Acivir cream contains acyclovir as its active ingredient. Acyclovir is a nucleoside analogue antiviral drug. It works by inhibiting viral DNA polymerase, a key enzyme herpes simplex viruses (HSV) and varicella-zoster viruses (VZV) need to replicate. Specifically, acyclovir is phosphorylated by viral thymidine kinase into acyclovir monophosphate. This is further phosphorylated by cellular kinases to acyclovir triphosphate, a potent inhibitor of viral DNA polymerase.
Targeting Viral Replication
Acyclovir triphosphate competes with deoxyguanosine triphosphate (dGTP), a natural substrate for viral DNA polymerase. Incorporation of acyclovir triphosphate into the viral DNA chain terminates further elongation and prevents viral replication. This targeted mechanism minimizes harm to the host cells, as human cells lack the viral thymidine kinase needed for the initial phosphorylation step. This selective action contributes to the cream’s efficacy in treating herpes simplex virus infections.
Clinical Implications
This mechanism explains Acivir cream’s effectiveness in reducing the duration and severity of herpes simplex virus outbreaks. It’s crucial to remember that acyclovir does not cure the virus; it only manages symptoms and reduces viral shedding.
