The active ingredient of any brand of entecavir is entecavir, which has good effect in the treatment of hepatitis B. The medication should be used according to the doctor’s prescription. The commonly used dosage forms of Entecavir are dispersible tablets, capsules, etc. It has an inhibitory effect on hepatitis B virus polymerase. It is used for the treatment of chronic hepatitis B in people aged 2 years and above who have active viral replication, persistent elevation of alanine aminotransferase, or histology showing active lesions. In clinical application this product can effectively reduce the viral load and slow down the progression of the disease with good results. However, the efficacy exists from person to person, due to the degree of disease, the degree of sensitivity to the drug and other differences will affect the effectiveness of the drug. Adverse reactions such as diarrhea, nausea, dyspepsia, vomiting, fatigue, headache, dizziness, insomnia or drowsiness can be seen with this product. It is contraindicated for those who are allergic to this product. The use of this product to treat the disease, should be under the guidance of a doctor to rationalize the use of medication.