The difference between pegylated interferon, or pegylated interferon alpha-2b, and entecavir is the mechanism of action and indications. 1. Mechanism of action: Entecavir can have an inhibitory effect on the polymerase of hepatitis B virus, and can also inhibit the activity of type I human immunodeficiency virus strains. Polyethylene glycol interferon alpha-2b inhibits viral replication and cell proliferation in infected cells by binding to cell surface receptors, and also has immunomodulatory effects. 2. Indications: Both can treat chronic hepatitis B, but PEGylated Interferon α-2b can also be used in the treatment of chronic hepatitis C. Polyethylene glycol interferon alpha-2b adverse reactions can be seen headache, dizziness, fatigue, arthralgia, decreased appetite, nausea, alopecia and so on. It is contraindicated in people who are allergic to the product, autoimmune chronic hepatitis, severe hepatic dysfunction, decompensated cirrhosis, history of severe heart disease, severe psychiatric disorders, pregnancy and breastfeeding. Entecavir adverse reactions include fatigue, headache, dizziness and nausea. It is contraindicated in people who are allergic to the product. The drug needs to be used appropriately under the supervision of a doctor.