Conditions We Treat
Ocular Herpes (HSV Keratitis)
Ocular herpes is an eye infection caused by the herpes simplex virus (HSV) — the same family of virus responsible for cold sores. After the first exposure, the virus lies dormant in the nerves and can reactivate on the eye, usually affecting the cornea (herpes simplex keratitis). It is one of the most common infectious causes of corneal scarring and vision loss, and it tends to recur, typically in the same eye.
The classic finding: a dendritic ulcer
The signature of ocular HSV is a dendritic ulcer — a branching, tree-like sore on the surface of the cornea, which we can see under the microscope with a special stain. The virus can also cause deeper inflammation within the cornea (stromal keratitis) and inflammation inside the eye (uveitis). Repeated episodes can reduce the cornea's sensation and clarity over time.
Symptoms and triggers
- Eye pain, redness, and tearing
- Light sensitivity and blurred vision
- A foreign-body or scratchy sensation
- Symptoms that recur, often in the same eye
Reactivation can be triggered by stress, illness or fever, sunlight (UV exposure), and other infections.
How we treat ocular herpes
- Antiviral therapy is the foundation — a topical antiviral (such as ganciclovir gel) and/or oral antivirals (acyclovir or valacyclovir). For surface (dendritic) disease, the infected epithelium may also be gently debrided.
- Careful use of steroids — anti-inflammatory steroid drops help deeper stromal inflammation, but they are used only with antiviral coverage and close supervision. This is important: steroid drops used alone on a dendritic ulcer can make the infection dramatically worse, which is why a red eye should never be self-treated with leftover steroid drops.
- Long-term prevention — for patients with frequent recurrences or stromal disease, a daily oral antiviral can significantly reduce the number of future episodes and protect the cornea.
- Monitoring for complications such as scarring, reduced corneal sensation, and elevated eye pressure; advanced scarring may eventually require a corneal transplant.
If you have a red, painful, light-sensitive eye — especially one that has acted up before — prompt evaluation lets us start antivirals quickly and protect your vision.
This page is for general education and is not medical advice. If you have symptoms or concerns, please request an appointment for an evaluation.