Used to treat chronic hepatitis B virus (HBV) infection in adults and children. It works by reducing the amount of virus in the body, which helps lower liver damage, improves liver function, and reduces the risk of liver complications such as cirrhosis or liver cancer. It is not a cure for HBV but helps control the infection long-term. Typically prescribed for patients with active viral replication and evidence of liver damage. Not effective against hepatitis C or HIV.