The entecavir instructions do not indicate that this product affects sperm quality in men, and there is no research evidence that the drug has an effect on sperm quality, so men taking the drug do not affect having children. Entecavir is a guanine nucleoside analog. It is indicated for the treatment of chronic adult hepatitis B with active viral replication, persistently elevated serum ALT, or liver histology showing active lesions. Entecavir has anti-hepatitis B virus effects and can be used in the treatment of hepatitis B. Self-discontinuation of the drug may cause viral rebound and should not be discontinued on its own. Entecavir adverse reactions can be seen as dyspepsia, diarrhea, nausea, vomiting, fatigue, headache, dizziness, and drowsiness. The drug is contraindicated for those who are allergic to Entecavir or any other ingredients. The drug should be used rationally under the supervision of a doctor.