Certified Registered Nurse Infusion (CRNI) Practice Exam

Which antiviral agent is known for its ability to inhibit the replication of all known herpes viruses, including CMV?

1. Ganciclovir

2. Acyclovir

3. Foscarnet

4. Valacyclovir

The correct answer is: Foscarnet

Foscarnet is a potent antiviral agent that works by inhibiting viral DNA polymerase, which is crucial for the replication of various herpes viruses, including cytomegalovirus (CMV). This unique mechanism of action makes it particularly effective in cases where other treatments, such as ganciclovir or acyclovir, may not be effective due to resistance or in patients with advanced disease. Foscarnet has a broad spectrum of activity against herpes viruses, making it a valuable option for treating infections caused by these viruses, particularly in immunocompromised patients where CMV can pose significant health risks. Its ability to inhibit the replication of multiple herpes virus strains contributes to its clinical utility in managing these infections, especially when other antiviral therapies are inadequate. Other options listed, while effective against certain herpes viruses, do not have the same broad effectiveness against all known herpes viruses. Ganciclovir, for instance, is primarily effective against CMV, while acyclovir and valacyclovir are more selectively effective against herpes simplex virus and varicella-zoster virus.