Hepatitis C is the most common form of chronic hepatitis in the United States, affecting approximately 3.2 million Americans, according to the Centers for Disease Control and Prevention. Therapy with pegylated interferon and ribavirin remains the treatment of choice for chronic hepatitis C for adults and children age 3 and older. Pegylated interferon and ribavirin may cause potentially serious complications. Close monitoring throughout the course of therapy helps detect treatment-related problems early, facilitating appropriate management.
Anemia
Anemia, or a low red blood cell count, is one of the most common complications of interferon plus ribavirin treatment for chronic hepatitis C. Both drugs may contribute to the development of anemia. Ribavirin can cause premature destruction of the red blood cells in the circulation, and interferon may suppress bone marrow production of red blood cells. Up to 20 percent of people on full-dose pegylated interferon plus ribavirin therapy develop treatment-related anemia, reports the National Hepatitis C Program Office of the United States Department of Veterans Affairs. Significant anemia may necessitate a reduction in the daily dose of ribavirin or treatment with medication to stimulate bone marrow production of red blood cells.
Infections
Interferon can suppress bone marrow production of white blood cells, which serve as a primary defense against infections. A significantly depressed white blood cell count, or neutropenia, increases vulnerability to infections. Severe bacterial infections occur in less than 2 percent of patients on interferon plus ribavirin treatment, reports the National Institute of Diabetes and Digestive and Kidney Diseases. Prompt recognition of an infection enables early treatment, reducing the risk for serious and potentially life-threatening complications.
Mental Disturbances
Interferon treatment for chronic hepatitis C can cause depression and other mental disturbances. According to U.S. Food and Drug Administration-approved prescribing information for the two brands of pegylated interferon available in the United States, symptoms of depression occur in approximately 19 to 28 percent of patients during treatment. Common manifestations of treatment-related depression include fatigue, irritability, insomnia and reduced appetite. In extreme cases, patients may experience suicidal thoughts or attempt suicide. Other mental disturbances can also occur with interferon therapy, including aggression, agitation, bizarre behavior and anxiety.
Thyroid Abnormalities
Interferon plus ribavirin therapy for chronic hepatitis C may adversely affect the thyroid gland, causing overproduction or underproduction of thyroid hormones, reports the National Hepatitis C Program Office of the United States Department of Veterans Affairs. This complication develops due to drug-induced immune system stimulation, which can lead to a mistaken attack on the thyroid gland. Monitoring thyroid function during interferon plus ribavirin therapy enables early identification and treatment of medication-related thyroid problems.
References
- Centers for Disease Control and Prevention: Hepatitis C FAQs for Health Professionals
- United States Department of Veterans Affairs: Hepatitis C for Health Care Providers, Interferon and Ribavirin Treatment Side Effects
- National Institute of Diabetes and Digestive and Kidney Diseases: Chronic Hepatitis C: Current Disease Management, Treatment
- Drugs.com: Pegasys FDA Monograph
- Drugs.com: Pegintron FDA Monograph
