Which antiviral is appropriate for episodic treatment of oral herpes?

Which antiviral is appropriate for episodic treatment of oral herpes?

• A. Aciclovir
• B. Valaciclovir
• C. Famciclovir
• D. Ganciclovir

Answer: (A)

Treating an episode of oral herpes relies on stopping viral replication quickly with an antiviral that is selectively activated in infected cells. Aciclovir fits this role well because it’s a guanosine analogue activated by the herpes simplex virus thymidine kinase. Once activated, it inhibits viral DNA polymerase and terminates DNA chain growth, reducing viral replication specifically in HSV-infected cells. When started at the onset of an outbreak, this mechanism translates into faster healing and less pain. For episodic oral herpes, a common regimen is 400 mg taken five times daily for five days, a schedule that offers strong efficacy with a favorable safety profile. Its long-standing use means clinicians have solid experience with its effectiveness, tolerability, and cost, making it a reliable first‑line option. Valaciclovir and famciclovir are also effective and convenient because they are prodrugs with better oral bioavailability, allowing simpler dosing while delivering similar antiviral activity. They’re appropriate alternatives, but aciclovir remains a classic, widely used choice, especially where cost or accessibility is a priority. Ganciclovir, while active against HSV, is less favored for episodic orolabial herpes due to greater toxicity and its primary indication is CMV infections rather than HSV outbreaks.

Treating an episode of oral herpes relies on stopping viral replication quickly with an antiviral that is selectively activated in infected cells. Aciclovir fits this role well because it’s a guanosine analogue activated by the herpes simplex virus thymidine kinase. Once activated, it inhibits viral DNA polymerase and terminates DNA chain growth, reducing viral replication specifically in HSV-infected cells. When started at the onset of an outbreak, this mechanism translates into faster healing and less pain. For episodic oral herpes, a common regimen is 400 mg taken five times daily for five days, a schedule that offers strong efficacy with a favorable safety profile. Its long-standing use means clinicians have solid experience with its effectiveness, tolerability, and cost, making it a reliable first‑line option.

Valaciclovir and famciclovir are also effective and convenient because they are prodrugs with better oral bioavailability, allowing simpler dosing while delivering similar antiviral activity. They’re appropriate alternatives, but aciclovir remains a classic, widely used choice, especially where cost or accessibility is a priority. Ganciclovir, while active against HSV, is less favored for episodic orolabial herpes due to greater toxicity and its primary indication is CMV infections rather than HSV outbreaks.