Interferon Beta-1a Subcutaneous Injection

pronounced as (in ter feer' on)

Brand Name(s): Rebif®

Why is this medicine prescribed?

Interferon beta-1a subcutaneous injection is used to treat adults with various forms of multiple sclerosis (MS; a disease in which the nerves do not function properly and people may experience weakness, numbness, loss of muscle coordination, and problems with vision, speech, and bladder control) including:

  • clinically isolated syndrome (CIS; nerve symptom episodes that last at least 24 hours),
  • relapsing-remitting forms (course of disease where symptoms flare up from time to time), or
  • secondary progressive forms (course of disease where relapses occur more often).

Interferon beta-1a is in a class of medications called immunomodulators. It works by decreasing inflammation and preventing nerve damage that may cause symptoms of multiple sclerosis.

Are there other uses for this medicine?

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

How should this medicine be used?

Interferon beta-1a subcutaneous injection comes as a solution (liquid) in a prefilled syringe or a prefilled automatic injection device to inject subcutaneously (under the skin). It is usually injected three times a week. You should inject this medication on the same 3 days every week, for example, every Monday, Wednesday, and Friday. The injections should be spaced at least 48 hours apart, so it is best to inject your medication around the same time of day on each of your injection days. The best time to inject this medication is 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.

Your doctor may start you on a low dose of interferon beta-1a and gradually increase your dose, not more than once every 2 weeks.

Interferon beta-1a controls 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 subcutaneous in your doctor's office. After that, you can inject interferon beta-1a subcutaneous 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. Before you use interferon beta-1a subcutaneous for the first time, your or the person who will be giving the injections should also read the manufacturer's information for the patient that comes with it. Follow the directions carefully.

Use a new prefilled syringe or prefilled automatic injection device each time you inject your medication. Do not reuse or share syringes or automatic injection devices. Even if there is still some solution left in the syringe or device after you inject, do not inject again. Discard used syringes or automatic injection devices in a puncture resistant container that is out of the reach of children. Talk to your doctor or pharmacist about how to discard the puncture-resistant container.

Always look at the medication in your prefilled syringe or automatic injection device before you use it. It should be a clear to slightly yellow solution. If the solution is cloudy, discolored, or contains particles or if the expiration date marked on the syringe or automatic injection device has passed, do not use that syringe or device.

Talk to your doctor or pharmacist about where on your body you should inject interferon beta-1a subcutaneous. You can inject interferon beta-1a in areas of your body with a layer of fat between the skin and muscle, such as your thigh, the outer surface of your upper arms, your stomach, or your buttocks. If you are very thin, only inject in your thigh or the outer surface of your arm for injection. Choose a different spot each time you inject your medication. 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 near your navel (belly button) or waistline or into an area where the skin is sore, red, bruised, scarred, infected, or abnormal in any way.

Your doctor or pharmacist will give you the manufacturer's patient information sheet (Medication Guide) when you begin treatment with interferon beta-1a subcutaneous injection 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 ( ) or the manufacturer's website to obtain the Medication Guide.

What special precautions should I follow?

Before using interferon beta-1a,

  • tell your doctor and pharmacist if you are allergic to interferon beta-1a, any other interferon medications (Avonex, Betaseron, Extavia, Plegridy), any other medications, or human albumin. Ask your pharmacist or check the Medication Guide for a list of the ingredients.
  • tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if you drink or have ever drunk large amounts of alcohol; if you have or have ever had an autoimmune disease (a disease in which the body attacks its own cells; ask your doctor if you are not sure if you have this type of disease); anemia (low red blood cells) or low white blood cells; blood problems such as easy bruising or bleeding or blood clots; mental illness such as depression, especially if you have ever thought about killing yourself or tried to do so; seizures; pulmonary arterial hypertension (PAH; high blood pressure in the vessels carrying blood to the lungs, causing shortness of breath, dizziness, and tiredness); heart failure; or heart, kidney, liver, or thyroid disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while using interferon beta-1a subcutaneous, call your doctor immediately.
  • you should know that you may have flu-like symptoms such as headache, fever, chills, sweating, muscle aches, back pain, and tiredness after your injection. Your doctor may tell you to take an over-the-counter pain and fever medication to help with these symptoms. These symptoms usually improve or go away over time. Talk to your doctor if these symptoms are difficult to manage or become severe.
  • if you are having surgery, including dental surgery, tell the doctor or dentist you are using interferon beta-1a subcutaneous.
  • ask your doctor about the safe use of alcoholic beverages while you are using interferon beta-1a subcutaneous. Alcohol can make the side effects of interferon beta-1a worse.

What special dietary instructions should I follow?

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

What should I do if I forget to take a dose?

Inject the missed dose as soon as you remember it. If you are scheduled for a dose the following day, skip that dose. Do not inject interferon beta-1a subcutaneous 2 days in a row. Do not inject a double dose to make up for a missed dose. You should 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 should I do in case of overdose?

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at . If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What side effects can this medicine cause?

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

  • headache
  • chills
  • dry eyes
  • vision problems
  • dry mouth
  • bruising, pain, redness, swelling, or tenderness at the injection site

Some side effects can be serious. If you experience any of these symptoms call your doctor immediately or get emergency medical treatment:

  • new or worsening depression
  • thinking about harming or killing yourself or planning or trying to do so
  • anxiety
  • hives
  • rash
  • itching
  • mouth sores
  • blistering or peeling skin
  • difficulty breathing or swallowing
  • swelling of the eyes, face, mouth, tongue, or throat
  • lightheadedness
  • fainting
  • seizures
  • loss of coordination
  • extreme tiredness
  • lack of energy
  • nausea
  • vomiting
  • loss of appetite
  • pale stools
  • pain in the upper right part of the stomach
  • yellowing of the skin or eyes
  • dark urine
  • pale skin
  • confusion
  • chest pain
  • fast heartbeat
  • unusual bruising or bleeding
  • sore throat, cough, fever, chills, or other signs of infection
  • swelling of the feet, ankles, or lower legs
  • unexplained weight gain or loss
  • feeling cold or hot all the time
  • blue or black discoloration of skin, swelling, or drainage at the injection site
  • red or bloody stools or diarrhea
  • stomach pain
  • slow or difficult speech
  • purple patches or pinpoint dots (rash) on the skin
  • decreased urination or blood in the urine
  • new or increasing fatigue or shortness of breath

Interferon beta-1a may cause other side effects. Call your doctor if you have any unusual problems while using 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 ( ) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it in the refrigerator, but do not freeze it. If a refrigerator is not available, you can store the medication at room temperature away from heat and light for up to 30 days.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach.

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website ( ) for more information if you do not have access to a take-back program.

What other information should I know?

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 subcutaneous injection.

Do not let anyone else use 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.

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