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Interferon alfa-2b

Generic name: interferon alfa-2b [ IN-ter-FEAR-on-AL-fa-2b ]
Brand names: Intron A, Intron A
Dosage form: injectable powder for injection (10000000 intl units; 18000000 intl units)
Drug class: Antineoplastic interferons

Medically reviewed by Drugs.com on Aug 14, 2023. Written by Cerner Multum.

What is interferon alfa-2b?

Interferon alfa-2b is used to treat hairy cell leukemia, malignant melanoma, follicular lymphoma, Kaposi's sarcoma caused by AIDS, and certain types of genital warts. Interferon alfa-2b is also used to treat chronic hepatitis B or C in adults, and to treat chronic hepatitis B in children who are at least 1 year old.

Interferon alfa-2b may also be used for purposes not listed in this medication guide.

Interferon alfa-2b side effects

Get emergency medical help if you have signs of an allergic reaction: hives, skin rash with blistering and peeling; anxiety, chest pain, difficult breathing; swelling of your face, lips, tongue, or throat.

Interferon alfa-2b may cause serious side effects. Call your doctor at once if you have:

Your cancer treatments may be delayed or permanently discontinued if you have certain side effects.

Interferon alfa-2b with ribavirin can affect growth in children. Talk with your doctor if you think your child is not growing at a normal rate while using interferon alfa-2b.

Common side effects of interferon alfa-2b may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Warnings

You should not use interferon alfa-2b if you have autoimmune hepatitis, or severe liver problems from causes other than hepatitis B or C.

You should not use interferon alfa-2b with ribavirin if you are pregnant, or if you are a man whose sex partner is pregnant. Use effective birth control to prevent pregnancy while taking ribavirin and for at least 6 months after your last dose.

Interferon alfa-2b can cause life-threatening infections, autoimmune disorders, serious mood or behavior problems, or a stroke.

Call your doctor at once if you have: unusual changes in mood or behavior, chest pain, trouble breathing, sudden numbness or weakness, or signs of infection (fever, chills, cough with mucus, or burning when you urinate).

Before taking this medicine

You should not use interferon alfa-2b if you are allergic to it, or if you have:

You should not use the combination of interferon alfa-2b and ribavirin if you have:

Tell your doctor if you have ever had

Interferon alfa-2b can harm an unborn baby or cause a miscarriage. Interferon alfa-2b is sometimes used in combination with ribavirin. Both men and women using ribavirin should use effective birth control to prevent pregnancy. Ribavirin can cause birth defects, miscarriage, or death to an unborn baby if the mother or father is using interferon alfa-2b.

You should not take ribavirin if you are pregnant, or if you are a man and your sex partner is pregnant. Use effective birth control to prevent pregnancy. Keep using birth control for at least 6 months after your last dose of ribavirin.

Tell your doctor right away if a pregnancy occurs while either the mother or the father is using ribavirin.

You should not breastfeed while using this medicine.

The powder form of interferon alfa-2b is made from human plasma (part of the blood) which may contain viruses and other infectious agents. Donated plasma is tested and treated to reduce the risk of it containing infectious agents, but there is still a small possibility it could transmit disease. Talk with your doctor about the risks and benefits of using this medication.

How is interferon alfa-2b given?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Interferon alfa-2b is injected into a muscle, under the skin, as an infusion into a vein, or directly into a genital wart. A healthcare provider will give your first dose and may teach you how to properly use the medication by yourself.

Your dose needs may change if you switch to a different brand, strength, or form of this medicine. Avoid medication errors by using only the form and strength your doctor prescribes.

Read and carefully follow any Instructions for Use provided with your medicine. Ask your doctor or pharmacist if you don't understand all instructions.

Interferon alfa-2b powder must be mixed with a liquid (diluent) before using it. When using injections by yourself, be sure you understand how to properly mix and store the medicine.

Prepare your injection only when you are ready to give it. Do not use if the medicine looks cloudy, has changed colors, or has particles in it. Call your pharmacist for new medicine.

Interferon alfa-2b can increase your risk of bleeding or infection. You will need frequent medical tests. Your heart, lung, and liver function may also need to be checked.

Interferon alfa-2b can increase your risk of bleeding or infection. You will need frequent medical tests.

Store this medicine in the refrigerator. Do not freeze. After mixing the powder with a diluent, store this mixture in the refrigerator and use it within 24 hours.

Each mixture or single-use vial (bottle) of this medicine is for one use only. Throw it away after one use, even if there is still medicine left inside. Throw away any leftover medicine in a multi-dose vial 30 days after the first use.

Use a needle and syringe only once and then place them in a puncture-proof "sharps" container. Follow state or local laws about how to dispose of this container. Keep it out of the reach of children and pets.

What happens if I miss a dose?

Use the medicine as soon as you remember, and then go back to your regular injection schedule. Do not use two doses at one time.

If several days pass after you miss a dose, call your doctor for instructions.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while using interferon alfa-2b?

Using interferon alfa-2b will not prevent your disease from spreading. Follow your doctor's instructions about how to prevent passing the disease to another person.

Avoid drinking alcohol. It may increase your risk of liver damage.

Avoid driving or hazardous activity until you know how this medicine will affect you. Your reactions could be impaired.

What other drugs will affect interferon alfa-2b?

Tell your doctor about all your other medicines, especially:

This list is not complete. Other drugs may affect interferon alfa-2b, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.