What is this medication?

INTERFERON BETA-1a (IN ter FEER on BAY ta 1a) helps to decrease the number of multiple sclerosis attacks and to slow physical disability in people with relapsing forms of the disease. It is not a cure for multiple sclerosis.

This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

COMMON BRAND NAME(S): Avonex, Rebif, Rebif Rebidose

What should I tell my care team before I take this medication?

They need to know if you have any of these conditions:

How should I use this medication?

Rebif is injected under the skin. Avonex is injected into a muscle. You will be taught how to prepare and give it. Take it as directed on the prescription label. Keep taking it unless your health care provider tells you to stop.

It is important that you put your used needles and syringes in a special sharps container. Do not put them in a trash can. If you do not have a sharps container, call your pharmacist or care team to get one.

This medication comes with INSTRUCTIONS FOR USE. Ask your pharmacist for directions on how to use this medication. Read the information carefully. Talk to your pharmacist or care team if you have questions.

A special MedGuide will be given to you by the pharmacist with each prescription and refill. Be sure to read this information carefully each time.

Talk to your care team about the use of this medication in children. Special care may be needed.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses. Each dose should be separated by about 48 hours. If you accidentally take a dose on 2 consecutive days, call your care team.

What may interact with this medication?

Interactions have not been studied.

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medication?

Visit your care team for regular checks on your progress. Tell your care team if your symptoms do not start to get better or if they get worse.

You may need blood work while you are taking this medication.

This medication can cause serious side effects. To reduce the risk, your health care provider may give you other medications to take before receiving this one. Be sure to follow the directions from your health care provider.

This medication can cause a blood clotting problem called thrombotic thrombocytopenic purpura (TTP). TTP is a rare but serious medical condition that can be deadly. Get medical help right away if you have purple spots on your skin or in your mouth; yellowing of the eyes or skin; general ill-feeling or flu-like symptoms; stomach pain; unusually weak or tired; fever; chest pain; trouble breathing; pain swelling or warmth in leg; confusion; severe headaches; trouble speaking; trouble walking; changes in vision; or trouble passing urine.

What side effects may I notice from receiving this medication?

Side effects that you should report to your health care provider as soon as possible:

Side effects that usually do not require medical attention (report to your health care provider if they continue or are bothersome):

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Where should I keep my medication?

Keep out of the reach of children and pets.

Rebif: Store in a refrigerator between 2 and 8 degrees C (36 and 46 degrees F). Do not freeze. If a refrigerator is not available, the medication can be kept cool at or below 25 degrees C (77 degrees F) for up to 30 days. Protect from light. Get rid of any unused medication after the expiration date.

Avonex Pre-filled syringes: Store in a refrigerator between 2 and 8 degrees C (36 and 46 degrees F). Do not freeze. If a refrigerator is not available, the pre-filled syringe can be stored at a temperature at or below 25 degrees C (77 degrees F) for up to 7 days. Protect from light. Get rid of any unused medication after the expiration date.

Avonex Auto-Injector Pens: Store in a refrigerator between 2 and 8 degrees C (36 and 46 degrees F). Do not freeze. If a refrigerator is not available, the auto-injector pen may be stored at a temperature at or below 25 degrees C (77 degrees F) for up to 7 days. Protect from light. Get rid of any unused medication after the expiration date.

To get rid of medications that are no longer needed or have expired:

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

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