Herpetic keratitis is caused by herpes simplex virus (HSV) and is a common cause of corneal
blindness. Following a primary ocular herpetic
infection, latency of the virus occurs, followed by subsequent recurrences of
herpetic keratitis. Such recurrences may lead to structural damage of the cornea. Recurrent
herpetic keratitis is a common indication for
corneal transplantation. Recurrences of
herpetic keratitis in the corneal graft may lead to corneal graft rejection. Several
antiviral agents for HSV are available, including the
thymidine analogs. Prolonged use of
thymidine analogs may lead to toxicity of the ocular surface, including epithelial
keratitis, corneal
ulcers, follicular
conjunctivitis, and punctal occlusions. Availability of topical
antiviral agents that are safe and effective in the treatment and prophylaxis of
herpetic keratitis is highly desirable.
Ganciclovir is a potent inhibitor of members of the herpes virus family. The
drug has been used systemically for the treatment of cytomegalovirus (CMV)
retinitis. Its hematologic toxicity secondary to systemic administration led to its limited use in herpetic
infections. On the other hand, topical
ganciclovir has been shown to be as safe and effective as
acyclovir in the treatment of herpetic epithelial
keratitis. Furthermore, topical
ganciclovir can reach therapeutic levels in the cornea and aqueous humor following topical application. Several clinical trials have shown that topical
ganciclovir 0.15% ophthalmic gel is safe and effective in the treatment and prophylaxis of herpetic epithelial disease. Long-term use of
ganciclovir ophthalmic gel in patients with
penetrating keratoplasty following
herpetic keratitis has prevented recurrences of the disease. Topical
ganciclovir ophthalmic gel is well tolerated, does not cause toxic effects on the ocular surface, and does not cause hematologic abnormalities. Clinical studies have underscored the potential role of
ganciclovir ophthalmic gel in the treatment and prophylaxis of herpetic epithelial
keratitis. Future randomized, controlled, multicenter, prospective clinical trials are needed to assess the long-term safety and efficacy of topical
ganciclovir in the treatment and prevention of
herpetic keratitis and
uveitis.