Eye Herpes: Symptoms, Causes, and Treatment Options Explained

Know what eye herpes means

Herpes simplex eye infection is an infection of the cornea caused by herpes simplex virus, or HSV. The cornea is the clear dome over the colored part of your eye. When HSV infects the cornea, the condition is called herpes simplex keratitis.

Ocular herpes can affect more than the cornea. Depending on the virus and the pattern of disease, it may involve the eyelids, conjunctiva, cornea, iris, or retina. The conjunctiva is the thin membrane covering the white of your eye and lining your eyelids. Herpes-related eye disease can be caused by herpes simplex virus types 1 and 2. Retinal disease can occur but is uncommon. The term ocular herpes therefore covers several clinical patterns rather than one uniform illness.

Herpes-related eye disease can resemble pink eye, especially when it causes a red, irritated eye. Adenovirus pink eye was described as almost always affecting both eyes, while herpes simplex conjunctivitis was described as almost always affecting one eye. In a 2013 American Academy of Ophthalmology article, an expert estimated that about 25 percent of people with conjunctivitis in one eye had herpes.

A 2013 ophthalmology article reported about 50,000 new and recurring ocular HSV cases diagnosed each year in the United States. That figure measures diagnosed new and recurring cases, not your personal likelihood of having this infection. A red eye alone cannot identify the cause.

Understand how it starts and returns

Most herpes simplex eye infections come from HSV-1. HSV-2 can also cause keratitis, but it is less common. The virus spreads through direct contact with infected skin lesions or secretions.

Touching an active cold sore and then touching your eye can transfer HSV to the eye. If you have an active cold sore or blister, avoid touching your eyes. This reduces the chance of transferring virus from the infected lesion to the eye.

After the first infection, HSV can remain dormant in nerve roots. It may later reactivate and cause another episode in or around the eye. Reactivation does not mean that you caused the infection again; it reflects the virus becoming active after its dormant phase.

Risk factors include:

• UV-A exposure
• A weakened immune system
• Trauma to the ocular surface
• Some topical medicines
• Atopic dermatitis

Having one of these factors does not establish a diagnosis. It gives an eye clinician useful context when reviewing your symptoms and history. Other recognized reactivation triggers include fever, significant physical stress, and steroid medicine use. UV exposure can include intense sunlight or some procedures that use ultraviolet light. These details can help an eye clinician interpret symptoms that appear after a trigger, but none of them establishes that HSV is active.

The two figures measure new cases and reactivations separately. Published estimates may count new cases and recurrences differently. Most HSV epithelial keratitis resolves on its own within three weeks, but treatment aims to reduce deeper corneal damage and scarring.

Notice the pattern in one eye

Herpes simplex eye infections usually affect one eye. That one-sided pattern can help an eye clinician think about possible herpes, but it does not prove that herpes is the cause.

Herpes-related eye symptoms can include:

• Eye pain or a gritty, foreign-body feeling
• Redness and watering or tearing
• Sensitivity to light
• Blurred vision or another change in eyesight
• A swollen eyelid
• Blisters or a rash on the eyelid or nearby skin

You may have only some of these signs. The severity and combination can change depending on which eye structure is involved.

Herpes-related conjunctivitis can look like ordinary conjunctivitis, commonly called pink eye. Follicular conjunctivitis may be mistaken for another form of conjunctivitis, and eyelid blisters may not appear. A red eye affecting one eye, especially with pain, light sensitivity, or blurred vision, deserves an eye-care assessment rather than a diagnosis based on appearance alone.

Match symptoms to the affected eye structure

The first HSV eye infection is usually a nonspecific, self-limiting conjunctivitis. If the cornea is involved, symptoms can include a foreign-body sensation, tearing, light sensitivity and redness. Eyelid blisters may follow, and vision can become blurred.

The cornea has several layers, and the pattern of involvement matters:

• Epithelial keratitis affects the outer corneal layer. It often creates a branching, tree-like lesion called a dendritic ulcer. A dendrite is the typical pattern of HSV infection on the corneal surface.
• Geographic keratitis is a less common, larger ulcerative form of infection on the corneal surface.
• Stromal keratitis affects deeper corneal tissue. It carries a greater risk of scarring and lasting vision changes.
• Endotheliitis, also called disciform keratitis, affects the deepest corneal layer. It can cause swelling and clouding. HSV can also trigger inflammation inside the eye, called anterior uveitis. This inflammation may raise eye pressure, so the clinician may need to assess more than the corneal surface.

A clinical review reported that epithelial keratitis accounts for 70% to 80% of HSV keratitis cases. That percentage measures the share of HSV keratitis cases involving the corneal surface in the cited review. The remaining patterns can involve deeper tissue and may need a different treatment approach.

The difference between surface and deeper disease is more than a label. Epithelial disease usually involves actively replicating virus, while stromal disease usually involves an immune reaction after infection. Because the underlying process differs, an eye clinician must identify the affected layer before choosing treatment.

Know what happens during an eye evaluation

Clinicians usually diagnose HSV keratitis from your history and the findings seen during a slit-lamp examination. A slit lamp is a microscope with a focused beam of light that lets the clinician examine your cornea, eyelids, conjunctiva, and other visible eye structures closely. Tell the clinician when symptoms began, whether they affect one or both eyes, whether you have had a cold sore, and whether you have had a similar episode before.

A branching dendritic lesion is enough to confirm HSV dendritic keratitis in most cases. The clinician may use a dye to make the corneal surface pattern easier to see. The appearance of the lesion, its location, and the depth of involvement all affect the diagnosis and treatment plan.

Viral culture or a NAAT swab may help confirm HSV when the findings are not typical, but these tests are not readily available in most clinical settings. Culture and PCR detect live virus. They cannot diagnose or rule out stromal disease driven by an immune reaction after an earlier infection. A negative test therefore does not by itself rule out every form of herpes-related corneal disease. If another microbial cause is possible, bacterial and fungal cultures or a specialized imaging test called confocal microscopy may help investigate it. These options address a different diagnostic question than testing for live HSV. They may be considered when the lesion or course does not fit the usual HSV pattern.

Other infections can look like HSV. A clinical review described several studies in which lesions initially diagnosed as HSV were later identified as other infections: 8% were caused by varicella zoster virus, 5% by adenovirus, 3.2% by cytomegalovirus, and 2.7% by enterovirus. These figures measure the misidentified lesions in the cited studies, not the chance that your symptoms have one of those causes. This distinction matters when a lesion is atypical. One study found only moderate agreement between clinical and PCR assessments, while atypical lesions showed very little agreement. The clinician may therefore weigh the examination, history, and testing together. Amebic and fungal infections have also been mistaken for HSV keratitis, so appearance alone cannot identify the cause.

The examination and history remain central even when testing is considered. A test result must be interpreted alongside the corneal findings, the symptom pattern, and whether the suspected disease involves active virus or an immune response.

Expect treatment to follow the disease pattern

Treatment depends on which tissue is affected and whether active virus or immune-mediated disease is present. Epithelial disease usually involves active virus. Stromal disease usually involves an immune reaction. The treatments are different, so a medicine that is appropriate for one pattern may be unsuitable for another.

Epithelial herpes infection is treated with topical or oral antiviral medicine prescribed by a clinician. Depending on the clinical pattern, clinicians may use topical ganciclovir or trifluridine, or oral acyclovir, valacyclovir, or famciclovir. The choice depends on the examination and the clinician’s assessment, not only on whether your eye is red. These medicines target the virus itself.

HSV stromal keratitis typically requires antiviral therapy together with a topical corticosteroid prescribed and monitored by an eye clinician. The corticosteroid addresses the immune reaction, while antiviral treatment is used alongside it under clinical supervision. Do not start, stop, or change these medicines without the prescribing clinician’s direction.

Oral antiviral medicines require caution in people older than 65 years and in people with reduced kidney function. Tell the clinician about your age, kidney problems, allergies, and other medicines before treatment is selected. Those details can affect which medicine is appropriate and how it is monitored. Oral acyclovir performed at least as well as topical acyclovir ointment in two randomized trials, but it is not specifically FDA approved for HSV epithelial keratitis. That evidence supports one option; it does not make oral treatment right for every person.

Avoid treatment choices that can worsen the problem

An eye clinician may gently remove diseased surface cells in some cases. Evidence does not consistently show that removing those cells and then using an antiviral works better than antiviral treatment alone. This is a clinician-performed procedure, not a step to attempt yourself.

A 2015 Cochrane review found that topical trifluridine, acyclovir, or brivudine healed about 90% of treated eyes within two weeks in the reviewed evidence. The review found no significant difference in effectiveness among those treatments. The 90% figure measures treated eyes in the reviewed studies; it does not promise the same result for every person.

A 2007 Cochrane review included 98 trials involving 5,211 participants. It found that topical vidarabine, trifluridine, or acyclovir led to significantly more healing within one week than idoxuridine. The number 98 measures trials, and 5,211 measures participants included in that review. Those figures describe the review, not a personal treatment prediction.

Plan for healing and possible recurrence

A single episode of epithelial HSV keratitis treated promptly and appropriately often heals without lasting vision problems. Most HSV epithelial keratitis resolves on its own within three weeks, but treatment is used to reduce the chance of deeper corneal damage and scarring. Healing still needs clinical follow-up because the surface appearance and the underlying disease pattern can change.

Herpes simplex keratitis can recur. One patient-facing source reported that around half of people who get HSV keratitis will have another episode within five years. That figure measures the reported recurrence within five years in that source and does not predict whether your infection will return.

Repeated infections and stromal keratitis can cause corneal scarring that permanently blurs vision. Repeated inflammation may also cause corneal thinning, abnormal blood-vessel growth, and deeper corneal inflammation. Repeated nerve damage can reduce corneal sensation.

A clinical review reported that HSV stromal keratitis accounted for 2% of initial HSV-1 eye presentations but caused 20% to 61% of recurrent disease. The first figure measures initial eye presentations, while the second measures recurrent disease in the cited review. These figures help explain why recurrence deserves follow-up even when an earlier episode improved.

If infections keep returning, your doctor might recommend a daily oral antiviral to help prevent future infections. The decision depends on your recurrence pattern, examination findings, medical history, and the clinician’s assessment. Take preventive medicine only as prescribed.

Arrange an eye exam for these warning signs

Arrange prompt eye-care evaluation if you have a painful or red eye affecting one side, watering, light sensitivity, blurred or changing vision, eyelid blisters, or a rash around the eye. These signs can have several causes, but herpes-related eye disease is one possibility that needs an examination rather than guesswork.

If symptoms of ocular herpes return, see an ophthalmologist immediately. Have each recurrence checked by an eye doctor as soon as possible. Do not wait for a familiar pattern to become severe before arranging care.

Untreated or severe eye herpes can cause corneal scarring, vision loss, or blindness. Seek immediate qualified eye care for severe or worsening symptoms.

Book the next eye-care step

Concerning or recurring symptoms deserve an eye-care evaluation because the cornea and deeper eye tissues may need different treatment. Bring these details to the visit:

• When the symptoms began and whether they are getting worse
• Which eye is affected
• Any earlier episodes or cold sores
• Possible contact with an active blister
• Your current medicines and relevant health conditions

A qualified eye-care professional decides which evaluation and treatment fit your findings.

What should I do if I think I have eye herpes?

Is eye herpes always an infection of the cornea?

No. Eye herpes can involve the eyelids, conjunctiva, cornea, iris, or retina. Herpes simplex keratitis specifically means infection of the cornea. Because treatment depends on the affected tissue and whether active virus or an immune reaction is present, an eye examination is needed before choosing treatment.

Can a negative test rule out eye herpes?

No. Culture or PCR may help confirm herpes when the eye findings are unusual, but these tests detect live virus. They cannot rule out stromal disease caused by an immune reaction after an earlier infection. Clinicians interpret test results with your history and slit-lamp examination findings.

When might a daily antiviral be used for recurring eye herpes?

A clinician might recommend a daily oral antiviral when eye herpes keeps returning. The decision depends on your recurrence pattern, examination findings, medical history, and other medicines. Take preventive treatment only as prescribed, and have each new episode evaluated promptly because repeated inflammation can scar the cornea.

Can eye herpes spread from a cold sore to the eye?

Yes. Touching an active cold sore or blister and then touching your eye can transfer herpes simplex virus. Avoid touching your eyes when a sore is present, and do not rub an irritated eye after contact. Suspected symptoms still need an eye-care examination because several conditions can look similar.