with MS. And lesions on the brain or spinal cord indicate areas of damage.

Costs

Rebif and Copaxone are both brand-name drugs.

Rebif is a biologic drug, which is made from living cells. There are currently no biosimilar forms of this drug. Brand-name biologic drugs usually cost more than biosimilars. (For more information, see the “Rebif generic or biosimilar” section.)

Copaxone is available as a generic medication called glatiramer acetate. (Glatiramer acetate is the active ingredient in Copaxone.) Generic drugs usually cost less than their brand-name versions.

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

How to administer Rebif

You should administer Rebif according to your doctor’s or healthcare professional’s instructions.

Rebif is given as a subcutaneous injection. Your doctor will give you your first Rebif injection and show you how to administer the injections yourself. Then, you’ll be able to give yourself Rebif injections at home.

Rebif injection sites

The best places on your body to inject Rebif are areas where there’s a layer of fat between your skin and muscle. These areas are usually found on the:

• abdomen
• buttocks
• thighs
• outer part of your upper arm

If you have a low body weight, you should inject Rebif into your thigh or upper arm. There’s usually a bit more fat between your skin and muscle in these areas.

Regardless of your body weight, you should rotate your Rebif injection sites. That is, you should choose a different area to inject the drug each time you give yourself a dose of Rebif. This will help reduce your risk of scarring or skin irritation at the injection sites.

Don’t inject Rebif in any area of skin that looks discolored, bruised, infected, or irritated. Injecting into these areas could increase your risk of irritation or infection.

How to inject Rebif using single-dose, prefilled syringes

Rebif comes in single-dose, prefilled Rebidose autoinjectors and in single-dose, prefilled syringes. Here, we describe how to use the single-dose, prefilled syringes.

You can use Rebif prefilled syringes either alone or with devices called Rebiject II autoinjectors.

Using Rebif single-dose, prefilled syringes alone

When using Rebif syringes alone, administer the drug by following these steps:

1. Wash your hands thoroughly, and clean the injection site with alcohol.
2. Pinch the skin around the injection site to lift it up a bit.
3. Hold the syringe at a 90-degree angle from your skin. Use a quick, firm motion to insert the needle straight into your skin.
4. Once the needle is inserted, let go of the pinched skin and gently push the syringe plunger all the way down.
5. You can then remove the needle from your skin and gently apply pressure to the injection site with a clean cotton ball or gauze pad.
6. Dispose of the used syringe in a sharps container. Here are some tips on how to safely dispose of the syringe. Your doctor can also give you instructions for doing this.
7. Monitor your injection site for any discoloration or swelling.

For more detailed instructions, see the manufacturer’s website.

Using Rebif single-dose, prefilled syringes with a Rebiject II autoinjector

To use a Rebiject II autoinjector with a prefilled syringe, place the syringe into the autoinjector device. You can use the Rebiject II autoinjector for more than one dose of Rebif. Unlike the prefilled Rebidose autoinjector (discussed next), you don’t need to throw away the Rebiject II autoinjector after each use.

Using the autoinjector device with Rebif syringes can help make administering the drug a bit easier. This is because the autoinjector allows you to adjust the depth of the needle in your skin. And with the device, you’ll have a nonslip grip on the Rebif syringe. In addition, the autoinjector device has a signal that lets you know when your dose has been fully injected.

You can find detailed instructions on how to use the Rebiject II autoinjector device on the manufacturer’s website.

How to inject Rebif using single-dose, prefilled Rebidose autoinjectors

Rebif comes in single-dose, prefilled syringes and in single-dose, prefilled Rebidose autoinjectors. Here, we describe how to use the single-dose, prefilled Rebidose autoinjectors.

Rebif single-dose, prefilled Rebidose autoinjectors are fully assembled and ready to use. When using Rebidose autoinjectors, you can administer Rebif by following these steps:

1. Wash your hands thoroughly, and clean the injection site with alcohol.
2. Pull the needle cap off of the autoinjector and throw it away.
3. Hold the Rebidose autoinjector in your palm, with your thumb hovering above the injector button.
4. Place the autoinjector against your skin at a 90-degree angle and push it against your skin until you feel some resistance.
5. Use your thumb to push the injector button. You’ll hear a click, which indicates that the device has started injecting your dose of Rebif.
6. Keep the Rebidose autoinjector pressed against your skin for 10 seconds while the medication is being injected. Before removing the device from your skin, look to make sure that the device’s syringe plunger has moved all the way to the bottom. This means that your entire dose has been injected.
7. Lift the Rebidose autoinjector from your skin and dispose of the device using a sharps container.

For more detailed instructions on how to use the Rebidose autoinjector, visit the manufacturer’s website.

When to administer

You’ll give yourself Rebif injections three times per week.

It’s recommended that you inject the drug at the same time on each of your injection days. And it’s best to inject your doses either late in the afternoon or sometime in the evening. You should give yourself your dose on the same 3 days every week, making sure there are at least 48 hours between each of your Rebif injections.

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

Rebif dosage

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

• the type and severity of the condition you’re using Rebif to treat
• your age
• other medical conditions you may have
• whether or not you have side effects during Rebif treatment

Your doctor will start you on a low dosage and adjust it over time to reach the amount that’s right for you. 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, be sure to follow the dosing instructions your doctor prescribes for you. Your doctor will determine the best dosage to fit your needs.

Drug forms and strengths

Rebif comes as a liquid solution. It’s available inside single-dose, prefilled syringes. The syringes can be used with an optional autoinjector device to help make administering your injections easier. Rebif is also available in single-dose, prefilled devices called Rebif Rebidose autoinjectors.

Both Rebif prefilled syringes and Rebif Rebidose autoinjectors come in the following strengths, expressed in micrograms (mcg) per milliliter (mL).

• 8.8 mcg/0.2 mL
• 22 mcg/0.5 mL
• 44 mcg/0.5 mL

Rebif is given by subcutaneous injection. For more information about the different forms of Rebif and how each one is administered, see the “How to administer Rebif” section.

Dosage for MS

The typical dosage of Rebif for multiple sclerosis (MS) is either 22 mcg or 44 mcg injected three times per week. However, when you’re first starting Rebif, you’ll receive a lower dosage called a starting dosage.

For your starting dosage, your doctor will recommend that you give yourself either 4.4 mcg or 8.8 mcg three times per week. Your doctor will gradually increase your dosage every 2 weeks. If you follow this dosing schedule, you should reach your full dosage of Rebif on your fifth week of treatment.

What if I miss a dose?

If you miss a dose of Rebif, give yourself the missed dose as soon as you remember. Then, you should administer your next dose of Rebif 48 hours later. You should never give yourself more than two Rebif injections within a 48-hour period.

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?

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

Common questions about Rebif

Here are answers to some frequently asked questions about Rebif.

Does Rebif cause weight loss or weight gain?

Changes in weight, such as weight gain or weight loss, haven’t been reported as common side effects of Rebif. However, weight changes may be a sign of liver damage, which is a possible side effect of Rebif.

If you notice changes in your body weight during Rebif treatment, talk with your doctor right away. They can check to see whether your weight change is due to a condition that needs medical attention.

Are there any side effects of stopping Rebif?

No. If you stop Rebif treatment, you likely won’t have any side effects. However, your multiple sclerosis (MS) may flare up or worsen more quickly than it would if you continued treatment.

If you have questions about stopping Rebif, talk with your doctor. They can discuss with you the risks and benefits of stopping treatment.

Can Rebif cause PML?

It’s unlikely that Rebif will cause progressive multifocal leukoencephalopathy (PML). This is a rare brain infection that results from the John Cunningham (JC) virus. PML infections can be dangerous. They can lead to swelling in your brain and can even be fatal.

Most people already have the JC virus in their bodies. In people with a healthy immune system, the virus doesn’t cause any harm. However, in people with a weakened immune system, the virus can cause a PML infection.

Since Rebif’s approval for use, there have been rare cases of people developing PML while receiving interferon beta-1a. (Interferon beta-1a is the active ingredient in Rebif.) However, more research is needed to know for sure how often PML occurs in people receiving Rebif.

If you have concerns about developing PML while using Rebif, talk with your doctor. They can discuss with you the risks and benefits of treatment.

Will Rebif cure my condition?

No, it won’t cure your condition. In fact, at this time, there’s no known cure for MS.

Even though Rebif won’t cure your MS, it may help reduce the number of MS flare-ups you have. The drug may also help slow the development of physical disabilities caused by MS, such as difficulty walking.

If you’d like to know more about the benefits of using Rebif, talk with your doctor.

Is Rebif a steroid?

No, Rebif isn’t a steroid. Rebif is a type of protein that occurs naturally in your body. This medication contains the active ingredient interferon beta-1a.

It’s not known exactly how Rebif works to treat MS. However, the drug has been shown to help reduce MS symptom flare-ups. Rebif has also helped delay disability caused by MS.

Will I need to have lab tests done during Rebif treatment?

Yes, you’ll likely need to have certain tests done during Rebif treatment.

For example, your doctor will probably order certain blood tests to check your liver enzymes and blood cell counts. This is because Rebif may lower the level of certain blood cells in your body. The drug may also affect your liver and increase your liver enzymes. For more information about Rebif’s effect on your liver, see the “Rebif side effects” section.

Your doctor may also order an imaging test called an MRI scan. This test allows your doctor to monitor lesions in your brain or spinal cord. Lesions are areas of damage caused by MS.

If you have questions about the tests you may need during Rebif treatment, talk with your doctor.

Rebif storage

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

Both Rebif syringes and autoinjectors should be stored in the refrigerator. They should be kept at a temperature between 36°F and 46°F (2°C and 8°C). Rebif can be stored at this temperature until its expiration date. Do not freeze Rebif.

It’s also possible to store Rebif at a warmer temperature, as high as 77°F (25°C). However, if Rebif is stored out of the refrigerator at room temperature, it’s only good for 30 days. This is because the drug doesn’t contain any preservatives.

In either case, store the drug away from heat and light.

For find out how to safely dispose of Rebif, ask your doctor or pharmacist.

Rebif and alcohol

You should talk with your doctor before drinking alcohol while using Rebif. This is because both Rebif and alcohol may cause harm to your liver. And if you consume alcohol during Rebif treatment, your risk of liver problems can be significantly increased.

Before starting Rebif, tell your doctor if you regularly consume alcohol. Your doctor may check your liver enzymes (certain types of proteins) more frequently than usual during treatment. This allows your doctor to monitor the health of your liver.

If you have questions about the safety of drinking alcohol during Rebif treatment, talk with your doctor.

Rebif interactions

Rebif isn’t known to interact with any other medications, herbs, supplements, or foods.

However, before starting Rebif, talk with your doctor and pharmacist. Tell them about all prescription, over-the-counter, and other drugs you take. Also tell your doctor 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.

Rebif precautions

Before taking Rebif, discuss your health history with your doctor. Rebif may not be right for you if you have certain medical conditions or other factors affecting your health. Be sure to talk with your doctor if any of the following apply to you:

• depression or thoughts of suicide
• liver problems
• bleeding problems or a history of blood clots
• seizure disorder
• heart problems
• lung problems
• previous allergic reaction to this or a similar drug
• allergy to albumin
• pregnancy
• breastfeeding

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

Rebif and pregnancy, breastfeeding, and birth control

It’s not known whether Rebif is safe to use during pregnancy. There haven’t been any studies done involving pregnant people receiving the drug. It’s also not known whether Rebif is safe to use while breastfeeding.

If you’re sexually active and you or your partner can become pregnant, talk with your doctor about your birth control needs while using Rebif.

How Rebif works

Rebif is approved to treat certain forms of multiple sclerosis (MS). The drug is also approved to treat clinically isolated syndrome (CIS), which is a condition that causes MS-like symptoms. (Because MS and CIS affect your body in similar ways, these conditions are often discussed together.)

With MS, your immune system attacks the protective covering around your nerve cells, called the myelin sheath. This damage reduces the communication between your brain and the nerves in the rest of your body.

It’s not known for sure what causes MS. It’s thought that MS may result from some sort of infection that triggers your immune system to overreact.

Because the cause of MS isn’t known for sure, it’s hard to know exactly what Rebif’s mechanism of action is for treating the condition. (A drug’s mechanism of action is how it works.) However, the drug has been shown to reduce MS relapses and delay disability caused by the disease.

How long does it take to work?

Every person’s body is different, which means that MS affects each person differently. Some people have long periods without MS symptoms, while other people have shorter times between experiencing MS symptoms. In addition, the duration of MS flare-ups can vary for different people.

Rebif is used to help reduce MS symptom relapses and delay disability caused by the disease. However, because MS affects people differently, it’s not known for sure how long it will take for Rebif to work to treat your MS.

How can I tell if Rebif is working for me?

It might be difficult for you to tell whether Rebif is working to treat your MS. This is especially the case if you usually go long periods of time without having MS flare-ups.

Rebif helps to reduce MS symptom flare-ups and to delay disability caused by the disease. Over time, you should notice a reduction in the number of MS flare-ups you have.

If you’d like to know more about how you can tell whether Rebif is working for you, talk with your doctor.

Rebif overdose

Do not use more Rebif than your doctor recommends. For some drugs, receiving more than recommended may cause unwanted side effects or overdose.

What to do if you receive too much Rebif

If you think you’ve received 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. If your symptoms are severe, call 911 or go to the nearest emergency room right away.

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.