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Generic Name: interferon beta-1b (in ter FEAR on BAY ta 1b)
Brand Name: Betaseron, Extavia

What is interferon beta-1b?

Interferon beta-1b is made from human proteins. Interferons help the body fight viral infections.

Interferon beta-1b is used to treat relapsing multiple sclerosis (MS). This medicine will not cure MS, it will only decrease the frequency of relapse symptoms.

Interferon beta-1b may also be used for purposes not listed in this medication guide.

What is the most important information I should know about interferon beta-1b?

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

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What should I discuss with my healthcare provider before using interferon beta-1b?

You should not use this medicine if you are allergic to interferon beta, albumin, or mannitol.

To make sure interferon beta-1b is safe for you, tell your doctor if you have:

  • liver disease;

  • congestive heart failure;

  • epilepsy or other seizure disorder;

  • a bleeding or blood-clotting disorder, such as hemophilia;

  • a history of low white blood cell (WBC) counts;

  • anemia (lack of red blood cells); or

  • a history of depression or suicidal behavior.

A small number of pregnant women have had miscarriages while using interferon beta-1b. Do not use interferon beta-1b if you are pregnant. Tell your doctor if you become pregnant during treatment.

It is not known whether interferon beta-1b passes into breast milk or if it could harm a nursing baby. You should not breast-feed while using this medicine.

Interferon beta-1b 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 should I use interferon beta-1b?

Follow all directions on your prescription label. Your doctor may occasionally change your dose to make sure you get the best results. Do not use this medicine in larger or smaller amounts or for longer than recommended.

Interferon beta-1b is injected under the skin once every 48 hours (2 days). You may be shown how to use injections at home. Do not self-inject this medicine if you do not understand how to give the injection and properly dispose of used needles and syringes.

Read all patient information, medication guides, and instruction sheets provided to you. Ask your doctor or pharmacist if you have any questions.

Interferon beta-1b is a powder medicine that must be mixed with a liquid (diluent) before using it. If you are using the injections at home, be sure you understand how to properly mix the medicine.

Store unmixed medicine at room temperature away from moisture and heat.

After mixing interferon beta-1b, store in the refrigerator and use within 3 hours. Do not freeze.

Each single-use vial (bottle) of this medicine is for one use only. Throw away after one use, even if there is still some medicine left in it after injecting your dose.

Your care provider will show you the best places on your body to inject interferon beta-1b. Use a different place each time you give an injection. Do not inject into the same place two times in a row.

You will need frequent blood tests to check your liver function.

Use a disposable needle and syringe only once. Follow any state or local laws about throwing away used needles and syringes. Use a puncture-proof "sharps" disposal container (ask your pharmacist where to get one and how to throw it away). Keep this container out of the reach of children and pets.

What happens if I miss a dose?

Use the missed dose as soon as you remember. Then wait at least 48 hours before using another injection, and restart your dosing schedule at that time. Do not use more than one injection every 48 hours (2 days).

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 beta-1b?

Avoid injecting this medicine into skin that is sore, red, or infected.

Drinking alcohol with this medicine can cause serious side effects.

Avoid being near people who are sick or have infections. Tell your doctor at once if you develop signs of infection.

Interferon beta-1b side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Report any new or worsening symptoms to your doctor, such as: mood or behavior changes, anxiety, trouble sleeping, hallucinations, or if you feel impulsive, angry, aggressive, more depressed, or have thoughts about suicide or hurting yourself.

Stop using interferon beta-1b and call your doctor at once if you have:

  • depressed mood, thoughts about hurting yourself;

  • seizure (convulsions);

  • pain, swelling, redness, or skin changes where the injection was given;

  • easy bruising or bleeding;

  • heart problems--fast heartbeats, shortness of breath (especially when lying down), tight feeling in your chest, swelling in your ankles, rapid weight gain;

  • liver problems--nausea, upper stomach pain, itching, tired feeling, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes); or

  • low white blood cell counts--fever, chills, swollen gums, painful mouth sores, pain when swallowing, skin sores, cold or flu symptoms, cough.

Common side effects may include:

  • headache, weakness;

  • sleep problems (insomnia);

  • stomach pain;

  • muscle pain or stiffness;

  • abnormal liver function tests;

  • skin rash;

  • flu symptoms; or

  • skin reaction where the medicine was injected.

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.

See also: Side effects (in more detail)

What other drugs will affect interferon beta-1b?

Other drugs may interact with interferon beta-1b, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Where can I get more information?

  • Your pharmacist can provide more information about interferon beta-1b.
  • 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.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2012 Cerner Multum, Inc. Version: 4.01. Revision Date: 2015-02-03, 3:31:55 PM.