Medication Pearl of the Day: Ganciclovir ophthalmic gel (Zirgan)
Indication: Ganciclovir ophthalmic gel (Zirgan) is a topical ophthalmic antiviral that is indicated for the treatment of acute herpetic keratitis (dendritic ulcers).
Insight
- Dosing: The recommended dosing regimen for Zirgan is 1 drop in the affected eye, 5 times per day (approximately every 3 hours while awake) until the corneal ulcer heals, and then 1 drop 3 times per day for 7 days.
- Dosage forms: Zirgan contains 0.15% of ganciclovir in a sterile preserved topical ophthalmic gel.
- Adverse events: Most common adverse reactions reported in patients were blurred vision (60%), eye irritation (20%), punctate keratitis (5%), and conjunctival hyperemia (5%).
- Mechanism of action: Zirgan contains the active ingredient, ganciclovir, which is a guanosine derivative that, upon phosphorylation, inhibits DNA replication by herpes simplex viruses. Ganciclovir is transformed by viral and cellular thymidine kinases to ganciclovir triphosphate, which works as an antiviral agent by inhibiting the synthesis of viral DNA in 2 ways: competitive inhibition of viral DNA-polymerase and direct incorporation into viral primer strand DNA, resulting in DNA chain termination and prevention of replication.
- Manufacturer: Bausch + Lomb
Sources
zirganpackageinsert.pdf (zirganpro.com)
zirgan image - Google Search