Combination antiviral therapy for hepatitis C

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Combination antiviral therapy for hepatitis C


Generic NameBrand Name
peginterferon alfa-2a and ribavirinPegasys RBV
peginterferon alfa-2b and ribavirinPegetron

How It Works

Combination antiviral therapy helps prevent the virus that causes hepatitis C from reproducing in the body. Two medicines are generally combined for the best response.

Peginterferon is given as a shot once a week. Ribavirin is taken as a pill 2 times a day. During the course of your treatment, your doctor frequently may adjust the amount of medicine you are taking.

The length of your treatment depends on what hepatitis C genotype you have. Genotype 1 generally is treated for 1 year and genotypes 2 and 3 generally are treated for 6 months. If you have genotype 1 and your viral load does not improve after 3 months of treatment, your treatment may be stopped.

Why It Is Used

Combination antiviral therapy is prescribed for people who have ongoing (chronic) hepatitis C infection. It may be given to people who have never had treatment or when interferon alone has failed to control the disease.

How Well It Works

Peginterferon—a longer-acting form of interferon—combined with ribavirin is better than standard interferon combined with ribavirin. The two kinds of peginterferon work similarly.

How well treatment works is measured by whether you still have the virus in your blood 6 months after treatment. Treatment usually works better if you have genotype 2 or 3 than if you have genotype 1. Most studies have shown that treatment with peginterferon and ribavirin works for up to 50% of people with genotype 1 and up to 80% of people with genotype 2 or 3.2

If you are also infected with HIV, the combination of peginterferon and ribavirin is considered better than standard interferon and ribavirin.4

Combination antiviral therapy is more likely to be effective if you:

  • Have a low level of the hepatitis C virus in your blood when treatment starts.
  • Are infected with genotype 2 or 3.
  • Have a low amount of liver damage when treatment starts.

Many things affect the decision about who should receive antiviral treatment for hepatitis C.1 For example, treatment may be recommended for people who are at least 18 years old, have detectable levels of the virus in their blood, and have significant liver damage confirmed by a liver biopsy.

Side Effects

Side effects from peginterferon and ribavirin are common. If your side effects are severe, you may need to stop treatment. Some side effects may start to go away as treatment continues.

Common side effects of combination antiviral therapy include:

  • Fatigue, headache, muscle and joint aches, fever, or chills.
  • Nausea, loss of appetite, or weight loss.
  • Irritability, insomnia, or confusion.
  • Depression.
  • Thyroid problems.
  • Hair loss or skin rash.
  • Low levels of red cells, white cells, and platelets in your blood.

If you develop anemia as a result of taking ribavirin, your doctor may prescribe a medicine called erythropoietin to help your body create more red blood cells.

Most side effects go away when you stop taking the medicines.

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

You will need regular follow-up visits with a liver specialist during treatment. The specialist will order blood tests to check your liver enzyme levels and to see whether the virus is still present.

People with normal or slightly elevated liver enzyme levels but whose liver biopsy shows little or no liver damage may choose not to have antiviral treatment. Instead, a doctor can monitor the condition with periodic liver function tests and a liver biopsy every 3 to 5 years.

Even if the initial treatment does not eliminate the virus, your doctor may advise you to continue antiviral treatment, because it may reduce liver inflammation. For some people with significant liver damage, antiviral therapy may slow the progression of liver damage or make liver cancer less likely. If you already have cirrhosis, some studies show that antiviral therapy can help you live longer.3

If it is possible that you are pregnant, you will need a pregnancy test. Women and men who are taking ribavirin need to avoid getting pregnant or fathering a child, because the medicine can damage a developing fetus. Women who could become pregnant and their partners must use two reliable forms of birth control during treatment and for 6 months after treatment, to avoid pregnancy.

Only a few clinical trials have tested antiviral medicines in children. The results suggest that they work about as well in children as in adults.

If you are obese or have diabetes, you may need to delay treatment until you get your weight or blood sugar under control.

If you have tried interferon in the past and did not get good results, talk to your doctor about newer combinations of peginterferon with ribavirin or any new, experimental treatments.

The long-term health effects of combination antiviral therapy are not known at this time.

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  1. Management of hepatitis C: 2002. Consensus Development Conference statement, National Institutes of Health Consensus Development Conference (2002 June 10–12). NIH Consensus Development Program. Available online:
  2. Ward RP, et al. (2004). Management of hepatitis C: Evaluating suitability for drug therapy. American Family Physician, 69(6): 1429–1438.
  3. Dienstag JL (2010). Chronic viral hepatitis. In GL Mandell et al., eds., Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases, 7th ed., vol. 1, pp. 1593–1670. Philadelphia: Churchill Livingstone Elsevier.
  4. Chung RT, et al. (2004). Peginterferon alfa-2a plus ribavirin versus interferon alfa-2a plus ribavirin for chronic hepatitis C in HIV-coinfected persons. New England Journal of Medicine, 351(5): 451–459.


By Healthwise Staff
Primary Medical Reviewer Kathleen Romito, MD - Family Medicine
Specialist Medical Reviewer W. Thomas London, MD - Hepatology
Specialist Medical Reviewer Donald Sproule, MD, CM, CCFP, FCFP - Family Medicine
Last Revised October 9, 2009

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