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Peginterferon Alfa-2b (Injection)

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

Treats hepatitis C.

Brand Name(s):

PEGIntron, Peg Intron RP, Sylatron

There may be other brand names for this medicine.

When This Medicine Should Not Be Used:

This medicine is not right for everyone. You should not receive this medicine if you had an allergic reaction to peginterferon alfa-2b, or if you have autoimmune hepatitis. You should not receive this medicine together with ribavirin if you had an allergic reaction to ribavirin, or if you are pregnant, your sexual partner is pregnant, or you have a blood disorder such as sickle-cell anemia or thalassemia major.

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.
  • 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.
  • This medicine comes in a glass vial or prefilled syringe. You might not use all of the medicine in each vial or syringe. Use each vial or syringe one time. Do not save an open vial or syringe. If the medicine has changed color or has particles in it, do not use it.
  • If you switch from using the glass vial to the prefilled syringe, make sure that you are giving yourself the correct amount of medicine.
  • 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.
  • This medicine should come with a Medication Guide. Ask your pharmacist for a copy if you do not have one.
  • Missed dose: You must use this medicine on a fixed schedule. Call your doctor or pharmacist if you miss a dose.
  • 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.
  • Throw away used needles in a hard, closed container that the needles cannot poke through. Keep this container away from children and pets.

Drugs and Foods to Avoid:

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

  • Some medicines can affect how peginterferon alfa-2b works. Tell your doctor if you are using any of the following:
    • a blood thinner (such as warfarin)
    • medicine to treat HIV or AIDS (didanosine, lamivudine, stavudine, zidovudine)
    • flecainide
    • methadone
    • phenytoin
    • telbivudine

Warnings While Using This Medicine:

  • This medicine may cause birth defects if either partner is using it together with ribavirin during conception or pregnancy. Tell your doctor right away if you or your partner becomes pregnant.
  • A negative pregnancy test is required for women who are of childbearing age before starting combination therapy with ribavirin. Female patients and female partners of male patients must use 2 forms of birth control during treatment and for 6 months after treatment ends. Female patients must have regular pregnancy tests during combination therapy.
  • Tell your doctor if you are breastfeeding, or if you have kidney disease, liver disease, bleeding problems, lung or breathing problems (such as COPD), heart or blood vessel disease, severe chest pain, a history of a heart attack or stroke, high or low blood pressure, heart rhythm problems, diabetes, thyroid problems, vision problems, high triglyceride levels, pancreas disease, HIV or AIDS, or an autoimmune disorder (such as psoriasis, lupus, or arthritis). Tell your doctor if you have a history of depression, bipolar disorder, or addiction to drugs or alcohol. Also tell your doctor if you have ever had an organ transplant.
  • This medicine may cause the following problems:
    • Depression, suicidal thoughts, or aggressive behavior
    • Heart problems
    • New or worsening diabetes, thyroid problems, or autoimmune disorders
    • New or worsening lung or liver problems
    • Inflammation of the pancreas or intestines
    • Vision changes or eye problems
    • Serious allergic reactions (that can be life-threatening)
    • Teeth and gum problems
    • Slowed growth in children
  • This medicine may make you bleed, bruise, or get infections more easily. Take precautions to prevent illness and injury. Wash your hands often.
  • This medicine can cause diarrhea. Call your doctor if the diarrhea becomes severe, does not stop, or is bloody. Do not take any medicine to stop diarrhea until you have talked to your doctor. Diarrhea can occur 2 months or more after you stop taking this medicine.
  • Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.
  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

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 or trouble breathing
  • Dark urine or pale stools, nausea, vomiting, loss of appetite, stomach pain, yellow skin or eyes
  • Fast, slow, pounding, or uneven heartbeat
  • Fever, chills, cough, runny or stuffy nose, sore throat, body aches
  • 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
  • Vision changes

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

  • Diarrhea, constipation, changes in appetite, weight changes
  • Hair loss
  • Headache
  • Mild skin rash, redness, itching, or bruising where the shot was given
  • Tiredness, joint or muscle pain
  • Trouble sleeping or anxiety

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: 11/4/2014
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