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Interferon beta-1a Intramuscular Injection

in-ter-feer'-on bay'-ta wun aye

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Why is this medication prescribed?   Return to top

Interferon beta-1a is used to decrease the number of episodes of symptoms and slow the development of disability in patients with relapsing-remitting (symptoms come and go) multiple sclerosis (MS, a disease in which the nerves do not function properly and patients may experience weakness, numbness, loss of muscle coordination and problems with vision, speech, and bladder control). Interferon beta-1a has not been shown to help patients with chronic progressive (symptoms are almost always present and worsen over time) MS. Interferon beta-1a is in a class of medications called immunomodulators. It is not known how interferon beta-1a works to treat MS.

How should this medicine be used?   Return to top

Interferon beta-1a intramuscular injection comes as a powder to be mixed into a solution for injection, and also as a prefilled injection syringe. This medication is injected into a muscle, usually once a week, on the same day each week. It is best to inject the medication at around the same time of day on your injection days, usually in the late afternoon or evening. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Use interferon beta-1a exactly as directed. Do not use more or less of it or use it more often than prescribed by your doctor.

Interferon beta-1a controls the symptoms of MS, but does not cure it. Continue to use interferon beta-1a even if you feel well. Do not stop using interferon beta-1a without talking to your doctor.

You will receive your first dose of interferon beta-1a in your doctor's office. After that, you can inject interferon beta-1a yourself or have a friend or relative perform the injections. Ask your doctor or pharmacist to show you or the person who will be injecting the medication how to inject it.

Your doctor or pharmacist will give you the manufacturer's patient information sheet (medication guide) when you begin treatment with interferon beta-1a and each time you refill your prescription. Read the information carefully and ask your doctor or pharmacist if you have any questions. You can also visit the Food and Drug Administration (FDA) website (http://www.fda.gov/cder) to obtain the interferon beta-1a Medication Guide.

Always use a new, unopened vial or prefilled syringe and needle for each injection. Never reuse vials, syringes, or needles. Throw away used syringes and needles in a puncture-resistant container, kept out of reach of children. Talk to your doctor or pharmacist about how to throw away the puncture-resistant container.

You can inject interferon beta-1a in your upper arms or thighs. Use a different spot for each injection. Keep a record of the date and spot of each injection. Do not use the same spot two times in a row. Do not inject into an area where the skin is sore, red, bruised, scarred, infected, irritated, or abnormal in any way.

To prepare interferon beta-1a powder for injection, follow these steps:

To prepare a prefilled syringe of interferon beta-1a intramuscular injection, follow these steps:

To inject an intramuscular dose of interferon beta-1a, follow these steps:

Other uses for this medicine   Return to top

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?   Return to top

Before using interferon beta-1a,

What special dietary instructions should I follow?   Return to top

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?   Return to top

Inject the missed dose as soon as you remember it. Do not inject interferon beta-1a two days in a row. Do not inject a double dose to make up for a missed dose. Return to your regular dosing schedule the following week. Call your doctor if you miss a dose and have questions about what to do.

What side effects can this medication cause?   Return to top

Interferon beta-1a may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

Some side effects can be serious. The following symptoms are uncommon, but if you experience any of them, call your doctor immediately:

Interferon beta-1a may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online [at http://www.fda.gov/MedWatch/index.html] or by phone [1-800-332-1088].

What storage conditions are needed for this medicine?   Return to top

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store interferon beta-1a prefilled syringes and vials in the refrigerator. Do not freeze interferon beta-1a, and do not expose the medication to high temperatures. If a refrigerator is not available, you can store the vials of interferon beta-1a at room temperature, away from heat and light, for up to 30 days. After you mix interferon beta-1a powder with sterile water, store it in the refrigerator and use it within 6 hours. Use prefilled syringes within 12 hours after you take them out of the refrigerator. Throw away mixed vials or syringes after this time has passed. Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.

In case of emergency/overdose   Return to top

In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.

What other information should I know?   Return to top

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your body's response to interferon beta-1a.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names   Return to top

  • Avonex®

Last Revised - 04/01/2006
Last Reviewed - 08/01/2007


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