What is this medicine?

PEGINTERFERON ALFA-2a (peg in ter FEER on AL fa 2 a) is a man-made drug that acts like a protein made by the body. It is used to treat chronic hepatitis B and C infections.

This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

COMMON BRAND NAME(S): Pegasys, Pegasys ProClick

What should I tell my health care provider before I take this medicine?

They need to know if you have any of these conditions:

  • alcoholism
  • auto-immune hepatitis
  • blood or bleeding disorders
  • colitis like ulcerative colitis or Crohn's disease
  • depression or other mental disorders
  • diabetes
  • drug abuse or addiction
  • heart disease
  • history of cancer
  • kidney disease
  • lupus
  • psoriasis
  • rheumatoid arthritis
  • thyroid problems
  • an unusual or allergic reaction to peginterferon, other medicines, foods, dyes, or preservatives like benzyl alcohol
  • pregnant or trying to get pregnant
  • breast-feeding

How should I use this medicine?

This medicine is for injection under the skin. Do NOT shake this medicine. You will be taught how to prepare and give this medicine. Use exactly as directed. Take your medicine at regular intervals. Do not take your medicine more often than directed.

It is important that you put your used needles and syringes in a special sharps container. Do not put them in a trash can. If you do not have a sharps container, call your pharmacist or healthcare provider to get one.

A special MedGuide will be given to you by the pharmacist with each prescription and refill. Be sure to read this information carefully each time.

Talk to your pediatrician regarding the use of this medicine in children. While this drug may be prescribed for children as young as 3 years for selected conditions, precautions do apply.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

If you miss a dose and you remember within 2 days of when you missed your dose, take it as soon as you can. If it is late in the day, wait until the next day to take your dose. If more than 2 days have passed since you missed your dose ask your doctor what to do. Do not take double or extra doses.

What may interact with this medicine?

  • alcohol
  • medicines for HIV like didanosine, lamivudine, stavudine, zidovudine
  • methadone
  • theophylline

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medicine?

Visit your doctor or health care provider for regular checks on your progress. You will need regular blood checks.

This medicine may cause serious skin reactions. They can happen weeks to months after starting the medicine. Contact your health care provider right away if you notice fevers or flu-like symptoms with a rash. The rash may be red or purple and then turn into blisters or peeling of the skin. Or, you might notice a red rash with swelling of the face, lips or lymph nodes in your neck or under your arms.

You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medicine affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells. Alcohol may interfere with the effect of this medicine. Avoid alcoholic drinks.

This medicine may increase blood sugar. Ask your health care provider if changes in diet or medicines are needed if you have diabetes.

What side effects may I notice from receiving this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:

  • allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
  • bloody diarrhea
  • breathing problems
  • changes in vision
  • chest pain
  • confusion, trouble speaking or understanding
  • fast, irregular heartbeat
  • fever
  • high blood pressure
  • increased anger, depression, irritability, or thoughts of suicide
  • pain in lower back or stomach
  • pain, tingling, numbness in the hands or feet
  • redness, blistering, peeling or loosening of the skin, including inside the mouth
  • signs and symptoms of high blod sugar such as being more thirsty or hungry or having to urinate more than normal. You may also feel very tired or have blurry vision.
  • sudden numbness or weakness of the face, arm or leg
  • trouble passing urine
  • trouble walking, dizziness, loss of balance or coordination
  • unusual bleeding or bruising

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

  • aches, pains
  • dry, itchy skin
  • hair loss
  • loss of appetite
  • nausea, stomach upset
  • pain or swelling at site where injected
  • trouble sleeping
  • unusually weak or tired

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Where should I keep my medicine?

Keep out of the reach of children.

Store in a refrigerator between 2 and 8 degrees C (36 and 46 degrees F). Do not freeze. Protect from light. Do not leave this medicine out of the refrigerator for more than 24 hours. Throw away any unused medicine after the expiration date.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

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