Key takeaways
Abacavir (Ziagen) and entecavir (Baraclude) are both nucleoside reverse transcriptase inhibitors (NRTIs) used to treat viral infections, but they target different viruses. Abacavir is used for HIV treatment, while entecavir is used for hepatitis B. Abacavir requires a genetic test before starting due to the risk of a severe allergic reaction, whereas entecavir does not. Abacavir is available in both tablet and oral solution forms and can be taken with or without food, while entecavir is available as a tablet and liquid solution but must be taken on an empty stomach. Abacavir is available as a generic, while only the tablet form of entecavir has a generic version. Common side effects of abacavir include headache, nausea, fatigue and rash, while entecavir may cause headache, fatigue, dizziness and higher liver lab results. Abacavir has fewer drug interactions but requires caution in people with heart or severe liver problems, whereas entecavir requires dose adjustments for those with kidney issues.
