What medication treats herpes simplex viruses and shingles?

Acyclovir is an antiviral medication specifically designed to treat infections caused by certain types of viruses, including herpes simplex viruses (HSV) and varicella-zoster virus (which causes shingles). Acyclovir works by inhibiting the replication of viral DNA, making it effective in reducing the severity and duration of outbreaks related to these viruses.

When treating herpes simplex, acyclovir can help manage and alleviate symptoms during active outbreaks, while also serving as a preventative measure in individuals with frequent recurrences. In the case of shingles, acyclovir can significantly aid in reducing pain and the duration of the virus's activity.

Other medications listed either target different viruses or do not have the broad antiviral spectrum provided by acyclovir. For instance, docosanol is primarily used as a topical treatment for cold sores but is not effective against shingles. Zidovudine is mainly utilized for the treatment of HIV and does not specifically target herpes viruses. Famciclovir is another antiviral that treats herpes virus infections, but acyclovir remains the more recognized first-line treatment for these conditions, which solidifies it as the correct choice in this context.