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

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Do not use PegIntron and ribavirin if you are pregnant, or if you are a man and your sexual partner is pregnant. Prevent pregnancy while using this medicine, and for at least 6 months after you stop using it.

PegIntron can cause life-threatening infections, autoimmune disorders, serious mood or behavior problems, or a stroke.

Stop using this medicine and call your doctor at once if you have any unusual changes in mood or behavior, such as: depression, irritability, aggression, or thoughts about suicide or hurting yourself.

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:

  • liver failure; or

  • autoimmune hepatitis.

You should not use PegIntron with ribavirin if you have:

  • severe kidney disease;

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

  • 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:

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

  • a history of depression, mental illness, suicidal thoughts, alcoholism, or drug addiction;

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

  • lung disease;

  • an autoimmune disorder such as rheumatoid arthritis, lupus, or psoriasis;

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

  • HIV or AIDS;

  • diabetes;

  • high triglycerides (a type of fat in the blood);

  • a thyroid disorder;

  • kidney disease (or if you are on dialysis);

  • a weak immune system caused by cancer or other conditions;

  • ulcerative colitis; or

  • a history of organ transplant.

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 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 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.

PegIntron should not be used in a child younger than 3 years old.

How should I use PegIntron?

Follow all directions on your prescription label. Your doctor may occasionally change your dose to make sure you get the best results. Do not use this medicine in larger or smaller amounts or for longer than recommended.

PegIntron is usually given once per week as an injection 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. Also be sure you understand how to properly mix and store the medicine.

Do not shake the injection pen or mixed medicine or you may ruin the medicine. 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 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 (PegIntron) side effects

Get emergency medical help if you have signs of an allergic reaction to PegIntron: hives, or a rash that spreads and causes blistering and peeling; chest pain, anxiety, difficult breathing; swelling of your face, lips, tongue, or throat.

PegIntron can cause life-threatening infections, autoimmune disorders, serious mood or behavior problems, or a stroke.

Stop using PegIntron and call your doctor at once if you have unusual changes in mood or behavior, such as: depression, irritability, aggression, hallucinations, thoughts about hurting yourself, or falling back into a previous pattern of drug addiction. Once you have had this type of reaction to PegIntron, you may not be able to use it again.

Call your doctor at once if you have other serious side effects, such as:

  • vision loss;

  • severe stomach pain with bloody diarrhea;

  • pale skin, easy bruising, unusual bleeding;

  • sudden chest discomfort, wheezing, cough with mucus, feeling short of breath;

  • numbness, tingling, or burning pain in your arms or legs;

  • signs of infection - fever, chills, body aches, cough with yellow or pink mucus, pain or burning when you urinate;

  • pancreas problems - severe pain in your upper stomach spreading to your back, vomiting, fever;

  • high blood sugar - increased thirst or urination, hunger, fruity breath odor, tiredness, weight loss;

  • signs of a stroke or heart attack - chest pain spreading to your jaw or shoulder, sweating, sudden numbness or weakness (especially on one side of the body), sudden severe headache, slurred speech, problems with balance;

  • new or worsened autoimmune disorders - skin problems, joint pain or swelling, cold feeling or pale appearance in your fingers or toes;

  • thyroid problems - weight changes, skin changes, thinking problems, feeling hot or cold all the time; or

  • worsening liver symptoms - upper stomach pain or swelling, loss of appetite, jaundice (yellowing of the skin or eyes).

Common PegIntron side effects may include:

  • flu-like symptoms, weakness, feeling tired;

  • mild depression or sadness, feeling anxious or irritable;

  • nausea, vomiting, loss of appetite, weight loss;

  • thinning hair; or

  • redness, swelling, or itching 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?

Tell your doctor about all your current medicines and any you start or stop using, especially:

  • telbivudine.

This list is not complete. Other drugs may interact with peginterferon alfa-2b, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Where can I get more information?

  • Your doctor or 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: 17.04. Revision Date: 2015-10-08, 7:03:37 AM.