<s>[INST] I am taking entecavir (baraclude) during the last four years ( 0.5mg/day). I. m a 61 year old man with a very good health except for being HbsAg positive. Normal liver funcion. After that Im lost 80% of my erection . All my hormones test are norma Entecavir, itself could be in cause of these problem? Thank you carlos Cesa filho [/INST] Hi,Thanks for posting your query.You are having erectile dysfunction.Erectile dysfunction is not a known side effect of entecavir.It could be part of aging process or due to organic causes like diabetes.Consult an urologist/endocrinologist for evaluation of your erectile dysfunction.I hope that answers your question.Regards. </s>