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Relapsing MS treatment not working? Here’s an option.

Peginterferon beta-1a

Generic Name: peginterferon beta-1a (peg-IN-ter-FEER-on BAY-ta)
Brand Name: Plegridy

Peginterferon beta-1a is used for:

Treating relapsing forms of multiple sclerosis (MS).

Peginterferon beta-1a is a protein identical to one found in the body. Exactly how it works is not known. It is thought to interfere with certain substances in the body that cause flare-ups of MS.

Do NOT use peginterferon beta-1a if:

  • you are allergic to any ingredient in peginterferon beta-1a, to interferon beta medicines, or to another peginterferon medicine

Contact your doctor or health care provider right away if any of these apply to you.

Before using peginterferon beta-1a:

Some medical conditions may interact with peginterferon beta-1a. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

  • if you are pregnant, planning to become pregnant, or are breast-feeding
  • if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
  • if you have allergies to medicines, foods, or other substances
  • if you have kidney problems
  • if you have a history of liver problems or abnormal liver function tests, an autoimmune disease (eg, psoriasis, lupus, rheumatoid arthritis), bleeding problems, thyroid problems, low blood cell counts (eg, red or white blood cells, platelets), heart problems (eg, heart failure), seizures, mental or mood problems (eg, depression), or suicidal thoughts or actions
  • if you drink alcohol

Some MEDICINES MAY INTERACT with peginterferon beta-1a. Tell your health care provider if you are taking any other medicines, especially any of the following:

  • Medicines that may harm the liver (eg, acetaminophen, methotrexate, ketoconazole, isoniazid, certain medicines for HIV infection) because the risk of liver side effects may be increased. Ask your doctor if you are unsure if any of your medicines might harm the liver

This may not be a complete list of all interactions that may occur. Ask your health care provider if peginterferon beta-1a may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use peginterferon beta-1a:

Use peginterferon beta-1a as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • Peginterferon beta-1a comes with an extra patient information sheet called a Medication Guide. Read it carefully. Read it again each time you get peginterferon beta-1a refilled.
  • Peginterferon beta-1a also comes with an additional patient leaflet with detailed instructions for use. Talk to your pharmacist if you have questions about this information.
  • Peginterferon beta-1a is usually given as an injection at your doctor's office, hospital, or clinic. If you will be using peginterferon beta-1a at home, a health care provider will teach you how to use it. Be sure you understand how to use peginterferon beta-1a. Follow the procedures you are taught when you use a dose. Contact your health care provider if you have any questions.
  • Do not use peginterferon beta-1a if it contains particles, is cloudy or discolored, or if the pen or syringe is cracked or damaged.
  • Remove peginterferon beta-1a from the refrigerator and allow it to warm to room temperature (about 30 minutes) before you use a dose. Do not use external heat sources (eg, hot water) to warm peginterferon beta-1a.
  • Peginterferon beta-1a is for injection deep under the skin of your stomach, back of the upper arm, or thigh. Use the proper technique taught to you by your doctor. Do NOT inject into muscle or a vein.
  • Do not inject peginterferon beta-1a into an area where the skin is irritated, reddened, bruised, infected, or scarred.
  • Be sure to rotate your injection site with each injection to avoid an injection site reaction.
  • Each prefilled pen and syringe is for one use only. Throw it away after use.
  • Keep this product, as well as syringes and needles, out of the reach of children and pets. Do not reuse needles, syringes, or other materials. Ask your health care provider how to dispose of these materials after use. Follow all local rules for disposal.
  • If you miss a dose of peginterferon beta-1a, use it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not use 2 doses at once. If you are not sure what to do if you miss a dose of peginterferon beta-1a, call your doctor.

Ask your health care provider any questions you may have about how to use peginterferon beta-1a.

Important safety information:

  • Do not change your dose of peginterferon beta-1a or use more often than prescribed without checking with your doctor.
  • Mental or mood problems (eg, depression) and suicidal thoughts or behaviors have been reported in patients taking a medicine like this one. Contact your doctor right away if you experience new or worsening mental or mood problems (eg, aggression, anxiety, depression, hallucinations, irritability, nervousness) or suicidal thoughts or behaviors.
  • Severe liver problems, including cases of liver failure and death, have been reported rarely in patients taking peginterferon beta-1a. Your risk of liver problems may be greater if you drink alcohol while you are using peginterferon beta-1a. Talk to your doctor before drinking alcohol while you are using peginterferon beta-1a.
  • Peginterferon beta-1a commonly causes flu-like symptoms. Talk to your doctor about whether you should take a nonprescription medicine for pain or fever reduction before or after taking peginterferon beta-1a.
  • Peginterferon beta-1a may lower the ability of your body to fight infection. Avoid contact with people who have colds or infections. Tell your doctor if you notice signs of infection like fever, sore throat, rash, or chills.
  • Peginterferon beta-1a may reduce the number of clot-forming cells (platelets) in your blood. Avoid activities that may cause bruising or injury. Tell your doctor if you have unusual bruising or bleeding. Tell your doctor if you have dark, tarry, or bloody stools.
  • Injection-site reactions happen often with peginterferon beta-1a. Sometimes, very bad injection-site reactions may happen. Check your injection site 2 hours after you use peginterferon beta-1a. Check with your doctor if you have any injection-site reactions that do not go away in a few days or become bothersome. Call your doctor right away if you have any break in the skin, color changes (blue or black), swelling, or drainage of fluid at the injection site.
  • Lab tests, including complete blood cell counts, liver function tests, and thyroid function tests, may be performed while you use peginterferon beta-1a. These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.
  • PREGNANCY and BREAST-FEEDING: If you think you may be pregnant, contact your doctor. You will need to discuss the benefits and risks of using peginterferon beta-1a while you are pregnant. It is not known if this medicine is found in breast milk. If you are or will be breast-feeding while you use peginterferon beta-1a, check with your doctor. Discuss any possible risks to your baby.

Possible side effects of peginterferon beta-1a:

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Flu-like symptoms (eg, headache, tiredness, mild fever or chills, muscle aches, weakness); joint pain; nausea; pain or redness at the injection site; vomiting.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, throat, or tongue; feeling faint; anxiety); chest pain; fainting; fast or irregular heartbeat; seizures; severe or persistent dizziness or light-headedness; severe or persistent pain, redness, swelling, or tenderness at the injection site; shortness of breath; sudden unexplained weight gain; swelling of the hands, ankles, legs, or feet; symptoms of infection (eg, fever; chills; persistent sore throat; painful, burning, or increased urination; bloody diarrhea; coughing up mucus); symptoms of liver problems (eg, confusion; dark urine; loss of appetite; pale stools; severe stomach pain; unusual nausea, drowsiness, or tiredness; yellowing of the eyes or skin); symptoms of thyroid problems (eg, trouble concentrating, feeling cold or hot all the time, weight changes, skin changes); unusual bruising or bleeding; unusual tiredness or weakness.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.

If OVERDOSE is suspected:

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately.

Proper storage of peginterferon beta-1a:

Store peginterferon beta-1a in the original carton in the refrigerator, between 36 and 46 degrees F (2 and 8 degrees C). Do not freeze. Do not use peginterferon beta-1a if it has been frozen. If refrigeration is not available, peginterferon beta-1a can be stored at or below 77 degrees F (25 degrees C) for up to 30 days. If peginterferon beta-1a is taken out of the refrigerator, it can be put back in the refrigerator if needed. The total number of days it can be out of the refrigerator must not be more than 30 days. Protect from light. If peginterferon beta-1a has been stored improperly, discard the product and do not use it. Keep peginterferon beta-1a, as well as needles and syringes, out of the reach of children and away from pets.

General information:

  • If you have any questions about peginterferon beta-1a, please talk with your doctor, pharmacist, or other health care provider.
  • Peginterferon beta-1a is to be used only by the patient for whom it is prescribed. Do not share it with other people.
  • If your symptoms do not improve or if they become worse, check with your doctor.
  • Check with your pharmacist about how to dispose of unused medicine.

This information should not be used to decide whether or not to take peginterferon beta-1a or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about peginterferon beta-1a. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to peginterferon beta-1a. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using peginterferon beta-1a.

Review Date: November 3, 2016

Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using this medicine.

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