What is the main action of antiviral medications like acyclovir?

The primary mechanism of antiviral medications like acyclovir is to inhibit viral replication. Acyclovir is specifically designed to interfere with the replication process of certain viruses, particularly herpes simplex virus (HSV) and varicella-zoster virus (VZV). It works by mimicking a nucleoside, which allows it to be incorporated into the viral DNA during replication. This incorporation leads to chain termination and prevents the virus from multiplying effectively, thereby reducing the viral load in the body.

While some antiviral medications may influence the immune response or work to prevent the spread of viruses, those strategies are not the main action of acyclovir. The direct "killing" of viruses is not an accurate description of acyclovir's action; instead, it is crucial to understand that antiviral agents primarily act by targeting the replication machinery of the viruses to limit their ability to proliferate.