What Is Herpes Simplex Keratitis?
Herpes simplex keratitis is a corneal infection caused by herpes simplex virus type 1 (HSV-1) — the same virus responsible for cold sores around the mouth. After a primary infection in childhood, the virus lies dormant in the trigeminal nerve and can reactivate at any point in life, traveling along the nerve to the cornea. The most recognizable form is the “dendritic ulcer” — a branching, tree-like pattern on the corneal surface visible with fluorescein staining under a slit lamp.
HSV keratitis is typically unilateral (one eye), painful, and accompanied by light sensitivity and decreased vision. Repeated episodes can scar the cornea over time, which is why early diagnosis and prompt antiviral therapy are essential. For patients with frequent recurrences, daily oral antiviral suppression has been shown in landmark trials to reduce recurrence by about half.
Critical warning: if you have had cold sores and develop a painful red eye, do not use any leftover steroid eye drops. Topical steroids without antiviral coverage can dramatically worsen herpes keratitis. Get evaluated first.
Symptoms
Signs of HSV Keratitis
Severe Pain or Discomfort
Often more painful than typical pink eye, with a deep aching or burning sensation in one eye.
Marked Light Sensitivity
Bright lights become difficult to tolerate due to inflammation of the cornea and inside of the eye.
Blurred Vision
Decreased vision in the affected eye, sometimes dramatic if the dendritic lesion is in the central cornea.
Unilateral Redness
Almost always affects only one eye, unlike viral or bacterial conjunctivitis which often spread to both.
History of Cold Sores
Many patients have a history of oral herpes outbreaks, recent stress, illness, or sun exposure.
Decreased Corneal Sensation
A subtle but important clinical sign — the cornea may feel less sensitive than the unaffected eye.
Why Choose PersonalEyes for HSV Keratitis Care
Diplomate Expertise
Dr. Patel is a Diplomate of the American Board of Optometry with deep experience in corneal disease and antiviral management.
Long-Term Care
We follow HSV patients longitudinally to monitor for recurrence, manage suppression therapy, and adjust treatment as needed.
Coordinated Referrals
For severe stromal disease or vision-threatening complications, we coordinate seamlessly with corneal specialists.
Frequently Asked Questions
