Table of Contents
Common side effects include flu-like symptoms, such as fever, chills, muscle aches, joint pains, and headaches. The drug can also cause depression, anxiety, irritability, and insomnia and should be used with caution in patients with a history of mental illness. Peginterferon alfa-2a can also increase the risk for infections, and worsening of hepatitis as marked by sudden severe increases in ALT levels. Patients who show signs of ALT flares should have frequent blood tests to monitor their liver function.
Unlike other drugs used to treat chronic hepatitis B, drug resistance is less of a problem with peginterferon alfa-2a.
Interferon Alfa-2b. For many years, interferon alfa-2b (Intron A) was the standard drug for hepatitis B. It is now generally second line to peginterferon The drug is usually taken by injection every day for 16 weeks. Unfortunately, even in hepatitis B, the virus recurs in almost all cases, although this recurring mutation may be weaker than the original strain. Administering the drug for longer periods may produce sustained remission in more patients while still being safe. Interferon is also effective in eligible children, although long-term effects are unclear. Like peginterferon alfa-2a, this drug can increase the risk of depression.
Lamivudine, Entecavir, and Telbivudine. These drugs are classified as nucleoside analogs. Lamivudine (Epivir-HBV) is also used in another formulation to treat human immunodeficiency virus (HIV). About 20% of patients who take lamivudine develop drug resistance. Lamivudine, along with interferon alfa-2b, are the only drugs approved for treatment of chronic hepatitis B in children. Entecavir (Baraclude) and telbivudine (Tyzeka) are approved for treatment of adults with chronic hepatitis B.
If patients develop resistance to one of these nucleoside analog drugs, a nucleotide-analog drug such as adefovir or tenofovir may be added as combination therapy. Lamivudine is associated with the highest rate of drug resistance. Entecavir and tenofovir have the lowest likelihood of drug resistance.
Common side effects of these drugs include headache, fatigue, dizziness, and nausea. (For more serious side effects, see "Drug Complications and Warnings" below.)
Adefovir and Tenofovir. Adefovir (Hepsera) is an older drug that belongs to a class of antiviral drugs called nucleotide analogs. Nucleotide analogs block an enzyme involved in the replication of viruses. Tenofovir (Viread) is a newer nucleotide analog drug that is now preferred over adefovir. These drugs are effective against lamivudine-resistant strains of hepatitis B. Common side effects of these drugs include weakness, headache, stomach pain, and itching.
Drug Complications and Warnings for Nucleoside/Nucleotide Analog Drugs. Patients who discontinue anti-HBV drug therapy are at risk for severe and sudden worsening of hepatitis. These patients should be closely monitored for several months after stopping treatment. If necessary, drug treatment may need to be reinstated.
Lactic acidosis (buildup of acid in the blood) is a serious complication of nucleoside/nucleotide analog drugs. Signs and symptoms of lactic acidosis include feeling extremely tired, unusual muscle pain, difficulty breathing, stomach pain with nausea and vomiting, feeling cold (especially in the arms and legs), feeling dizzy or light-headed, or a fast or irregular heartbeat. Immediately contact your doctor if you experience these symptoms.
Liver hepatotoxicity (liver damage) is another serious complication. Signs and symptoms include yellowing of skin or white part of eyes (jaundice), dark urine, light-colored stool, or lower stomach pain. Immediately contact your doctor if you experience these symptoms.
Previous Section
Review Date: 09/29/2010
Reviewed By: Harvey Simon, MD, Editor-in-Chief, In-Depth Reports; Associate
Professor of Medicine, Harvard Medical School; Physician,
Massachusetts General Hospital. Also reviewed by David Zieve, MD,
MHA, Medical Director, A.D.A.M., Inc.
A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org)
