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The AOA’s CLCS Newsletter, November 2014
Managing ocular herpes simplex virus with oral antivirals
Chris Smiley, O.D.
A contact lens and cornea practice will encounter a handful of conditions
requiring oral medications. The following summarizes the role of oral antiviral
treatments for the management of herpes simplex virus (HSV), in the contact
lens practice.
Herpes Simplex Virus (HSV) Epithelial Keratitis
The mainstay treatment for epithelial HSV keratitis is a topical anti-viral medication, including
Zirgan® (gangciclovir 15 percent gel) or Viroptic (trifluridine 1 percent solution).
There are some reports of HSV epithelial keratitis cases being treated effectively with oral
mono-therapy.1 Due to the lack of large scale clinical trials, such use remains controversial. It
is common practice to use oral antivirals as an adjunct to topical treatment. These medications
are not indicated by the FDA for this use. Therefore, prescribing oral antivirals for HSV
epithelial keratitis is an off label use of the medication.
Oral Antiviral Medications and Dosing for HSV Adjunctive Treatment
Zovirax
(acyclovir)
400mg five times per day for seven to 10 days
Valtrex
(valacyclovir)
500mg three times per day for seven to 10 days
Famvir
(famciclovir)
250mg three times per day for seven to 10 days
Herpes Simplex Stromal Keratitis
Stromal HSV has the biggest risk for causing permanent corneal scarring and vision loss.
Twenty to 30 percent of patients with an epithelial HSV lesion develop an immune stromal
reaction within five years of the initial episode.2 The treatment of choice for the immune stromal
response is a topical corticosteroid, including Durezol or Pred Forte. It is important to stress
that in contrast to HSV stromal keratitis, corticosteroid drops are generally contraindicated in
active epithelial HSV. Therefore, ruling out any corneal involvement, or dendritic sign to assure
there is only stromal involvement is essential prior to initiating corticosteroid therapy.
The National Eye Institute Herpetic Eye Disease Study (HEDS I) showed no benefit to adding
oral acyclovir when patients were already taking topical corticosteroids and topical antivirals in
HSV stromal keratitis.3,4 Practitioners frequently add topical antivirals and on occasion oral
antivirals as an adjunctive therapy, particularly when an epithelial lesion is also present.
Oral Antivirals for Prophylaxis
In the National Eye Institute Herpetic Eye Disease Study (HEDS II), found that taking 400mg
acyclovir BID for 12 months reduced the probability that any form of herpes simplex of the eye
would return, if an infection existed in a prior year. More importantly there was a 50 percent
reduction in the rate of return of herpes stromal keratitis.5,6 Some clinicians use 500mg or
1000mg Valtrex once daily for prophylactic therapy. Oral antiviral medications play a critical role
in prophylactic HSV therapy, especially in cases where recurrence is an issue.
The AOA’s CLCS Newsletter, November 2014
Herpes Simplex and Contact Lenses
Three studies looked at the role of contact lenses in the recurrence of HSV keratitis. Two of
those studies, including the HEDS study, determined that there is no association with HSV
keratitis recurrence and contact lenses.7,8 One cohort study did show contact lenses increased
the likelihood of HSV keratitis reoccurrence.9 The study had some limitations and was unable to
control for antiviral prophylaxis in both groups. The contact lens wearing group of patients at
the Cleveland Clinic likely suffered from more severe prior eye disease, and therefore the
probability of reoccurrence was naturally higher. So there is conflicting data on the impact of
contact lenses in HSV recurrence. Patient counseling and closer monitoring of recurrent cases
is indicated.
References:
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8.
9.
Collum LM, McGettrick P, Akhtar J, et al. Oral acyclovir (Zovirax) in herpes simplex dendritic corneal ulceration. Br J
Ophthalmol. 1986 Jun;70(6):435-8.
Knickelbein JE, Hendricks RL, Charukamnoetkanok P. Management of herpes simplex virus stromal keratitis: An
evidence-based review. Surv Ophthalmol 2009;54(2):226-34.
The Herpetic Eye Disease Study Group. A controlled trial of oral acyclovir for the prevention of stromal keratitis or iritis
in patients with herpes simplex virus epithelial keratitis. Arch Ophthalmol. 1997 Jun;115(6):703-12.
https://www.nei.nih.gov/neitrials/static/study37.asp Webpage accessed October 2014
https://www.nei.nih.gov/neitrials/static/study38.asp Webpage accessed October 2014
Young RC, Hodge DO, Liesegang TJ, Baratz KH. Incidence, recurrence and outcomes of herpes simplex virus eye
disease in Olmsted County, MN. 1976-2007: The effect of oral antiviral prophylaxis. Arch Ophthalmol. 2010
Sep;128(9):1178-83.
HEDS. Psychological stress and other potential triggers for recurrences of herpes simplex virus eye infections.
Herpetic Eye Disease Study Group. Arch Ophthalmol. 2000 Dec;118(12):1617-25.
Brandt BM, Mandleblatt J, Asbell PA. Risk factors for herpes simplex-induced keratitis: a case-control study. Ann
Ophthalmol. 1994 Jan-Feb;26(1):12-6.
Mucci JJ, Utz VM, Galor A, Feuer W, Jeng BH. Recurrence rates of herpes simplex virus keratitis in contact lens and
non-contact lens wearers. Eye Contact Lens. 2009 Jul;35(4):185-7. doi: 10.1097/ICL.0b013e3181a9d788.
Dr. Smiley is the owner of Vision Professionals, a two-location private practice in Columbus,
Ohio. He was a 2001 recipient of the American Optometric Foundation Award of Excellence in
Patient Contact Lens Care. He has served as a clinical investigator for various contact lens
manufacturers. Dr. Smiley is a Clinical Assistant Professor of Optometry at The Ohio State
University College of Optometry. Dr. Smiley can be reached for comment at
[email protected]
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