Hepatitis B dna quantification <500 after eating entecavir can be considered clinically cured. 1. Clinical cure: Hepatitis B DNA quantitative less than 500, this situation indicates that the patient body’s viral load is very low, which means that the condition is relatively stable, and there are no obvious complications, to achieve the standard of clinical cure, but you need to continue to take drugs to consolidate the treatment. 2. Basic cure: that is to say, the E antigen and nucleic acid of hepatitis B virus of the patient’s body become negative, and at the same time, the liver function is normal, and there is no symptom of cirrhosis in ultrasound examination. 3. Complete cure: that is, the surface antigen of hepatitis B disappears completely. However, chronic hepatitis B is still a disease that cannot be cured by drugs, and it is often difficult to reach this standard. Common adverse reactions to entecavir include headache, fatigue, dizziness, and nausea, etc. It is contraindicated for those who are allergic to entecavir. In addition, the use of entecavir carries certain risks and patients need to be guided by a specialist.