Avonex is a brand-name prescription medication. It’s FDA-approved to treat relapsing forms of multiple sclerosis (MS) in adults.

MS is a long-term condition that happens when your immune system mistakenly attacks the nerves in your brain and spinal cord. It causes inflammation (swelling) and scar tissue to develop around your nerve fibers. This makes it hard for your brain to communicate with the rest of your body. MS can have various symptoms, depending on which nerves are affected.

Most people with MS have a relapsing form of the disease. This means you get episodes of new symptoms or times when symptoms come back or get worse. Relapsing forms of MS that can be treated with Avonex include:

  • clinically isolated syndrome (one episode of symptoms that lasts at least 24 hours)
  • relapsing-remitting MS (periods of active disease that cause symptoms, followed by periods of remission where symptoms improve or go away completely)
  • active secondary progressive MS (when your MS is gradually getting worse all the time, but you still have relapses where your symptoms get noticeably worse for a while)

Avonex is a type of drug called a disease-modifying therapy. It helps slow down the progression of MS and reduce the number of relapses you have.

Avonex is given as an injection into a muscle once a week. Your doctor will teach you or your caregiver how to give the injections at home. The injection comes in three forms:

  • single-use prefilled autoinjector pen
  • single-use prefilled syringe
  • single-use vial of powder that you mix before giving the injection

Effectiveness

In clinical studies of people with relapsing MS, Avonex was found to slow worsening disability (such as having trouble walking), reduce the number of relapses, and reduce the number of brain lesions (areas of nerve damage). In people with clinically isolated syndrome, Avonex was found to reduce the risk of having a second episode.

For more information about the effectiveness of Avonex, see the “Avonex for MS” section below.

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

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

Avonex contains the active drug interferon beta-1a. Another brand-name version of interferon beta-1a is available. It’s called Rebif. However, it can’t be substituted for Avonex.

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

For more information on the possible side effects of Avonex, 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 they have approved. If you would like to report to the FDA a side effect you’ve had with Avonex, you can do so through MedWatch.

Mild side effects

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

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

  • abdominal (belly) pain
  • reaction at the injection site, such as swelling, redness, or pain
  • bronchitis
  • chest pain
  • joint pain
  • hair loss
  • migraine
  • toothache

* occurred in more than 10% of people in clinical studies

** occurred in less than 10% of people in clinical studies

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 Avonex 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:

  • Heart failure. Symptoms can include:
    • shortness of breath
    • swelling of your legs, ankles, or feet
    • sudden weight gain
  • Problems with your blood cells. Symptoms can include:
    • bruising or bleeding easily
    • fever
    • infections
    • feeling unusually weak or tired
  • Problems with your thyroid, such as an overactive or underactive thyroid. Symptoms can include:
    • feeling hot or cold
    • weight gain or weight loss
    • dry skin
    • fast or slow heartbeat
    • feeling restless, nervous, or shaky
    • feeling weak or tired
  • Seizures.

Other serious side effects are explained below in “Side effect details.” These 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 may cause.

Allergic reaction

As with most drugs, some people can have an allergic reaction after taking Avonex. It’s not known how often this occurs. Symptoms of a mild allergic reaction can include:

  • skin rash
  • itchiness
  • flushing (warmth and redness in your skin)

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

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

Depression

Changes in mood or behavior can occur while taking Avonex. Some people have experienced depression, suicidal thoughts, and other psychiatric symptoms.

In clinical studies, depression occurred in 18% of people who took Avonex, compared with 14% of people who took a placebo (a treatment with no active drug).

See your doctor right away if you have any changes in your mood or behavior while taking Avonex, such as:

  • feeling extremely sad or hopeless
  • thoughts of harming yourself or suicide
  • seeing or hearing things that aren’t really there
  • anxiety
  • irritability
  • aggression

Depression is common in people with MS, but it can usually be successfully treated with psychotherapy or antidepressant medication. You may need to stop using Avonex.

Suicide prevention

If you know someone at immediate risk of self-harm, suicide, or hurting another person:

  • Call 911 or the local emergency number.
  • Stay with the person until professional help arrives.
  • Remove any weapons, medications, or other potentially harmful objects.
  • Listen to the person without judgment.

If you or someone you know is having thoughts of suicide, a prevention hotline can help. The National Suicide Prevention Lifeline is available 24 hours a day at 1-800-273-8255.

Liver damage

Some people may have problems with their liver while taking Avonex. It’s not known how often this occurs. Liver failure has been reported in rare cases.

While you’re taking Avonex, you’ll need to have regular blood tests to check how well your liver is working. You may have a higher risk for liver problems if you drink alcohol or take other medications that can affect your liver.

See your doctor right away if you get any symptoms of a liver problem while you’re taking Avonex. These include:

  • nausea and vomiting
  • loss of appetite
  • feeling unusually weak or tired
  • upper right abdominal (belly) pain
  • unusually dark urine or pale stools
  • bleeding more easily than usual
  • jaundice (yellowing of your skin or whites of your eyes)

Flu-like symptoms

Avonex may cause flu-like symptoms, such as fever, chills, aching muscles, and feeling weak. These symptoms may start within a few hours or days after your injection and can last for about a day. They tend to be worse when you first start treatment.

In clinical studies of Avonex, flu-like symptoms occurred in 49% of people who took Avonex, compared with 29% of people who took a placebo.

Your doctor will usually start you on a low dose of Avonex that’s gradually increased over 4 weeks. This allows your body to get used to the medication and can help minimize flu-like side effects.

You can also relieve flu-like symptoms by taking an over-the-counter pain and fever reliever on your injection days. Examples include acetaminophen (Tylenol) and ibuprofen (Advil, Ibu-Tab, Motrin). Ask your pharmacist to recommend one of these drugs for you.

Many people find that they get fewer or no flu-like symptoms once they’ve been using Avonex for a while. However, talk with your doctor if you’re concerned about this side effect.

Hair loss

Hair loss can be a side effect of using Avonex. In clinical studies, hair loss occurred in 4% of people who took Avonex. In comparison, it occurred in 2% of people who took a placebo.

Talk with your doctor if you’re concerned about hair loss with Avonex.

Weight gain and weight loss (not side effects)

Weight changes were not reported in people who took Avonex in clinical studies. Weight changes have been seen in people taking other forms of interferon beta (the active drug in Avonex).

Tell your doctor if your weight changes while you’re using Avonex, because this could be a sign of more serious side effects. For example, suddenly gaining a lot of weight could be a symptom of fluid retention caused by heart failure.

Gradual weight gain can also be a sign of an underactive thyroid gland. On the other hand, weight loss can be a symptom that your thyroid gland has become overactive.

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

Avonex is FDA-approved to treat relapsing forms of multiple sclerosis (MS) in adults.

MS is a long-term condition that happens when your immune system mistakenly attacks the nerves in your brain and spinal cord. It causes inflammation (swelling) and scar tissue to develop around your nerve fibers. This makes it hard for your brain to communicate with the rest of your body. MS can have various symptoms, depending on which nerves are affected.

Most people with MS have a relapsing form of the disease. This means you get episodes of new symptoms or times when symptoms come back or get worse. Relapsing forms of MS that can be treated with Avonex include:

  • clinically isolated syndrome (one episode of symptoms that lasts at least 24 hours)
  • relapsing-remitting MS (periods of active disease that cause symptoms, followed by periods of remission where symptoms improve or go away completely)
  • active secondary progressive MS (when your MS is gradually getting worse all the time, but you still have relapses where your symptoms get noticeably worse for a while)

Avonex is a type of drug called a disease-modifying therapy. It helps to slow down the progression of MS and reduce the number and severity of relapses you have.

Effectiveness for MS

In clinical studies of people with relapsing MS, Avonex was found to slow the progression of disability, reduce the number of relapses, and reduce brain lesions (areas of nerve damage). Avonex treatment was compared with a placebo (a treatment with no active drug).

After 2 years, 22% of people who took Avonex had worsening disability (such as having trouble walking), compared with 35% of people who took a placebo. The people who took Avonex were 37% less likely than people who took a placebo to have their physical disability get worse.

Of the people who took Avonex for 2 years, 38% had no relapses. Of the people who took a placebo for 2 years, 26% had no relapses.

A second study looked at the effect of Avonex in people with clinically isolated syndrome. Researchers found that people who took Avonex were about half as likely as people who took a placebo to have a second episode within 3 years.

Avonex and children

Avonex is not approved for use in children. However, it’s sometimes used off-label to treat MS in children.

Research has shown that interferon beta (the active drug in Avonex) can slow the progression of disability, reduce the number of relapses, and reduce brain lesions in children.

It’s recommended that you take an over-the-counter pain and fever reliever on the days you have your Avonex injection. This can relieve the flu-like symptoms that commonly occur with Avonex. Examples of these drugs include acetaminophen (Tylenol) or ibuprofen (Advil, Ibu-Tab, Motrin). Ask your pharmacist to recommend one of these drugs for you.

If your multiple sclerosis (MS) relapses during treatment, you might be prescribed other drugs to take with Avonex. A relapse is when you get new or worsening MS symptoms. Other medications you may take include corticosteroids to reduce the nerve inflammation (swelling), as well as other drugs to treat specific symptoms.

Typically, your doctor will start you on a low dosage. Then they’ll 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 take the dosage your doctor prescribes for you. Your doctor will determine the best dosage to fit your needs.

Drug forms and strengths

Avonex comes in three forms for injection:

  • single-use prefilled autoinjector pen
  • single-use prefilled syringe
  • single-use vial of powder that you mix before giving the injection

Avonex comes in one strength: 30 micrograms (mcg).

Dosage for MS

The dosing frequency for Avonex is once a week. You should have your injection on the same day each week.

When you begin treatment, your doctor may start you on a low dose of Avonex. This helps to minimize flu-like symptoms that can be a side effect of the injections. The dose is gradually increased over 4 weeks to help your body get used to the medication.

The recommended starting dosage schedule for Avonex is as follows:

  • week 1: 7.5 mcg (1/4 dose)
  • week 2: 15 mcg (1/2 dose)
  • week 3: 22.5 mcg (3/4 dose)
  • week 4: 30 mcg (full dose)

When you start treatment, you’ll use Avonex prefilled syringes with an Avostartgrip titration kit. The titration kit contains three devices that you use to give the first three doses.

The full dosage of Avonex is typically 30 mcg once a week.

What if I miss a dose?

If you don’t have your Avonex injection on your usual day, you should have it as soon as possible that week. Then continue with your usual schedule the following week.

However, do not take Avonex 2 days in a row. If you miss a dose and don’t remember until just before you’re supposed to take your next dose, call your doctor to ask what to do.

To help make sure 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?

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

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

Examples of drugs other than Avonex that may be used to treat MS include:

  • corticosteroids to treat relapses, such as:
    • methylprednisolone (Medrol)
    • prednisone (Rayos)
  • disease-modifying therapies taken by mouth, such as:
    • siponimod (Mayzent)
  • disease-modifying therapies for self-injection, such as:
    • glatiramer acetate (Copaxone, Glatopa)
    • interferon beta-1a (Rebif)
    • interferon beta-1b (Betaseron, Extavia)
    • pegylated interferon beta-1a (Plegridy)
  • disease-modifying therapies given by drip into a vein, such as:
    • alemtuzumab (Lemtrada)
    • ocrelizumab (Ocrevus)

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

Ingredients

Avonex and Rebif both contain the drug interferon beta-1a.

Uses

Avonex and Rebif are both FDA-approved to treat relapsing forms of multiple sclerosis (MS) in adults. (A relapsing form means you get episodes of new symptoms or times when symptoms come back or get worse.)

Relapsing forms of MS that can be treated with Avonex and Rebif include:

  • clinically isolated syndrome (one episode of symptoms that lasts at least 24 hours)
  • relapsing-remitting MS (periods of active disease that cause symptoms, followed by periods of remission where symptoms improve or go away completely)
  • active secondary progressive MS (when your MS is gradually getting worse all the time, but you still have relapses where your symptoms get noticeably worse for a while)

Drug forms and administration

Avonex is taken by injection into a muscle once a week. It comes in three forms:

  • single-use prefilled autoinjector pen
  • single-use prefilled syringe
  • single-use vial of powder that you mix before giving the injection

Rebif is taken by injection under the skin three times a week. It comes in two forms:

  • single-use prefilled autoinjector (Rebidose)
  • single-use prefilled syringe

Side effects and risks

Avonex and Rebif 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 Avonex, with Rebif, or with both drugs (when taken individually).

  • Can occur with Avonex:
    • dizziness
    • nausea
    • hair loss
    • migraine
    • joint pain
    • body pain
    • toothache
  • Can occur with Rebif:
    • rash
    • sweating
    • abnormal vision
    • urinating often
    • back pain
    • bone pain
    • sleepiness
    • stiff muscles
  • Can occur with both Avonex and Rebif:
    • headache
    • flu-like symptoms, such as chills, fever, aching muscles, feeling weak
    • abdominal (belly) pain
    • chest pain
    • muscle pain
    • reaction at the injection site, such as swelling, redness, or pain

Serious side effects

This list contains examples of serious side effects that can occur with Avonex or with both drugs (when taken individually).

Effectiveness

The only condition both Avonex and Rebif are used to treat is relapsing forms of MS.

The use of Avonex and Rebif in treating relapsing-remitting MS has been directly compared in a clinical study. In this study, people who took Rebif were less likely to have a relapse of their MS than people who took Avonex. After 24 weeks treatment, 75% of people who took Rebif were relapse free compared with 63% of people who took Avonex.

Costs

Avonex and Rebif are both brand-name drugs. There are currently no generic forms of either drug. Brand-name medications usually cost more than generics.

According to estimates on GoodRx.com, Avonex generally costs less than Rebif. The actual price you’ll pay for either drug depends on your insurance plan, your location, and the pharmacy you use.

Avonex and Gilenya are prescribed for similar uses. Below are details of how these drugs are alike and different.

Ingredients

Avonex contains the active drug interferon beta-1a. Gilenya contains the active drug fingolimod. They are both disease-modifying therapies, but they work in different ways.

Uses

Avonex and Gilenya are both FDA-approved to treat relapsing forms of multiple sclerosis (MS). These include:

  • clinically isolated syndrome (one episode of symptoms that lasts at least 24 hours)
  • relapsing-remitting MS (periods of active disease that cause symptoms, followed by periods of remission where symptoms improve or go away completely)
  • active secondary progressive MS (when your MS is gradually getting worse all the time, but you still have relapses where your symptoms get noticeably worse for a while)

Avonex is only approved for use in adults. Gilenya is approved for use in adults and in children ages 10 years and older.

Drug forms and administration

Avonex is given by injection into a muscle once a week. It comes in three forms:

  • single-use prefilled autoinjector pen
  • single-use prefilled syringe
  • single-use vial of powder that you mix before giving the injection

Gilenya comes as capsules that you take by mouth once a day.

Side effects and risks

Avonex and Gilenya can cause some similar and some different side effects. Below are examples of these side effects.

Mild side effects

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

  • Can occur with Avonex:
    • reaction at the injection site, such as swelling, redness, or pain
    • chest pain
    • dizziness
    • joint pain
    • body pain
  • Can occur with Gilenya:
    • diarrhea
    • cough
    • shortness of breath
    • blurred vision
    • back pain
    • pain in your arms or legs
  • Can occur with both Avonex and Gilenya:
    • headache
    • flu-like symptoms, such as chills, fever, aching muscles, feeling weak
    • abdominal (belly) pain
    • nausea
    • migraine
    • hair loss

Serious side effects

These lists contain examples of serious side effects that can occur with Avonex, with Gilenya, or with both drugs (when taken individually).

  • Can occur with Avonex:
    • heart failure
  • Can occur with Gilenya:
    • slow heartbeat and heart block (when the signal that controls the heartbeat is blocked)
    • increased risk of infections
    • macular edema (swelling of the back of the eye)
    • posterior reversible encephalopathy syndrome (PRES), which causes swelling in your brain
    • breathing problems
    • raised blood pressure
    • severe worsening of disability (such as having trouble walking) after stopping Gilenya
  • Can occur with both Avonex and Gilenya:
    • liver damage
    • seizures
    • problems with your blood cells

Effectiveness

The only condition both Avonex and Gilenya are used to treat is relapsing forms of MS.

The use of Avonex and Gilenya in treating relapsing-remitting MS has been directly compared in a clinical study. In this study, people who took Gilenya were less likely to have a relapse than people who took Avonex. After about 1 year of treatment, 83% of people who took Gilenya were relapse free, compared with 70% of people who took Avonex. People who took Gilenya also had fewer new brain lesions (areas of nerve damage) than people who took Avonex.

Costs

Avonex and Gilenya are both brand-name drugs. There are currently no generic forms of either drug. Brand-name medications usually cost more than generics.

According to estimates on GoodRx.com, Avonex generally costs less than Gilenya. The actual price you’ll pay for either drug depends on your insurance plan, your location, and the pharmacy you use.

You should take Avonex according to your doctor’s or healthcare provider’s instructions.

Avonex is given as an injection into a muscle. Your doctor will teach you or your caregiver how to prepare and inject Avonex.

You can find detailed instructions for using Avonex pen, prefilled syringe, and powder for injection on the manufacturer’s website. Talk with your doctor or pharmacist if you have questions on how to give the Avonex injection.

If you’re using Avonex prefilled syringe or pen, take it out of the refrigerator about 30 minutes before giving an injection. This allows it to warm up to room temperature. Don’t warm up Avonex in a microwave or in hot water.

Do not reuse Avonex prefilled syringes or needles.

What are the injection sites for Avonex?

If you’re using the Avonex pen, the injection should be given into the outer side of your upper thigh.

If you’re using the Avonex prefilled syringe or Avonex powder solution, the injection can be given into your thigh or upper arm.

Choose an area of skin that is not irritated, red, infected, bruised, or scarred.

Use a different place within these injection sites each time you inject Avonex. This will lower your risk for having a reaction at your injection site.

About 2 hours after you have an injection, check your injection site for redness, tenderness, or swelling. See your doctor if you get a bad reaction or a reaction that doesn’t clear up in a few days.

How often will I take Avonex?

You’ll have an injection of Avonex once a week, on the same day each week.

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

Avonex is used to treat relapsing forms of multiple sclerosis (MS). Relapsing means you have episodes of new symptoms or times when your symptoms come back or get worse.

What happens in MS

MS is a chronic (long-term) condition that’s caused by your immune system mistakenly attacking the nerves in your brain and spinal cord. When this happens, it creates inflammation (swelling) that damages the outer protective layer of the nerves, called the myelin sheath.

Damaged myelin makes it harder for messages to travel along the nerve fibers from your brain to the rest of your body. This can result in various symptoms, depending on which nerves are affected.

The episode of inflammation (also called an attack or relapse) can last for a few days or a few months.

Scar tissue then develops around your nerve fibers in the places where the myelin is damaged. These areas are called lesions (areas of nerve damage) and can be seen on an MRI scan. The lesions also make it hard for messages to travel along the nerves.

With relapsing forms of MS, you have periods of time when your symptoms get better. This is called remission. It happens because your nerve cells repair themselves or make new pathways around the areas of damage. Periods of remission can last from a few months up to a few years.

However, over time the disease tends to get progressively worse, as new episodes of inflammation (swelling) damage different nerve cells. This can lead to increasing symptoms and disabilities (such as having trouble walking).

What Avonex does

Avonex is a type of drug called a disease-modifying therapy. It contains the active drug interferon beta-1a.

Interferons are protein molecules that are naturally produced by your immune system. There are many different types of interferons with various functions. They affect how your immune system works. Interferon beta-1a is a synthetic copy of one of these proteins.

It’s not fully understood how Avonex works in MS. However, it’s thought that Avonex modifies your immune system in some way to stop it from attacking your nerves.

When taken regularly, Avonex can help you have fewer episodes of inflammation (attacks or relapses). It also reduces the number of lesions in your brain. It slows the progression of the disease and how quickly any disability gets worse.

How long does it take to work?

It’s not known exactly how Avonex works, so it’s hard to say how long it takes to work.

Avonex helps prevent future relapses, rather than relieving existing symptoms. Therefore, it’s unlikely that you’ll notice when it starts working.

When you get Avonex from the pharmacy, the expiration date with be printed on the packaging, as well as on the pen, syringe, or vial.

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, talk to your pharmacist about whether you might still be able to use it.

Storage

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

Refrigeration

Store Avonex vials, prefilled syringes, and pens in the refrigerator. The storage temperature should be 36°F to 46°F (2°C to 8°C). Do not freeze Avonex. Store the vial, syringe, or pen in its original packaging to protect it from light.

If you’re using the Avonex prefilled syringe or pen, take it out of the refrigerator about 30 minutes before giving an injection. This allows it to warm up to room temperature. Don’t warm up Avonex in a microwave or in hot water.

How long can Avonex be unrefrigerated?

If needed, you can keep Avonex prefilled syringes and pens at room temperature (no higher than 77°F/25°C) for up to 7 days.

Avonex vials can be kept at room temperature (no higher than 77°F/25°C) for up to 30 days.

Disposal

You should dispose of used needles and syringes in a special sharps container.

If you no longer need to take Avonex 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.

You may be more at risk for liver damage if you drink alcohol while taking Avonex. If you drink alcohol, talk with your doctor about how much is safe for you to drink.

There are no known interactions between Avonex and any other medications, herbs and supplements, or foods.

Avonex and other medications

No medications have been specifically reported to interact with Avonex. However, before taking Avonex, 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.

Avonex and herbs and supplements

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

Avonex and foods

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

Avonex has not been studied in pregnant women, and it’s not known if it’s safe to using during pregnancy. Talk with your doctor before starting Avonex if you are pregnant or planning a pregnancy.

While using Avonex, see your doctor right away if you think you could be pregnant.

It’s not known if Avonex is safe to take 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 Avonex.

It’s not known if Avonex passes into breast milk. If you’re breastfeeding or plan to breastfeed, talk with your doctor about the risks and benefits of taking Avonex.

As with all medications, the cost of Avonex 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’ll have to get Avonex 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 Avonex. 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 Avonex.

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

Financial and insurance assistance

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

Biogen, the manufacturer of Avonex, offers a support program called Above MS. For more information about ways to save on Avonex and to find out if you’re eligible for financial assistance, call 800-456-2255 or visit the program website.

Here are answers to some frequently asked questions about Avonex.

Can I get a flu shot if I’m taking Avonex?

Yes, an annual flu vaccine is recommended in current guidelines for people with MS. It’s safe to get inactivated vaccines like the flu shot while you’re taking Avonex. (Inactivated vaccines contain killed bacteria or viruses. They can’t cause infections.)

Talk with your doctor about the best time to get the flu vaccine. If you’re having a relapse, it’s usually recommended that you wait until the relapse ends before getting a vaccine.

Live vaccines are not generally recommended for people who’re treating their MS with a disease-modifying therapy, such as Avonex. (Live vaccines contain live but weakened forms of viruses or bacteria. They have a small risk of causing infection in people with a very weak immune system.) The nasal spray flu vaccine is a live vaccine, so you shouldn’t get this form of the flu vaccine while taking Avonex.

Note: Getting a flu shot won’t prevent the flu-like symptoms that are a common side effect of Avonex injections. That’s because the vaccine helps to prevent flu infections. The flu-like symptoms that you can get with Avonex are not caused by a flu infection.

Is Avonex a steroid?

No, Avonex is not a steroid. It’s a type of drug called a disease-modifying therapy. It helps to slow down the progression of MS and reduce relapses.

Steroids reduce inflammation (swelling) and are prescribed to help treat symptoms. They reduce the inflammation of the nerves that are causing MS symptoms. However, they don’t slow down the long-term progression of the disease like Avonex does.

Will Avonex cure my MS?

No, there’s currently no cure for MS. However, Avonex can slow the progression of the disease. It can help you have fewer relapses and reduce the number of lesions (damaged areas) in your brain. It slows down the development of disabilities (such as having trouble walking).

I’m over the age of 65. Can I still use Avonex?

Yes you can, although clinical studies of Avonex didn’t include many people from this age group. Therefore, it’s not known if the drug will be as effective for you as it is for younger people. It’s also not known if you’re more likely to get side effects.

Talk with your doctor if you’re over the age of 65 and are interested in using Avonex.

Can I take Avonex if I’m being treated for depression?

Possibly, but this is something you should discuss with your doctor. Some people taking Avonex have developed depression. If you already have depression, it’s possible that taking Avonex could make it worse.

However, one review of studies didn’t find a clear relationship between depression and drugs that contain interferon beta (the active drug in Avonex). People who’d had depression in the past were more at risk for depression in the first 6 months of taking interferon compared with people without this history. However, the risk wasn’t raised enough to conclude that these people shouldn’t take interferon beta at all.

If you do take Avonex while being treated for depression, it’s very important to see your doctor right away if you feel your depression is getting worse. The same is true if you experience any other changes in your mood or behavior, such as extreme sadness or hopelessness, anxiety, irritability, aggression, hallucinations, or paranoia.

Will I get any side effects when I stop taking Avonex?

It’s not likely. Stopping Avonex is not known to cause any specific side effects. You don’t need to stop taking it gradually as you would with a drug that causes withdrawal symptoms.

If you stop treatment with Avonex, the most likely effect would be that your MS could start to get worse.

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

  • Allergy to interferon beta, or to any other ingredient of Avonex. Don’t take Avonex if you’ve had an allergic reaction to any of its ingredients in the past, or if you’ve ever had an allergic reaction to any other drugs containing interferon beta. Don’t use Avonex vials if you’re allergic to human albumin (a protein found in the blood).
  • History of depression or other psychiatric illness. Avonex can sometimes cause or worsen depression or other psychiatric symptoms. If you have a history of depression or other mental health issues, talk with your doctor about whether Avonex is right for you.
  • Liver problems. Avonex can sometimes cause or worsen liver problems. If you have an existing problem with your liver, your doctor will decide if Avonex is right for you.
  • Heart problems, such as heart failure. Avonex can sometimes cause or worsen heart failure. See your doctor right away if you get symptoms of new or worsening heart failure. These can include shortness of breath, or swelling of your legs, ankles, or feet.
  • Low numbers of red blood cells, white blood cells, or platelets in your blood. Avonex can sometimes cause or worsen problems with your blood cells. You’ll have regular blood tests to monitor your blood cells while you take Avonex.
  • History of seizures. Avonex can sometimes cause seizures. It’s not known if Avonex increases your risk for seizures if you’ve had one in the past.
  • Thyroid problems. Avonex can sometimes cause or worsen thyroid problems. If you have an overactive or underactive thyroid, you’ll have blood tests to monitor your thyroid hormones while you take Avonex.
  • Pregnancy. It’s not known if Avonex is safe to use during pregnancy. For more information, see the “Avonex and pregnancy” section above.
  • Breastfeeding. It’s not known if Avonex passes into breast milk. For more information, see the “Avonex and breastfeeding” section above.

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

Do not use more Avonex than your doctor recommends.

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 the American Association of Poison Control Centers at 800-222-1222 or use their online tool. But if your symptoms are severe, call 911 or go to the nearest emergency room right away.

The following information is provided for clinicians and other healthcare professionals.

Indications

Avonex is FDA-approved to treat relapsing forms of multiple sclerosis (MS) in adults. These include:

Mechanism of action

Avonex contains interferon beta-1a, produced using recombinant DNA technology. The sequence of amino acids in Avonex interferon beta-1a is identical to the sequence in natural human interferon beta.

The way interferon beta-1a works in MS is not understood. However, interferons are known to modulate the activity of the immune system. Avonex has been shown in clinical studies to reduce relapse frequency and number of brain lesions and to delay progression of disability in relapsing-remitting MS. It delays secondary episodes in those with clinically isolated syndrome.

Pharmacokinetics and metabolism

After a single intramuscular dose of Avonex, maximum serum levels are reached at around 15 hours. Biological markers of response (neopterin and β2-microglobulin) increase within 12 hours post-dose and reach maximum levels at around 48 hours post-dose. However, it’s not known what effect, if any, these markers have on disease activity.

The elimination half-life of Avonex is approximately 19 hours.

Contraindications

Avonex should not be used in people with known hypersensitivity to any ingredient, or to natural or recombinant interferon beta.

The vial form of Avonex should not be used in people with known hypersensitivity to human albumin.

Storage

Avonex vials, prefilled syringes, and pens should be stored in a refrigerator at 36°F to 46°F (2°C to 8°C). Do not freeze Avonex.

Avonex prefilled syringes and pens can be kept at room temperature (no higher than 77°F/25°C) for up to 7 days.

Avonex vials can be kept at room temperature (no higher than 77°F/25°C) for up to 30 days.

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 other 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.