Peginterferon Alfa-2a (By injection)

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

Treats hepatitis B or hepatitis C.

Brand Name(s):

Pegasys

There may be other brand names for this medicine.

When This Medicine Should Not Be Used:

This medicine is not right for everyone. Do not use it if you had an allergic reaction to peginterferon alfa-2a.

How to Use This Medicine:

Injectable

  • 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. It is usually given in the upper thighs or stomach.
  • A nurse or other health provider will give you this medicine.
  • 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.
  • 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.
  • This medicine is available in 2 forms: vial and prefilled syringe.
  • Prefilled syringe:
    • Wash your hands with soap and water before and after using this medicine.
    • Check the liquid in the syringe. It should be clear and colorless to light yellow. Do not use it if it is cloudy or has particles in it. If there is foam, put it back in the refrigerator for later use.
    • Allow the syringe to warm to room temperature.
    • Remove and throw away the rubber cap from the tip of the syringe barrel.
    • With one hand, hold the syringe by the barrel. With your other hand, hold the needle close to the hub where the green needle cover connects to the syringe.
    • Push the needle onto the syringe and tighten by using an easy twisting motion in the direction of the arrow.
    • Pull the green needle cover back from the needle toward the syringe barrel. Do not remove it.
    • Hold the syringe and needle tightly. Gently rock the plastic needle shield back and forth for removal. Remove the plastic needle shield by pulling it straight off.
    • If you see large air bubbles in the syringe, hold the syringe with the needle pointing up and tap the syringe to bring air bubbles to the top. Press the plunger in slightly to push air bubbles out of the syringe.
    • Pinch the skin firmly between your thumb and forefinger. Hold the syringe like a pencil at a 45 to 90 degree angle to your skin. With a quick "dart-like" motion, push the needle into the skin as far as it will go.
    • Gently push the plunger rod all the way down until empty.
  • Vial:
    • Wash your hands with soap and water before and after using this medicine.
    • Check the liquid in the vial. It should be clear and colorless to slightly yellowish. Do not use it if it is cloudy or has particles in it.
    • Allow the vial to warm by gently rolling it in the palms of your hands for 1 minute. Do not shake.
    • Remove the plastic cap from the top of the vial. Clean the rubber stopper.
    • Remove the needle cap. Fill the syringe with air by pulling back on the plunger to the mark on the syringe barrel that matches the prescribed dose.
    • Hold the vial on a flat surface. Do not touch the cleaned rubber stopper. Push the needle straight down through the middle of the rubber stopper on the vial. Slowly inject all the air from the syringe into the air space above the solution. Do not inject air into the fluid.
    • Keep the needle in the vial. Turn the vial upside down. Slowly pull back on the plunger to fill the syringe with the medicine to the prescribed dose.
    • Do not remove the needle from the vial. Lay the vial and syringe on its side on your flat work surface until you are ready to inject.
    • If you see large air bubbles in the syringe, hold the syringe with the needle pointing up and tap the syringe to bring air bubbles to the top. Press the plunger in slightly to push air bubbles out of the syringe.
    • Pinch the skin firmly between your thumb and forefinger. Hold the syringe like a pencil at a 45 to 90 degree angle to your skin. With a quick "dart-like" motion, push the needle into the skin as far as it will go.
    • Gently push the plunger rod all the way down until empty.
  • 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:
    • Fewer than 2 days late: Use your medicine as soon as you can, then go back to your regular schedule the next week.
    • More than 2 days late: Call your doctor for instructions.
    • Do not use extra medicine to make up for a missed dose.
  • If you store this medicine at home, keep it in the refrigerator. Do not freeze. Do not leave this medicine out of the refrigerator for more than 24 hours. Protect it from light.

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-2a works. Tell your doctor if you are using azathioprine, methadone, telbivudine, theophylline, or medicines to treat HIV or AIDS (including zidovudine).
  • Do not drink alcohol while you are using this medicine.

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. Female patients and female partners of male patients must use 2 forms of birth control during treatment with these medicines and for 6 months after the last dose. Female patients must have regular pregnancy tests during combination treatment.
  • Tell your doctor if you are breastfeeding, or if you have kidney disease, other liver disease, diabetes, thyroid problems, an autoimmune disorder (including psoriasis, lupus, or arthritis), bleeding problems, heart or blood vessel disease, heart rhythm problems, or high blood pressure. Tell your doctor if you have a history of heart attack, stroke, cancer, depression, or drug addiction.
  • This medicine may cause the following problems:
    • Depression or suicidal thoughts
    • Heart problems
    • New or worsening diabetes, thyroid problems, or autoimmune disorders
    • Eye or vision problems
    • Liver problems
    • New or worsening lung problems
    • Increased risk for infection
    • Pancreatitis (swelling of the pancreas)
    • Serious skin reactions
    • Slowed growth in children
    • Peripheral neuropathy (nerve problem)
  • 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.
  • This medicine may make you dizzy or drowsy. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.
  • You could still give hepatitis B or hepatitis C to other people while you are using 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 severe diarrhea
  • Chest pain that may spread to your arms, jaw, back, or neck, trouble breathing, unusual sweating, faintness
  • Fast, slow, pounding, or uneven heartbeat
  • Fever, chills, cough, sore throat, body aches
  • Numbness, tingling, or burning pain in your hands, arms, legs, or feet
  • Sudden and severe stomach pain, nausea, vomiting, lightheadedness
  • Unusual bleeding, bruising, or weakness
  • Unusual thoughts or behaviors, depression, thoughts of hurting yourself or others
  • Vision changes, blurred vision, trouble reading, eye pain

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

  • Hair loss
  • Mild diarrhea, nausea, or vomiting
  • Mild flu-like symptoms, including muscle aches, headache, low fever, or tiredness
  • Redness, pain, itching, or bruising where the shot was given

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: 9/6/2024

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