It is possible to consider switching to entecavir after eight years of adefovir, although adjustments need to be made under the guidance of a specialist.
Taking adefovir for a long period of time may cause the emergence of drug resistance, in which case it can be replaced with less resistant antiviral drugs, such as nucleotide analogs, of which entecavir is one, under the guidance of a specialist.
After replacing adefovir with entecavir, patients are required to have liver function tests, liver and biliary ultrasound, and hepatitis B virus DNA quantification once every 3 months to avoid liver function abnormalities.
Adverse effects of adefovir include headache, nausea, diarrhea, abdominal pain, and dyspepsia, and are contraindicated in those who are allergic to adefovir; adverse effects of entecavir include nausea, headache, dizziness, and fatigue, and are contraindicated in those who are allergic to entecavir.
In addition, the application of the above drugs have certain risks, patients need to get the guidance of a specialist, do not be negligent, so as not to delay the condition.