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Generic Name: peginterferon alfa-2b (peg in ter FEAR on AL fa 2 b)
Brand Names: PegIntron, PegIntron Redipen, Sylatron

What is PegIntron?

PegIntron (peginterferon alfa-2b) is made from human proteins that help the body fight viral infections.

PegIntron is used to treat chronic hepatitis C in adults. PegIntron is often used in combination with another medication called ribavirin (Rebetol, Ribasphere) to treat hepatitis C in adults and children who are at least 3 years old.

PegIntron may be used in combination with boceprevir (Victrelis) or telaprevir (Incivek) to treat hepatitis C in adults. The Sylatron brand of peginterferon alfa-2b is used to treat melanoma (skin cancer) after surgery.

Important information

You should not use PegIntron if you have autoimmune hepatitis, liver failure, severe kidney disease, or a hemoglobin blood cell disorder such as sickle-cell anemia or thalassemia.

Do not use PegIntron together with ribavirin if you are pregnant, or if you are a man and your female sexual partner is pregnant.

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Stop using PegIntron and call your doctor at once if you have severe or worsening symptoms such as: confusion, depression, tired feeling, anxiety, aggression, tremors, muscle twitching, seizure, unusual thoughts or behavior, or thoughts about suicide or hurting yourself. Once you have had this type of reaction to PegIntron, you must never use it again.

Before taking this medicine

You should not use PegIntron if you are allergic to peginterferon alfa-2b or other alfa interferons (Intron A, Rebetron, Alferon N, Infergen, Pegasys), or if you have:

  • autoimmune hepatitis;

  • liver failure;

  • severe kidney disease;

  • a hemoglobin blood cell disorder such as sickle-cell anemia or thalassemia;

  • if you are pregnant, or if you are a man and your sexual partner is pregnant.

To make sure PegIntron is safe for you, tell your doctor if you have:

  • lung disease;

  • hepatitis B, or liver problems other than hepatitis C;

  • a thyroid disorder;

  • uncontrolled diabetes;

  • new or worsening problems with your eyes;

  • cancer;

  • HIV or AIDS;

  • pancreatitis or ulcerative colitis;

  • heart disease, high blood pressure, high cholesterol or triglycerides, or a history of heart attack, or stroke;

  • dental problems or gum disease;

  • an allergy causing severe reaction;

  • history of organ transplant;

  • anemia (low red blood cells) caused by taking ribavirin (Rebetol);

  • any blood cell disorder causing bleeding episodes, infections, or fever-related illness;

  • an autoimmune disorder such as rheumatoid arthritis, systemic lupus erythematosus (SLE), or psoriasis; or

  • a history of drug or alcohol addiction, depression, anxiety, or suicidal thoughts or behaviors.

PegIntron may be harmful to an unborn baby. Do not use PegIntron without telling your doctor if you are pregnant.

PegIntron is often used together with another medication called ribavirin. Ribavirin is known to cause birth defects or death in an unborn baby. You may need to have a negative pregnancy test before taking these two medications together and every month during your treatment.

  • If you are a woman, do not use PegIntron and ribavirin if you are pregnant.

  • If you are a man, do not use PegIntron and ribavirin if your female sexual partner is pregnant. An unborn baby could also be harmed if a man fathers the child while he is taking ribavirin.

  • Use at least 2 effective forms of birth control while either sexual partner is using PegIntron with ribavirin. Keep using 2 forms of birth control for at least 6 months after treatment ends.

  • Tell your doctor right away if a pregnancy occurs while either the mother or the father is using PegIntron together with ribavirin.

It is not known whether peginterferon alfa-2b passes into breast milk or if it could harm a nursing baby. You should not breast-feed while you are using this medicine.

PegIntron can affect growth in children. Talk with your doctor if you think your child is not growing at a normal rate while using this medication.

How should I use PegIntron?

PegIntron is injected under the skin. You may be shown how to use injections at home. Do not self inject this medicine if you do not fully understand how to give the injection and properly dispose of used needles and syringes.

PegIntron is usually given once per week. Your doctor may occasionally change your dose to make sure you get the best results from this medication. If you are being treated with combination therapy, you will also take ribavirin (Rebetol) capsules or liquid by mouth every day. Ribavirin should be taken with food.

PegIntron is a powder medicine that must be mixed with a liquid (diluent) before using it. If you are using the injections at home, be sure you understand how to properly mix and store the medicine.

Do not shake the PegIntron injection pen or vial (bottle) or you may ruin the medicine. Prepare your dose only when you are ready to give an injection. Do not use if the medicine has changed colors or has particles in it. Call your pharmacist for new medicine.

Use a disposable needle and syringe only once. Follow any state or local laws about throwing away used needles and syringes. Use a puncture-proof "sharps" disposal container (ask your pharmacist where to get one and how to throw it away). Keep this container out of the reach of children and pets.

While using this medicine, you may need frequent medical tests and eye exams.

Store the PegIntron Redipen in a refrigerator. Do not freeze. Mixed medicine may also be stored in the refrigerator but you must use it within 24 hours after mixing. Do not freeze or save any unused mixture.

Store PegIntron or Sylatron vials (bottles) at room temperature away from moisture and heat. Do not freeze. Do not reuse a vial or injection pen.

What happens if I miss a dose?

Use the medicine as soon as you remember the missed dose, then go back to your regular schedule on the day your next dose is due. If you are more than 2 days late in using your injection, call your doctor for instructions. Do not use extra medicine to make up a missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while using PegIntron?

Using this medicine will not prevent you from passing hepatitis to other people. Follow your doctor's instructions about how to prevent passing the disease to another person.

Avoid coffee, tea, cola, energy drinks, or other products that contain caffeine.

PegIntron side effects

Get emergency medical help if you have any of these signs of an allergic reaction to PegIntron: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Stop using PegIntron and call your doctor at once if you have severe or worsening symptoms such as: confusion, depression, tired feeling, anxiety, aggression, tremors, muscle twitching, seizure, unusual thoughts or behavior, or thoughts about suicide or hurting yourself. Once you have had this type of reaction to peginterferon alfa-2b, you must never use it again.

Stop using PegIntron and call your doctor at once if you have:

  • vision problems;

  • fast heart rate, feeling like you might pass out;

  • fever, chills, body aches, flu symptoms, pale skin, easy bruising or bleeding, unusual weakness, pain or burning when you urinate;

  • high fever with severe stomach pain and bloody diarrhea;

  • severe pain in your upper stomach spreading to your back, nausea and vomiting, fast heart rate;

  • cough with mucus, feeling short of breath, chest pain, uneven heartbeats;

  • sudden numbness or weakness, problems with speech or balance; or

  • new or worsening liver symptoms (upper stomach pain, dark urine, jaundice).

Common PegIntron side effects may include:

  • fever, chills, tired feeling, headache, muscle pain;

  • nausea, loss of appetite;

  • abnormal liver function tests; or

  • pain, redness, swelling, or irritation where the medicine was injected.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect PegIntron?

Many drugs can interact with peginterferon alfa-2b. Not all possible interactions are listed here. Tell your doctor about all medicines you use, and any you start or stop using during treatment with PegIntron, especially:

  • fosphenytoin, methadone, phenytoin, rifampin, telbivudine, voriconazole;

  • a blood thinner such as warfarin, Coumadin, Jantoven;

  • ADHD medication such as Adderall, Ritalin, and others;

  • an antidepressant or anti-psychotic medication;

  • cancer medication;

  • cough medicine (prescription or over-the-counter);

  • diabetes medications you take by mouth;

  • heart or blood pressure medication;

  • HIV or AIDS medication;

  • medicines used to prevent organ transplant rejection; or

  • a sulfa drug.

This list is not complete and many other drugs can interact with peginterferon alfa-2b. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Give a list of all your medicines to any healthcare provider who treats you.

Where can I get more information?

  • Your pharmacist can provide more information about PegIntron.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use PegIntron only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2015 Cerner Multum, Inc. Version: 17.03. Revision Date: 2014-12-17, 3:59:05 PM.