I. What is relapse? In the course of chronic hepatitis B treatment, the application of antiviral drugs (lamivudine, adefovir, entecavir, telbivudine) is stopped when the conditions for stopping the drugs are met, i.e. (the major triple positive is changed to the minor triple positive, the liver function returns to normal, and the DNA of hepatitis B turns to be negative) and the drugs are stopped. After stopping the drug and continuing observation, it is found that some patients have DNA positive again with or without liver function abnormality, which is called relapse, and it is necessary to continue antiviral treatment. Second, what is drug resistance, in the process of chronic hepatitis B treatment, using antiviral drugs (lamivudine, adefovir, entecavir, tibivudine, etc.), in the process of continuous use of medication, first due to the hepatitis B virus DNA positivity, antiviral after the turn to negative (generally 3 months), and continue to apply the drug, in the process of observation without stopping the medication, the hepatitis B virus DNA is positive again, known as drug resistance (generally occurring after one year of use). (generally appearing after one year of drug use). Third, what is primary drug resistance and secondary drug resistance. Primary drug resistance: clinically, from the beginning of drug treatment to three months, half a year, or one year for individual patients, the DNA of hepatitis B virus of patients is always positive (part of it will be changed from high copy to low copy, but it has never turned negative). Secondary drug resistance: antiviral treatment for 1 to 2 years, first DNA turns negative, continue to use the drug appeared DNA from negative to positive, this situation is called secondary drug resistance. Fourth, how to reduce drug resistance. Clinically, patients with chronic hepatitis B and cirrhosis need to take medication for a longer period of time, in order to avoid the occurrence of drug resistance soon, generally use a combination of drugs, such as Herceptin combined with Hewlett-Packard.