Patient Friendly | Ocular Herpes Simplex vs. Herpes Zoster: What’s the Difference?

When people hear the word “herpes,” they often think of cold sores or shingles. But herpes viruses can also affect the eyes, sometimes leading to serious inflammation, pain, light sensitivity, corneal damage, or even vision loss if not treated quickly.

Two of the most important herpes-related eye conditions are ocular herpes simplex and herpes zoster ophthalmicus, also known as shingles around the eye. While they can sound similar, they are caused by different viruses, often look different, and may require different treatment plans.

At OPT-ISM, we evaluate red, painful, irritated, or light-sensitive eyes to help determine whether symptoms are due to a routine infection, inflammation, dry eye, contact lens complication, or a more serious viral eye disease.

Eye clinic scene: doctor points to herpes simplex keratitis eye photo as patient sits at slit lamp; HSV eye infection poster nearby.

What Is Ocular Herpes Simplex?

Ocular herpes simplex is most commonly caused by herpes simplex virus type 1, the same virus often associated with cold sores. When it affects the eye, it can cause a condition called herpes simplex keratitis, which means inflammation or infection of the cornea.

The cornea is the clear front window of the eye. Because the cornea plays a major role in focusing vision, inflammation or scarring in this area can cause blurred vision, discomfort, and long-term visual problems.

Herpes simplex eye disease can affect different layers of the cornea. A superficial infection may involve the outer epithelial layer, while deeper inflammation can involve the corneal stroma and may require more careful treatment. The American Academy of Ophthalmology notes that HSV epithelial keratitis requires antiviral treatment, while stromal keratitis often requires antiviral therapy along with anti-inflammatory treatment under close supervision.

Common Symptoms of Ocular Herpes Simplex

Ocular herpes simplex may cause:

• Eye redness

• Eye pain or irritation

• Watery eyes

• Light sensitivity

• Blurred vision

• Foreign body sensation

• Recurrent episodes in the same eye

• A history of cold sores, although not everyone has one

One classic finding eye doctors look for is a dendritic corneal lesion, which is a branching pattern on the cornea seen with special dye during an eye exam. This is one reason a proper slit lamp exam is so important when herpes simplex is suspected.

What Is Herpes Zoster Ophthalmicus?

Herpes zoster ophthalmicus, often shortened to HZO, is shingles involving the eye or the area around the eye. It is caused by the varicella-zoster virus, the same virus that causes chickenpox.

After a person has chickenpox, the virus can remain dormant in the nerves for years. Later in life, it can reactivate as shingles. When shingles affects the forehead, eyelid, scalp, or eye area, it may involve the ophthalmic branch of the trigeminal nerve and can become an eye emergency.

The CDC describes shingles as a painful rash illness caused by varicella-zoster virus, and shingles near the eye can lead to significant eye-related complications.

Common Symptoms of Herpes Zoster Around the Eye

Herpes zoster ophthalmicus may cause:

• Pain, burning, tingling, or sensitivity on one side of the forehead or scalp

• A blistering rash on one side of the face

• Eyelid swelling

• Red eye

• Eye pain

• Light sensitivity

• Blurred vision

• Headache or facial tenderness

• Inflammation inside the eye

A key difference from herpes simplex is that shingles often causes a painful skin rash in a nerve-like pattern, usually on only one side of the face. Sometimes eye symptoms can develop before, during, or after the rash.

Herpes Simplex vs. Herpes Zoster: Key Differences

Feature	Ocular Herpes Simplex	Herpes Zoster Ophthalmicus
Virus	Herpes simplex virus, usually HSV-1	Varicella-zoster virus
Common association	Cold sores, recurrent corneal infection	Shingles, prior chickenpox
Typical pattern	Often affects the cornea	Often affects forehead, eyelid, skin, and eye
Rash	Usually no shingles-type rash	Painful blistering rash, usually one-sided
Recurrence	Can recur multiple times	Can recur, but often presents as a shingles episode
Eye risk	Corneal ulcers, scarring, stromal inflammation	Keratitis, uveitis, glaucoma, retinal inflammation, nerve pain
Treatment	Antiviral eye drops, oral antivirals, sometimes steroid drops under supervision	Oral antivirals, pain control, and eye-specific treatment if the eye is involved

Why These Conditions Need Prompt Treatment

Both herpes simplex and herpes zoster can damage the eye if they are not treated appropriately.

With herpes simplex, the virus may affect the cornea and cause recurrent inflammation, corneal scarring, irregular astigmatism, or reduced vision. Steroid eye drops may be helpful in certain deeper inflammatory cases, but they can make some active infections worse if used incorrectly. That is why patients should not use leftover steroid drops for a red eye without being examined.

With herpes zoster ophthalmicus, inflammation may involve the cornea, the inside of the eye, the eye pressure system, the retina, or the optic nerve. HZO treatment commonly involves systemic antiviral medication and may also require topical steroids, dilating drops, pain control, or other medications depending on the structures involved.

How Eye Doctors Diagnose the Difference

An eye doctor will look closely at:

• The pattern of redness

• Whether the cornea has staining or ulceration

• Whether there are dendrites or pseudodendrites

• Eye pressure

• Inflammation inside the eye

• Eyelid or skin rash

• Pupil reaction

• Vision changes

• Contact lens history

• Immune system history

• Prior episodes

Special dye may be placed in the eye to highlight corneal defects. The eye is then examined with a slit lamp microscope to determine whether the problem is on the surface, in the cornea, or inside the eye.

Treatment for Ocular Herpes Simplex

Treatment depends on which part of the eye is affected.

For herpes simplex keratitis, treatment may include:

• Antiviral eye drops or ointment

• Oral antiviral medication

• Lubricating drops

• Careful follow-up exams

• Steroid eye drops only in specific cases and only under medical supervision

Mild herpes simplex eye disease is commonly treated with topical or oral antiviral medication. More serious or recurrent cases may require longer monitoring because corneal inflammation can return.

Treatment for Herpes Zoster Ophthalmicus

When shingles involves the eye area, early treatment is important. Treatment may include:

• Oral antiviral medication

• Lubricating drops

• Pain control

• Anti-inflammatory eye drops if the eye is inflamed

• Dilating drops if there is inflammation inside the eye

• Eye pressure treatment if glaucoma-like pressure elevation occurs

• Follow-up visits to monitor for delayed complications

Antiviral medication is most effective when started early, especially within the first few days of the rash. Wills Eye Hospital notes that shingles around the eye is treated with antiviral pills when caught in the first few days, and HZO can affect the eyeball with inflammation and glaucoma.

Can the Shingles Vaccine Help?

The shingles vaccine does not prevent herpes simplex eye disease, but it can help reduce the risk of shingles and shingles-related complications.

The CDC recommends two doses of recombinant zoster vaccine, Shingrix, for adults age 50 and older. It is also recommended for adults age 19 and older who are or will be immunocompromised because of disease or therapy.

Patients with a history of herpes zoster ophthalmicus should discuss vaccination timing with their primary care doctor, ophthalmologist, or optometrist, especially if they have had recent eye inflammation.

When to Call an Eye Doctor Right Away

You should schedule an urgent eye exam if you have:

• A painful red eye

• New light sensitivity

• Blurred vision

• A blistering rash near the eye

• Eyelid swelling with eye pain

• A history of herpes eye disease and new symptoms

• New corneal pain while wearing contact lenses

• One-sided forehead or scalp pain with eye irritation

• A red eye that is not improving

Do not assume every red eye is pink eye. Viral herpes-related eye disease can look like other conditions early on, but the treatment approach may be very different.

Can You Wear Contact Lenses With Ocular Herpes or Shingles?

In most cases, patients should stop wearing contact lenses until they are examined and cleared by their eye doctor.

Contact lenses can worsen irritation, increase infection risk, and make it harder for the cornea to heal. If you have eye pain, redness, light sensitivity, or blurred vision, remove your contacts and schedule an eye exam.

Final Thoughts

Ocular herpes simplex and herpes zoster ophthalmicus are both caused by herpes-family viruses, but they are not the same condition. Herpes simplex more commonly affects the cornea and may recur over time, while herpes zoster is shingles involving the nerves around the eye and may cause a painful rash, eyelid swelling, inflammation, and serious eye complications.

The most important takeaway is simple: a painful, red, light-sensitive eye should be evaluated promptly. Early diagnosis and treatment can help reduce the risk of scarring, prolonged inflammation, and vision loss.

At OPT-ISM, we evaluate red eyes, painful eyes, light sensitivity, and suspected eye infections to help patients get the right diagnosis and treatment plan.