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Peginterferon Alfa-2b (Injection)

Peginterferon Alfa-2b (peg-in-ter-FEER-on AL-fa-2b)

Treats hepatitis C. May be used alone or together with other medicines.

Brand Name(s):

PEGIntron, Peg Intron RP, Sylatron

There may be other brand names for this medicine.

When This Medicine Should Not Be Used:

You should not use this medicine if you have had an allergic reaction to peginterferon alfa-2b. You should not use this medicine if you have certain liver problems that are getting worse (such as autoimmune hepatitis or cirrhosis). Do not use this medicine together with ribavirin if you are pregnant, if your partner is pregnant, if you have a blood disorder (such as sickle-cell anemia or thalassemia major), or if you have severe kidney disease.

How to Use This Medicine:


  • 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.
  • This medicine should come with a Medication Guide. Ask your pharmacist for a copy if you do not have one.
  • A nurse or other health provider will give you this medicine.It may also be given by a home health caregiver.
  • 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 this medicine on the same day each week and at about the same time of the day.
  • If you switch from using the vial (glass container) to using the prefilled syringe, make sure that you are giving yourself the correct amount of medicine.
  • You might not use all of the medicine in each vial or prefilled syringe. Use each vial or syringe only 1 time. Do not save an open vial or syringe. Do not use the medicine if it has changed color or has particles in it.
  • 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.

If a dose is missed:

  • Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.

How to Store and Dispose of This Medicine:

  • If you store this medicine at home, keep it at room temperature, away from heat, moisture, and direct light.After the powder medicine has been mixed with the liquid, the mixture must be used right away or kept in the refrigerator and used within 24 hours. Do not freeze the powder or the mixture.
  • 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 out of the reach of children. 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.

  • Make sure your doctor knows if you also use flecainide (Tambocor®), methadone (Dolophine®), phenytoin (Dilantin®), medicine to treat hepatitis B, HIV, or AIDS (such as didanosine, lamivudine, stavudine, telbivudine, zidovudine, Combivir®, Retrovir®, Tyzeka®, Videx®, or Zerit®), or a blood thinner (such as warfarin, Coumadin®).

Warnings While Using This Medicine:

  • You can harm your unborn baby if you use this medicine together with ribavirin while you are pregnant. These medicines may also cause birth defects if the father is using it when his sexual partner becomes pregnant. Tell your doctor right away if a pregnancy occurs while you are using these medicines.
  • Your doctor may ask you to have a pregnancy test before you start using this medicine. You must have a negative pregnancy test before you use this medicine with ribavirin. You must use 2 forms of birth control during treatment and for 6 months after treatment ends. You should have a pregnancy test every month while you are using this medicine and for 6 months after your treatment ends.
  • Make sure your doctor knows if you are breastfeeding or if you have kidney disease, liver disease, bleeding problems, lung or breathing problems, heart or blood vessel disease, severe chest pain, a history of a heart attack or stroke, high or low blood pressure, or heart rhythm problems. Tell your doctor if you have thyroid problems, diabetes, vision problems, high triglycerides in the blood, nerve problems, pancreas disease, HIV or AIDS, or an autoimmune disorder (such as psoriasis, lupus, or arthritis).
  • Make sure your doctor knows if you have a history of depression, bipolar disorder, or an addiction to drugs or alcohol. Also, tell your doctor if you have ever had an organ transplant.
  • This medicine can cause mood or behavior changes. Call your doctor right away if you have depression, thoughts of suicide, or any other strange feelings, thoughts, or behaviors.
  • Check with your doctor right away if blurred vision, difficulty with reading, or any other change in vision occurs during or after treatment. Your doctor may want you to have your eyes checked by an eye doctor.
  • This medicine may make you bleed, bruise, or get infections more easily. Take precautions to prevent illness and injury. Avoid people who are ill, and wash your hands often. Brush and floss your teeth gently, do not play rough sports, and be careful with sharp objects.
  • Ask your doctor before you take any medicine to stop severe diarrhea.
  • Serious allergic reactions can occur with this medicine. Check with your doctor right away if you have blistering or peeling skin, fever, chills, rash, or sores or ulcers on the skin while you are using this medicine.
  • Check with your doctor right away if you have sudden and severe stomach pain, constipation, nausea, vomiting, fever, or lightheadedness. These could be symptoms of pancreatitis.
  • Peripheral neuropathy may occur if you use this medicine together with telbivudine (Tyzeka®). Check with your doctor right away if you have burning, numbness, tingling, or painful sensations in the arms, hands, legs, or feet.
  • Your doctor will do lab tests at regular visits to check on the effects of this medicine. 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
  • Blistering, peeling, or red skin rash
  • Bloody or black, tarry stools
  • Chest pain, uneven heartbeat, or trouble breathing
  • Lightheadedness, dizziness, or fainting
  • Numbness, tingling, or burning pain in your hands, arms, legs, or feet
  • Sudden and severe stomach pain, nausea, vomiting, and fever
  • Sudden or severe headache, problems with speech or movement
  • Unusual bleeding, bruising, or weakness
  • Unusual thoughts or behaviors, depression, irritability, or thoughts of hurting yourself or others
  • Yellow skin or eyes

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

  • Changes in vision
  • Diarrhea, constipation, changes in appetite, weight changes, hair loss, or trouble sleeping
  • Dry mouth
  • Fever, chills, cough, runny or stuffy nose, sore throat, or body aches
  • Headache or mild nausea
  • Joint or muscle pain
  • Mild skin rash, redness, itching, or bruising where the shot is given
  • Tiredness

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

Last Updated: 4/4/2014

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