From the Guidelines
The initial treatment for herpes keratitis should be topical antiviral medication, specifically ganciclovir 0.15% gel used three to five times per day or trifluridine 1% solution five to eight times per day, as these options are effective in treating the condition while minimizing toxicity to the ocular surface. When considering treatment options, it's crucial to weigh the potential benefits and risks, including the fact that topical trifluridine can cause epithelial toxicity if used for more than 2 weeks, whereas topical ganciclovir is less toxic 1. Key points to consider in the management of herpes keratitis include:
- The use of oral antivirals such as acyclovir (200 to 400 mg five times per day), valacyclovir (500 mg two or three times per day), or famciclovir (250 mg twice a day) for more extensive disease or when there's a high suspicion of corneal involvement 1.
- Avoiding topical corticosteroids, as they can potentiate HSV infection and worsen the condition 1.
- The importance of follow-up within 1 week of treatment to assess the response to therapy and adjust the treatment plan as necessary, including an interval history, visual acuity measurement, and slit-lamp biomicroscopy 1. In clinical practice, the choice of treatment should prioritize minimizing morbidity, mortality, and improving quality of life, which in the case of herpes keratitis, involves effective and timely antiviral therapy to prevent complications such as corneal scarring or decreased vision.
From the FDA Drug Label
ZIRGAN is a topical ophthalmic antiviral that is indicated for the treatment of acute herpetic keratitis (dendritic ulcers). 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.
The initial treatment for herpes keratitis is topical ophthalmic antiviral medication, specifically ganciclovir ophthalmic gel 0.15%. The recommended dosing regimen is:
- 1 drop in the affected eye 5 times per day (approximately every 3 hours while awake) until the corneal ulcer heals
- Then, 1 drop 3 times per day for 7 days 2
From the Research
Initial Treatment for Herpes Keratitis
The initial treatment for herpes keratitis typically involves the use of antiviral agents. Some of the commonly used treatments include:
- Topical trifluridine
- Topical acyclovir
- Topical ganciclovir
- Topical vidarabine
Comparison of Treatments
Studies have compared the efficacy of these treatments, with some findings including:
- Ganciclovir 0.15% gel being at least as effective as acyclovir 0.3% ointment for the treatment of HSV keratitis, with better tolerability 3, 4, 5
- Trifluridine and acyclovir being significantly more effective than idoxuridine for dendritic epithelial keratitis 6
- Vidarabine being equivalent to trifluridine and acyclovir in terms of effectiveness 6
Treatment Characteristics
Some key characteristics of these treatments include:
- Ganciclovir having selective pharmacologic activity on viral thymidine kinase, resulting in lower potential for toxicity to healthy human cells 3, 4
- Acyclovir being a more selective agent than earlier generation drugs, with lower bioavailability and local cellular toxicity 3
- Topical interferon being used in combination with antiviral agents to speed epithelial healing 6
Clinical Trials and Studies
Numerous clinical trials and studies have been conducted to evaluate the efficacy and safety of these treatments, including:
- A systematic review of published randomized clinical trials for HSV epithelial and stromal keratitis 7
- Multicenter randomized clinical trials comparing ganciclovir gel to acyclovir ointment for the treatment of HSV keratitis 3, 4, 5
- A meta-analysis of treatment trials for dendritic epithelial keratitis 6