Which statement describes the dosing for Trifluridine and Ganciclovir as topical antivirals?

Which statement describes the dosing for Trifluridine and Ganciclovir as topical antivirals?

• A. Trifluridine is dosed 9x daily; Ganciclovir is dosed 5x daily
• B. Both are dosed 9x daily
• C. Ganciclovir is dosed 9x daily; Trifluridine is dosed 5x daily
• D. Both are dosed once daily

Answer: (A)

Dosing frequency for topical ocular antivirals is shaped by how long the drug stays effective on the eye and how well the eye tolerates it. Trifluridine needs very frequent application—about nine times per day—to keep antiviral levels high because the tear film turnover rapidly clears the drug and it can irritate the cornea if not kept in contact. Ganciclovir gel, while still active against herpesviruses, is generally better tolerated and has a longer duration of action in the tear film, so it can be given less often—about five times daily—while still delivering the needed exposure. In practice, trifluridine is used roughly every two hours while awake in the initial days, then tapered, whereas ganciclovir gel is prescribed five times daily for about a week with a subsequent taper.

Dosing frequency for topical ocular antivirals is shaped by how long the drug stays effective on the eye and how well the eye tolerates it. Trifluridine needs very frequent application—about nine times per day—to keep antiviral levels high because the tear film turnover rapidly clears the drug and it can irritate the cornea if not kept in contact. Ganciclovir gel, while still active against herpesviruses, is generally better tolerated and has a longer duration of action in the tear film, so it can be given less often—about five times daily—while still delivering the needed exposure. In practice, trifluridine is used roughly every two hours while awake in the initial days, then tapered, whereas ganciclovir gel is prescribed five times daily for about a week with a subsequent taper.