| Click on "►" to expand:|
[×] Entry inhibitors
 BRAND NAMES
- International: Zovirax
- Italy: Zovirax, Acy
 MECHANISM OF ACTION
Acyclovir is an acyclic guanine nucleoside analogue.
Acyclovir is phosphorylated by viral thymidine kinase to acyclovir monophosphate, the aciclovir affinity to viral thymidine kinase is much greater than for human thymidine kinase and therefore the phosphorylation reaction occurs more rapidly in cells infected with herpes virus than in normal cells.
Subsequently Acyclovir monophosphate is further converted to diphosphate and triphosphate by cellular enzymes.
Acyclovir-triphosphate enters in competition with deoxyguanosine triphosphate, and it's incorporation into viral DNA prevents DNA chain elongation due to the lack of 3'-hydroxyl group. The terminated DNA template containing acyclovir binds the enzyme and leads to irreversible inactivation of the DNA polymerase.
Herpesviruses encoding the thymidine kinase (herpes simplex and varicella-zoster) are much more sensitive to Acyclovir than those that do not encode it (CMV and Epstein-Barr virus).
Treatment of herpes simplex virus infections of the eye (Keratitis)
Apply the ointment to the inside of the lower eyelid on the affected side five times a day. After application, close your eye for 30 seconds. Treatment should usually be continued for 14 days or at least 3 days after healing is completed.
- hypersensitivity to Acyclovir or valacyclovir.
- Avoid wearing contact lenses
 PREGNANCY AND LACTATION
 SIDE EFFECTS
- Mild stinging immediately after applying the ointment