Which topical antiviral is commonly used for HSV keratitis in addition to or instead of trifluridine?

• A. Ganciclovir
• B. Acyclovir
• C. Foscarnet
• D. Idoxuridine

Answer: (A)

Treating HSV keratitis topically is about delivering a potent anti-HSV effect with minimal damage to the corneal surface. Ganciclovir gel fits this goal well because it is activated in infected cells and then inhibits viral DNA polymerase, effectively stopping HSV replication. It works against both HSV-1 and HSV-2 and is generally better tolerated by the corneal epithelium than trifluridine, making it a common alternative or add‑on when trifluridine is used. Dosing is typically a drop five times daily until healing, then taper. Acyclovir is more commonly used systemically for HSV keratitis and only occasionally topical; foscarnet is reserved for acyclovir‑resistant cases, and idoxuridine is an older, more toxic option with limited use today. So, ganciclovir is the best topical choice besides trifluridine.