Generic Name: interferon-alfa-2b, Parenteral Solution

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SECTION 1 of 4

Highlights for interferon-alfa-2b

Parenteral Solution
1

Interferon alfa-2b is an injected drug used to treat certain blood and skin cancers, inflammation of your liver, or genital warts caused by human papillomavirus.

2

Your dose of interferon alfa-2b depends on your age and the condition that’s being treated.

3

Common side effects include flu-like symptoms, such as fever, headache, chills, muscle pain or weakness, or tiredness.

4

Interferon alfa-2b may cause or worsen mental health conditions or heart problems. It may also affect your immune system and increase your risk for developing infections.

IMPORTANT INFORMATION

FDA Warning

This drug has a Black Box Warning. This is the most serious warning from the Food and Drug Administration (FDA). A black box warning alerts doctors and patients to potentially dangerous effects.

Warning: Interferon alfa-2b may cause mental health conditions or heart problems. It may also affect your immune system and increase your risk for developing infections. If you have an existing mental health or heart issue or an active infection, it can make these problems worse. Your doctor may do tests to check for these conditions. You may need to stop taking interferon alfa-2b if this occurs.

Liver disease warning

Don’t use this medication if you have serious liver disease. It may further damage your liver, which could be fatal. Your doctor may take blood tests to make sure your liver is working well.

Blood cell count warning

Interferon alfa-2b can affect your bone marrow and lower your blood cell counts. If your blood cell counts become very low, you may get infections or have bleeding problems. Your doctor should monitor your blood cell levels.

Risk of infection

You may get an infection while taking interferon alfa-2b. Tell your doctor if you have symptoms such as:

  • fever
  • chills
  • bloody diarrhea
  • burning or pain when urinating
  • coughing up yellow or pink phlegm

Drug Features

Interferon alfa-2b is a prescription drug. It‘s available in these forms: powder for injection and liquid solution for injection.

You can give yourself the injection.

This drug may be used as part of a combination therapy. That means you need to take it with other drugs.

Why It's Used

Interferon alfa-2b is used to treat certain blood and skin cancers, inflammation of your liver, or genital warts caused by human papillomavirus.

More Details

How It Works

Interferon alfa-2b belongs to a class of drugs called interferons. It works with white blood cells in your body to help prevent viruses and abnormal cells from growing more. This keeps your condition from getting worse.

Why It's Used

Interferon alfa-2b is used to treat certain blood and skin cancers, inflammation of your liver, or genital warts caused by human papillomavirus.

It’s approved for:

  • hairy cell leukemia
  • after surgery for malignant melanoma, within 56 days of surgery
  • follicular non-Hodgkin’s lymphoma
  • human papilloma virus (HPV) infection
  • Kaposi’s sarcoma related to acquired immunodeficiency syndrome (AIDS) virus
  • chronic hepatitis C
  • chronic hepatitis B
SECTION 2 of 4

interferon-alfa-2b Side Effects

Parenteral Solution

Most Common Side Effects

The most common side effects that occur with interferon alfa-2b include:

  • fever

  • headache

  • chills

  • muscle weakness or pain

  • tiredness

Serious Side Effects

If you experience any of these serious side effects, call your doctor right away. If your symptoms are potentially life threatening or if you think you’re experiencing a medical emergency, call 9-1-1.

  • eye problems. Symptoms may include:

    • changes in vision
    • trouble seeing
    • blurred vision
  • lung problems. Interferon alfa-2b may lead to difficulty breathing, pneumonia, or other conditions affecting your lungs that may be fatal. Symptoms may include:

    • fever
    • cough
    • trouble breathing
  • inflammation of your pancreas. Symptoms may include high cholesterol and:

    • severe stomach pain
    • nausea
    • vomiting
    • severe back pain
    • fever
  • stroke. Symptoms may include:

    • weakness
    • numbness on your face, arm, or leg, or on one side of your body
    • loss of coordination
    • severe headache
    • trouble seeing or blurred vision in one or both eyes
    • slurred speech
    • problems understanding
    • confusion
  • changes in your mental health. Symptoms may include:

    • irritability
    • depression
    • getting angry or violent
    • returning to previous drug addictions
    • thoughts of hurting yourself or others
  • heart problems. Symptoms may include:

    • low blood pressure (feeling faint or dizzy)
    • abnormal heartbeat or rapid heartbeat
    • heart attack (chest pain, pain in your upper body including in one or both arms)
  • inflammation of your colon (colitis). Symptoms may include:

    • stomach pain
    • bloody diarrhea
    • fever
  • liver problems. Symptoms may include:

    • yellowing of your skin or the whites of your eyes
    • nausea and loss of appetite
    • diarrhea
    • tiredness and confusion
    • swelling of your stomach area
    • bleeding more easily
Pharmacist's Advice
Healthline Pharmacist Editorial Team

Interferon alfa-2b does not cause drowsiness.

Mild side effects may go away within a few days or a couple of weeks. If they’re more severe or don’t go away, talk to your doctor or pharmacist.

Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs affect each person differently, we cannot guarantee that this information includes all possible side effects. This information is not a substitute for medical advice. Always discuss possible side effects with a healthcare provider who knows your medical history.
SECTION 3 of 4

interferon-alfa-2b May Interact with Other Medications

Parenteral Solution

Interferon alfa-2b can interact with other medications, herbs, or vitamins you might be taking. That’s why your doctor should manage all of your medications carefully. If you’re curious about how this drug might interact with something else you’re taking, talk to your doctor or pharmacist.

Note: You can reduce your chances of drug interactions by having all of your prescriptions filled at the same pharmacy. That way, a pharmacist can check for possible drug interactions.

Medications That Might Interact with This Drug

Hepatitis B drug
  • telbivudine (Tyzeka)

Taking these drugs together may increase your risk of developing severe nerve pain in your arms and legs.

Human immunodeficiency virus (HIV) drugs
  • non-nucleoside reverse transcriptase inhibitors (NNRTIs). Examples include:
    • delavirdine
    • efavirenz
    • etravirine
    • nevirapine
    • rilpivirine
  • nucleoside reverse transcriptase inhibitors (NRTIs). Examples include:
    • abacavir
    • didanosine
    • emtricitabine
    • lamivudine
    • stavudine
    • tenofovir
    • zidovudine. Taking these drugs together may lead to higher levels of zidovudine in your body. This can cause greater side effects, such as lowering your blood counts.
  • protease inhibitors. Examples are:
    • atazanavir
    • darunavir
    • fosamprenavir
    • indinavir
    • lopinavir/ritonavir
    • nelfinavir
    • ritonavir
    • saquinavir
    • tipranavir

The combination of interferon alfa-2b and certain HIV drugs may lead to worse liver function.

Lung medication
  • theophylline

Taking these drugs together may lead to higher levels of theophylline in your body. This increases your risk of side effects such as nausea, vomiting, and seizures.

Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs interact differently in each person, we cannot guarantee that this information includes all possible interactions. This information is not a substitute for medical advice. Always speak with your healthcare provider about possible interactions with all prescription drugs, vitamins, herbs and supplements, and over-the-counter drugs that you are taking.

People with liver disease

Don’t use this medication if you have serious liver disease. It may further damage your liver, which could be fatal. Your doctor may take blood tests to make sure your liver is working.

People with heart problems

If you have a history of heart attack or abnormal heart rate, take this drug with caution. It may cause low blood pressure, faster or abnormal heart rate, or heart attack.

People with mental health conditions

If you have a history of mental health conditions, such as depression or substance abuse, take interferon alfa-2b with caution. It may make your condition worse. Your doctor may have you stop taking this drug if you have thoughts of harming yourself or others or other serious mental health problems.

People with thyroid disease

If you have thyroid problems that can’t be controlled with medication, don’t take interferon alfa-2b. It can worsen your condition. Your doctor will need to check your thyroid before and during treatment with interferon alfa-2b.

People with autoimmune disease

Interferon alfa-2b may worsen rheumatoid arthritis, lupus, psoriasis, or similar conditions where your immune system attacks your body. It may also cause you to develop these conditions. Don’t take this drug if you have autoimmune disease.

People with diabetes

If you have diabetes that can’t be controlled with medication, don’t take interferon alfa-2b. It can increase your blood sugar levels and make your diabetes worse.

Pregnant women

Interferon alfa-2b is a category C pregnancy drug. That means two things:

  1. Research in animals has shown adverse effects to the fetus when the mother takes the drug.
  2. There haven’t been enough studies done in humans to be certain how the drug might affect the fetus.

If you take interferon alfa-2b with the medication ribavirin for the treatment of hepatitis, it is a category X drug. Category X drugs should never be used during pregnancy.

Tell your doctor if you’re pregnant or plan to become pregnant. Interferon alfa-2b should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Women who are nursing

Interferon alfa-2b has been shown to pass through breast milk. If it does, it could cause serious effects in a breastfeeding child.

Tell your doctor if you’re breastfeeding. You and your doctor may need to decide if you’ll take interferon alfa-2b or breastfeed.

For Seniors

If you’re over 65 years of age, use Interferon alfa-2b with caution. As you age, your organs, such as your liver and kidneys, don’t work as well as they once did. You are more likely to have other conditions or be taking other drugs, which may interact with this medication.

For Children

The safety and effectiveness of interferon alfa-2b haven’t been established in people younger than 18 years old for conditions other than chronic hepatitis B virus infection and chronic hepatitis C virus infection.

The safety and effectiveness of interferon alfa-2b for the treatment of chronic hepatitis B infection haven’t been established for children younger than 1 year old.

The safety and effectiveness of interferon alfa-2b for the treatment of chronic hepatitis C infection haven’t been established for children younger than 3 years old.

Special Kid Safety

Keep this medication and needles out of reach of children.

Allergies

Interferon alfa-2b can cause a severe allergic reaction. Symptoms may include:

  • trouble breathing
  • swelling of your throat or tongue
  • hives
  • itching
  • feeling faint
  • chest pain
  • anxiousness
  • blistering or peeling of the skin
  • swelling of your face, eyes, and lips

Don’t take this drug again if you’ve ever had an allergic reaction to it. Taking it again could be fatal.

SECTION 4 of 4

How to Take interferon-alfa-2b (Dosage)

Parenteral Solution

All possible dosages and forms may not be included here. Your dose, form, and how often you take it will depend on:

  • your age
  • the condition being treated
  • how severe your condition is
  • other medical conditions you have
  • how you react to the first dose

What Are You Taking This Medication For?

Hairy cell leukemia
Form: Powder for injection, Solution for injection
Strength: 10 million international units (IU) per vial, 18 million IU/vial, 50 million IU/vial, 18 million IU per multidose vial, 25 million IU per multidose vial
Adult Dosage (ages 18 years and older)
  • The recommended dose is 2 million IU per meter squared (m2) of body surface area.
  • The injection is given in your muscle or under your skin 3 times per week for up to 6 months.
  • If you have severe side effects or abnormal test results, your doctor may decrease your dose or decide to stop treatment.
Child Dosage (ages 0–17 years)

Dosage for people younger than 18 years hasn’t been established.

Senior Dosage (ages 65 years and older)

Use interferon alfa-2b with caution. As you age, your organs, such as your heart, kidneys, and liver, may not work as well. This could cause the drug to build up in your body and lead to more side effects. Your doctor may start you at a lower dose.

Special Considerations

Kidney problems: If you have kidney problems, your body will not be able to clear out this drug as well. This may lead to more of the drug staying in your body and will increase your chances for side effects. Your doctor may start you at a lower dose. If your kidney function gets worse, your doctor may stop your medication.

Malignant melanoma
Form: Powder for injection, Solution for injection
Strength: 10 million international units (IU) per vial, 18 million IU/vial, 50 million IU/vial, 18 million IU per multidose vial, 25 million IU per multidose vial
Adult Dosage (ages 18 years and older)

Treatment is given in two phases:

  • The starting dose is 20 million IU per meter squared (m2) of body surface area.
  • It’s given through a needle in your vein over 20 minutes. It’s given 5 consecutive days per week for 4 weeks.
  • The maintenance dose is 10 million IU/m2 given as an injection under your skin.
  • It’s given 3 times per week for 48 weeks. If you have severe side effects or abnormal test results, your doctor may decrease your dose or decide to stop treatment.
Child Dosage (ages 0–17 years)

Dosage for people younger than 18 years hasn’t been established.

Senior Dosage (ages 65 years and older)

Use interferon alfa-2b with caution. As you age, your organs, such as your heart, kidneys, and liver, may not work as well. This could cause the drug to build up in your body and lead to more side effects. Your doctor may start you at a lower dose.

Special Considerations

Kidney problems: If you have kidney problems, your body will not be able to clear out this drug as well. This may lead to more of the drug staying in your body and will increase your chances for side effects. Your doctor may start you at a lower dose. If your kidney function gets worse, your doctor may stop your medication.

Follicular lymphoma
Form: Powder for injection, Solution for injection
Strength: 10 million international units (IU) per vial, 18 million IU/vial, 50 million IU/vial, 18 million IU per multidose vial, 25 million IU per multidose vial
Adult Dosage (ages 18 years and older)
  • The recommended dose is 5 million IU given as an injection under your skin. It’s given 3 times per week for up to 18 months.
  • If you have severe side effects or abnormal test results, your doctor may decrease your dose or decide to stop treatment.
Child Dosage (ages 0–17 years)

Dosage for people younger than 18 years hasn’t been established.

Senior Dosage (ages 65 years and older)

Use interferon alfa-2b with caution. As you age, your organs, such as your heart, kidneys, and liver, may not work as well. This could cause the drug to build up in your body and lead to more side effects. Your doctor may start you at a lower dose.

Special Considerations

Kidney problems: If you have kidney problems, your body will not be able to clear out this drug as well. This may lead to more of the drug staying in your body and will increase your chances for side effects. Your doctor may start you at a lower dose. If your kidney function gets worse, your doctor may stop your medication.

Warts from human papillomavirus
Form: Powder for injection, Solution for injection
Strength: 10 million international units (IU) per vial, 18 million IU/vial, 50 million IU/vial, 18 million IU per multidose vial, 25 million IU per multidose vial
Adult Dosage (ages 18 years and older)
  • The recommended dose is 1 million IU per lesion, with a maximum of 5 lesions in a single course.
  • Lesions should be injected 3 times per week on alternate days for 3 weeks. You may take an additional course given at weeks 12 to 16.
Child Dosage (ages 0–17 years)

Dosage for people younger than 18 years hasn’t been established.

Senior Dosage (ages 65 years and older)

Use interferon alfa-2b with caution. As you age, your organs, such as your heart, kidneys, and liver, may not work as well. This could cause the drug to build up in your body and lead to more side effects. Your doctor may start you at a lower dose.

Special Considerations

Kidney problems: If you have kidney problems, your body will not be able to clear out this drug as well. This may lead to more of the drug staying in your body and will increase your chances for side effects. Your doctor may start you at a lower dose. If your kidney function gets worse, your doctor may stop your medication.

Kaposi's sarcoma
Form: Powder for injection, Solution for injection
Strength: 10 million international units (IU) per vial, 18 million IU/vial, 50 million IU/vial, 18 million IU per multidose vial, 25 million IU per multidose vial
Adult Dosage (ages 18 years and older)
  • The recommended dose is 30 million IU per meter squared (m2) of body surface area.
  • It’s given as an injection under your skin or in your muscle. It’s given 3 times per week up to 16 weeks.
  • If you have severe side effects or abnormal test results, your doctor may decrease your dose or decide to stop treatment.
Child Dosage (ages 0–17 years)

Dosage for people younger than 18 years hasn’t been established.

Senior Dosage (ages 65 years and older)

Use interferon alfa-2b with caution. As you age, your organs, such as your heart, kidneys, and liver, may not work as well. This could cause the drug to build up in your body and lead to more side effects. Your doctor may start you at a lower dose.

Special Considerations

Kidney problems: If you have kidney problems, your body will not be able to clear out this drug as well. This may lead to more of the drug staying in your body and will increase your chances for side effects. Your doctor may start you at a lower dose. If your kidney function gets worse, your doctor may stop your medication.

Chronic hepatitis C infection
Form: Powder for injection, Solution for injection
Strength: 10 million international units (IU) per vial, 18 million IU/vial, 50 million IU/vial, 18 million IU per multidose vial, 25 million IU per multidose vial
Adult Dosage (ages 18 years and older)
  • The recommended dose is 3 million IU given as an injection under your skin or in your muscle. It’s given 3 times per week for 16 weeks.
  • If you tolerate the medication well, treatment can be extended to 18–24 months to improve your response.
  • If you have severe side effects or abnormal test results, your doctor may decrease your dose or decide to stop treatment.
Child Dosage (ages 3–17 years)
  • The dose of interferon alfa-2b is determined using your child’s body surface area (BSA). BSA is the measured or calculated surface area of a human body.  It is measured in squared meters (m2).
  • Interferon alfa-2b must be taken in combination with ribavirin for chronic hepatitis C in children 3 years and older.
  • If your child reaches their eighteenth birthday while taking these medications, they should continue using the child dosing instead of switching to adult dosing.
  • Ribavirin dose: 15 mg/kg/day
  • Interferon alfa-2b dose: 60 mcg/m2/week
  • Treatment duration:
    • Genotype 1: 48 weeks
    • Genotype 2 and 3: 24 weeks
Child Dosage (ages 0–2 years)

Dosage for people younger than 3 years hasn’t been established.

Senior Dosage (ages 65 years and older)

Use interferon alfa-2b with caution. As you age, your organs, such as your heart, kidneys, and liver, may not work as well. This could cause the drug to build up in your body and lead to more side effects. Your doctor may start you at a lower dose.

Special Considerations

Kidney problems: If you have kidney problems, your body will not be able to clear out this drug as well. This may lead to more of the drug staying in your body and will increase your chances for side effects. Your doctor may start you at a lower dose. If your kidney function gets worse, your doctor may stop your medication.

Chronic hepatitis B infection
Form: Powder for injection, Solution for injection
Strength: 10 million international units (IU) per vial, 18 million IU/vial, 50 million IU/vial, 18 million IU per multidose vial, 25 million IU per multidose vial
Adult Dosage (ages 18 years and older)
  • The recommended dose is 30--35 million IU given as an injection under your skin or in your muscle for 16 weeks.
  • It can be given as 5 million IU each day or 10 million IU 3 times a week.
  • If you have severe side effects or abnormal test results, your doctor may decrease your dose or decide to stop treatment.
Child Dosage (ages 1–17 years)
  • The recommended dose is 3 million IU per meter squared (m2) of body surface area.
  • It’s given under your skin three times a week for the first week. Then the dose is increased to 6 million IU/m2 given as an injection under your skin three times a week.
  • The total treatment time is 16–24 weeks.
Child Dosage (ages under 1 year)

Dosage for people younger than 1 year hasn’t been established.

Senior Dosage (ages 65 years and older)

Use interferon alfa-2b with caution. As you age, your organs, such as your heart, kidneys, and liver, may not work as well. This could cause the drug to build up in your body and lead to more side effects. Your doctor may start you at a lower dose.

Special Considerations

Kidney problems: If you have kidney problems, your body will not be able to clear out this drug as well. This may lead to more of the drug staying in your body and will increase your chances for side effects. Your doctor may start you at a lower dose. If your kidney function gets worse, your doctor may stop your medication.

Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs affect each person differently, we cannot guarantee that this list includes all possible dosages. This information is not a substitute for medical advice. Always to speak with your doctor or pharmacist about dosages that are right for you.
Pharmacist's Advice
Healthline Pharmacist Editorial Team

Make sure to take interferon alfa-2b exactly as prescribed by your doctor.

If You Don’t Take It On Schedule or Stop Taking It

Interferon alfa-2b treats serious cancers and other conditions that can be fatal if left untreated. It’s important to take your medication as directed by your doctor, even if you feel better. Doing so will provide the best chance of managing your condition and improving your quality of life.

If You Take Too Much

If you take too much interferon alfa-2b, call your doctor right away. Your doctor may need to perform blood tests to check your health.

What to Do If You Miss a Dose

If you miss a dose of interferon alfa-2b, take the missed dose as soon as possible during the same day or the next day. Then continue your regular dosing schedule.

If several days go by after you miss a dose, ask your doctor for further instructions.

Don’t inject more than one dose or take more than your prescribed dose without talking to your doctor first.

How to Tell the Drug is Working

Your doctor will perform regular blood tests to tell if interferon alfa-2b is working for you.

Interferon alfa-2b may be used for short-term or long-term treatment.

Important Considerations for Taking Interferon alfa-2b

Store this drug in the refrigerator

  • Powder for injection: Keep in temperatures from 36–46°F (2.2–7.8°C). You should use your medication immediately after mixing it, but you may store it for up to 24 hours in the refrigerator. Throw away any unused medicine left in the vial after you withdraw one dose.
  • Solution for injection: Keep in temperatures from 36–46°F (2.2–7.8°C). Do not freeze it. Keep it away from heat. Throw away any unused medication left in the vial after one month.

Note: Keep your drugs away from areas where they could get wet, such as bathrooms. Store this drug away from moisture and damp locations.

Travel

When traveling with your medication:

  • Always carry your medication with you or in your carry-on bag.
  • Don’t worry about airport X-ray machines. They can’t hurt this medication.
  • You may need to show your pharmacy’s preprinted label to identify the medication. Keep the original pharmacy prescription label with you when traveling.
  • This medication needs to be refrigerated. You may need to use an insulated bag with a cold pack to maintain the cold temperature when traveling.
  • Don’t leave it in the car, especially when the temperature is hot or freezing.
  • Needles and syringes need to be used to take this medicine. Check for special rules about traveling with medicine, needles, and syringes.
  • Be sure to take enough medication with you when you travel. It may be difficult to get more if you run out.

Self-Management

Your doctor should show you how to prepare, measure, and give injections to yourself before your first dose of interferon alfa-2b.

  • Before taking this medication, allow the solution to reach room temperature.
  • To make the injection more tolerable, take interferon alfa-2b in the evening.
  • You can take acetaminophen when injecting yourself with this drug to help reduce the chance of unwanted side effects.
  • Never re-use disposable syringes and needles.

You’ll need sterile alcohol wipes, a syringe, and a needle to take this drug. You may also need a needle clipper and a container for safe disposal of needles and syringes.

Clinical Monitoring

Your doctor may monitor you with certain blood tests before and during treatment with interferon alfa-2b to make sure it’s safe for you to take. Tests include:

  • blood cell counts
  • liver function
  • thyroid function
  • electrolytes

Hidden Costs

Besides the medicine, you’ll need sterile alcohol wipes, syringes, and needles. You may also need a needle clipper and container for safe disposal of needles and syringes.

Insurance

Many insurance companies will require a prior authorization before they approve the prescription and pay for interferon alfa-2b.

Are There Any Alternatives?

There are other drugs available to treat your condition. Some may be more suitable for you than others. Talk to your doctor about possible alternatives.


Show Sources

Content developed in collaboration with University of Illinois-Chicago, Drug Information Group

Medically reviewed by Creighton University, Center for Drug Information and Evidence-Based Practice on June 11, 2015

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Disclaimer: Healthline 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.

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