Antiviral medication for hepatitis B is usually required for many years, sometimes for a lifetime. A small number of severely ill patients may need a liver transplant, which involves replacing a diseased liver with a healthy one. Additionally, patients may also be advised to undergo ultrasound (which images the inside of the body) every 6 months to determine the presence or absence of liver cancer. The optimal course of oral medications has not been defined. Most patients treated with nucleoside (acid) analogs will need to be treated for at least 4-5 years, and some may even need to be treated indefinitely. Long-term therapy is especially important for patients with cirrhosis. For patients who do not have cirrhosis or progressive liver fibrosis and who are unable or unwilling to continue lifelong therapy because of the risk or cost of associated adverse events, an attempt to discontinue therapy may be made if they meet the following criteria: HBV DNA undetectable by PCR for > 3 years; and agree to be closely monitored for at least 1 year, i.e., review of liver function once a month for the first 6 months, and testing for HBV DNA every 3 months; and review of liver function and testing for HBV DNA every 3 months for the next 6 months; and review of liver function and testing for HBV DNA every 3 months for the next 6 months. If the patient maintains inactive carrier status, the frequency of monitoring can be reduced to every 6-12 months thereafter.