Interferon Beta-1a (in-ter-FEER-on BAY-ta-1a)

Reduces frequency of flare-ups (relapses) in people who have multiple sclerosis (MS). Also delays some of the physical disabilities caused by MS.

Brand Name(s):

Avonex, Rebif

When This Medicine Should Not Be Used:

How to Use This Medicine:

Injectable

• Your doctor will prescribe your exact dose and tell you how often it should be given. This medicine is given as a shot under your skin or into a muscle.
• This medicine should come with a Medication Guide. Read and follow these instructions carefully. Ask your doctor or pharmacist if you have any questions. Ask your pharmacist for the Medication Guide if you do not have one. Your doctor might ask you to sign some forms to show that you understand this information.
• A nurse or other trained health professional will give you this medicine.
• You may be taught how to give your medicine at home. Make sure you understand all instructions before giving yourself an injection. Do not use more medicine or use it more often than your doctor tells you to.
• Use only the brand of this medicine that your doctor prescribed. Different brands may not work the same way.
• Rebif® works best if you use it on the same time (usually in the late afternoon or evening) on the same three days (such as Monday, Wednesday, and Friday) at least 48 hours apart each week.
• Avonex® comes as a prefilled syringe or a powder. The powder must be mixed with sterile water before it is given. Do not shake the vial after you add the water. Gently swirl the water and medicine together to mix. The mixture should be clear or slightly yellow. Do not use the mixture if you see particles in it. Use the medicine as soon as possible after mixing. If you cannot give your shot right away, you can keep the syringe in the refrigerator for up to 6 hours. After 6 hours, throw the medicine away and mix another dose.
• You will be shown the body areas where this shot can be given. Use a different body area each time you give yourself a shot. Keep track of where you give each shot to make sure you rotate body areas.
• Use a new needle and syringe each time you inject your medicine.
• After you have used one dose of the prefilled syringe, throw away any medicine left in the syringe. Do not reuse needles or syringes.

If a dose is missed:

• If you miss a dose or forget to use your medicine, use it as soon as you can. This will then change the time for your next dose. After using the missed dose, use your next regular dose of Rebif® 48 hours later and go back to your regular schedule the following week. For Avonex®, if your next regular dose is less than 2 days away, call your doctor. For either brand, do not use extra medicine to make up for a missed dose and do not use this medicine two days in a row.

How to Store and Dispose of This Medicine:

• If you store this medicine at home, keep it in the refrigerator. Do not freeze. If refrigeration is not available, Rebif® prefilled syringes and Avonex® powder vials may be kept for up to 30 days at room temperature, away from heat (temperatures above 77 degrees F) and direct light. Avonex® prefilled syringes may be stored for up to 7 days at room temperature, away from heat (temperatures above 77 degrees F) and direct light. You may allow the Avonex® prefilled syringes to warm to room temperature for 30 minutes just before injection, but do not heat in a microwave oven or with hot water.
• Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any leftover medicine, containers, and other supplies. You will also need to throw away old medicine after the expiration date has passed.
• Throw away used needles in a hard, closed container that the needles cannot poke through. Keep this container away from children and pets.
• Keep all medicine away from children and never share your medicine with anyone.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

• Do not drink alcohol while you are using this medicine.

Warnings While Using This Medicine:

• Using this medicine while you are pregnant may cause you to lose your baby or can harm your unborn baby. Tell your doctor right away if you think you are pregnant or if you plan to become pregnant while using this medicine.
• Make sure your doctor knows if you are breastfeeding, or if you have liver disease, bone marrow problems, heart disease (such as cardiomyopathy), congestive heart failure, heart rhythm problems (such as arrhythmia), a history of severe chest pain (angina), thyroid problems, or a history of epilepsy or seizures. Tell your doctor if you have an autoimmune disorder (such as autoimmune hepatitis, idiopathic thrombocytopenia) or a history of depression or other emotional problems.
• This medicine may cause some people to be anxious, irritable, or display other abnormal behaviors. It may also cause some people to have suicidal thoughts and tendencies or to become more depressed. If you or your caregiver notice any of these side effects, tell your doctor right away.
• Check with your doctor right away if you have pain or tenderness in the upper stomach; pale stools; dark urine; loss of appetite; nausea; unusual tiredness or weakness; or yellow eyes or skin. These could be symptoms of a serious liver problem.
• This medicine may cause serious allergic reactions including anaphylaxis. Anaphylaxis can be life-threatening and requires immediate medical attention. Call your doctor right away if you have a rash; itching; hoarseness; trouble breathing; trouble swallowing; or any swelling of your hands, face, or mouth while you are using this medicine.
• This medicine lowers the number of some types of blood cells in your body. Because of this, you may bleed or get infections more easily. To help with these problems, avoid being near people who are sick or have infections. Wash your hands often. Stay away from rough sports or other situations where you could be bruised, cut, or injured. Brush and floss your teeth gently. Be careful when using sharp objects, including razors and fingernail clippers.
• This medicine commonly causes a flu-like reaction, with aching muscles, chills, fever, headache, joint pain, and nausea. Using your shot at bedtime may allow you to sleep through the symptoms. Your doctor may want you to take a medicine for pain and fever (such as acetaminophen or ibuprofen) to help control these side effects. Follow your doctor's instructions carefully about how to prevent or treat these symptoms.
• This medicine is made from donated human blood. Some human blood products have transmitted certain viruses to people who have received them. The risk of getting a virus from medicines made of human blood has been greatly reduced in recent years. This is the result of required testing of human donors for certain viruses, and testing during manufacture of these medicines. Although the risk is low, talk with your doctor if you have concerns. The Avonex® ready to use syringe does not contain albumin which comes from donated human blood.
• This medicine may cause redness, pain, or swelling at the injection site. Some patients have developed skin infections or a permanent depression (necrosis) under the skin at the injection site. Contact your doctor right away if you notice any of these side effects at the injection site: depressed or indented skin; blue-green to black skin discoloration; or pain, redness, or sloughing (peeling) of the skin.
• Do not change your dose without checking first with your doctor.
• Your doctor will need to check your blood at regular visits while you are using this medicine. Be sure to keep all appointments.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

• Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
• Change in how much or how often you urinate, difficult or painful urination.
• Chest pain or fast heartbeat.
• Dark-colored urine or pale stools.
• Depressed mood, thoughts of hurting yourself or others.
• Fever, chills, cough, runny or stuffy nose, sore throat, and body aches.
• Nausea, vomiting, loss of appetite, or pain in your upper stomach.
• Numbness, tingling, or burning pain in your hands, arms, legs, or feet.
• Severe or ongoing pain, redness, or swelling where the shot is given.
• Seizures.
• Shortness of breath, cold sweat, and bluish-colored skin.
• Swelling in your hands, ankles, or feet.
• Swollen, painful, or tender lymph glands in the neck, armpit, or groin.
• Unusual bleeding, bruising, or weakness.
• Yellowing of your skin or the whites of your eyes.
• Weight changes.

If you notice these less serious side effects, talk with your doctor:

• Changes in vision.
• Changes in your menstrual periods.
• Headache or dizziness.
• Mild nausea, diarrhea, or stomach pain.
• Muscle, back, or bone pain.
• Skin rash.

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088