Herpes Simplex Epithelial Keratitis (HSEK) is an eye infection affecting the thin, clear front layer of the eye called the corneal epithelium. It is caused by the herpes simplex virus (HSV), most often HSV type 1. The virus invades and kills surface cells, creating branching “dendritic” ulcers that stain with special dyes during examination. These ulcers can cause pain, light sensitivity, redness, and blurred vision. If left untreated, HSEK can lead to scarring, loss of corneal sensation, and even permanent vision loss Wikipedia.
Herpes Simplex Epithelial Keratitis is an infection of the outer layer of the cornea caused by the herpes simplex virus (HSV). It shows up as painful sores on the clear front surface of the eye called the corneal epithelium. When the virus that hides in the nerve cells around the eye wakes up, it travels down the nerves to the cornea and causes these sores. This condition is common worldwide and can lead to vision problems if not treated in time. It most often affects one eye at a time and may come back again and again over months or years. (en.wikipedia.org)
The corneal epithelium is the thin, clear sheet of cells covering the front of the eye. In epithelial keratitis, these cells become damaged or die, leaving ulcers and rough patches. These injuries cause pain, light sensitivity, and blurred vision. Although the human body can fight many infections on its own, HSV can hide in nerve cells for life, making herpes keratitis a long-term problem for some people. Early treatment with antiviral medicines can help heal the infection faster and reduce the risk of scarring. (ncbi.nlm.nih.gov, uspharmacist.com)
Types of HSV Epithelial Keratitis
HSV epithelial keratitis can appear in several forms depending on how the virus damages the epithelium:
- Dendritic Keratitis — The classic form shows branching, tree-like ulcers made of dying cells. These dendritic ulcers stain with special dyes so doctors can see their shape under a microscope. (en.wikipedia.org)
- Geographic Keratitis — When a dendritic ulcer grows larger and the edges break down, it becomes a geographic ulcer. The shape then looks like a map—hence the name. Without quick treatment, these ulcers can cover large parts of the cornea. (en.wikipedia.org)
- Metaherpetic Ulcer — Here, the virus itself is no longer active, but the cornea cannot heal properly, leading to persistent defects. The surface remains raw and slow to close even when antivirals clear the virus. (en.wikipedia.org)
- Necrotizing Keratitis — A rare but severe form where active virus and immune reactions destroy large areas of the cornea tissue. It can quickly lead to thinning (melting) and risk of perforation. (en.wikipedia.org)
- Keratouveitis — When the infection spreads inward, it can cause inflammation of both the cornea and the layer behind it called the uvea. This form shows corneal damage plus signs of deeper inflammation like cells floating in the fluid inside the eye. (en.wikipedia.org)
Causes of HSV Epithelial Keratitis
- Reactivation of Latent HSV — After a first infection, HSV hides in nerve cells near the eye. If the virus reactivates, it travels back to the cornea and causes new ulcers. (en.wikipedia.org)
- Physical Stress — Illness, fever, or surgery can weaken the immune system and trigger the virus to wake up. (cdc.gov)
- Emotional Stress — Strong stress or anxiety can alter immune responses, making it easier for HSV to reactivate. (cdc.gov)
- Ultraviolet Light Exposure — Sunlight and tanning beds can damage corneal cells and help the virus reactivate. (cdc.gov)
- Hormonal Changes — Fluctuations during menstrual cycles or pregnancy can affect immunity and HSV control. (cdc.gov)
- Contact Lens Wear — Overwearing or poor hygiene can scratch the cornea and open a door for the virus. (mayoclinic.org)
- Eye Trauma — Any scratch or injury to the eye surface may trigger latent HSV in nearby nerves. (mayoclinic.org)
- Immunosuppression — Diseases like HIV or drugs that lower immunity (steroids, chemotherapy) allow HSV to reactivate more easily. (cdc.gov)
- Cold Sores — An active herpes labialis outbreak on the lips often precedes or accompanies eye reactivation. (en.wikipedia.org)
- Malnutrition — Lack of essential vitamins and minerals weakens defenses against viral infections. (mayoclinic.org)
- Dehydration — Dry eye and reduced tear flow make it harder for the eye to clear viruses and heal. (mayoclinic.org)
- Fever — High body temperature signals inflammation, which can help HSV break its latency. (cdc.gov)
- Allergic Eye Disease — Ongoing inflammation from allergies can disrupt the corneal barrier, inviting HSV. (mayoclinic.org)
- Chronic Sinusitis — Nearby infections and inflammation share immune signals that may wake up HSV in the face. (eyewiki.org)
- Dental Procedures — Manipulation near the trigeminal nerves, like tooth extraction, can trigger viral travel to the eye. (cdc.gov)
- Ocular Surgery — Operations on the eye or around it can disturb nerves and immune balance, leading to HSV flare-ups. (cdc.gov)
- Radiation Exposure — Treatments near the head or neck may damage tissues and reactivate HSV. (cdc.gov)
- Chemotherapy — Cancer drugs lower white blood cells, cutting defenses against latent viruses. (cdc.gov)
- Chronic Illness — Long-term diseases like diabetes can impair immunity and wound healing. (mayoclinic.org)
- Aging — As people get older, immune surveillance weakens, making viral reactivation more likely. (en.wikipedia.org)
Symptoms of HSV Epithelial Keratitis
- Eye Pain — Often sharp and intense, pain comes from epithelial ulcers irritating nerve endings. (ncbi.nlm.nih.gov)
- Redness — Blood vessels in the white part of the eye widen, making it look pink or red. (ncbi.nlm.nih.gov)
- Light Sensitivity — The eye hurts more in bright places because damaged cells expose nerves. (ncbi.nlm.nih.gov)
- Tearing (Lacrimation) — The eye produces extra tears to flush out irritants and help healing. (ncbi.nlm.nih.gov)
- Blurred Vision — Surface irregularities and ulcers scatter light, making images fuzzy. (ncbi.nlm.nih.gov)
- Foreign Body Sensation — Patients feel like something is stuck in the eye, from rough patches on the cornea. (ncbi.nlm.nih.gov)
- Itching — Mild itching may occur, though pain and burning are more common. (ncbi.nlm.nih.gov)
- Discharge — A watery or slightly sticky fluid can come out, carrying away dead cells. (uspharmacist.com)
- Swelling of Eyelids — Sometimes the lids puff up from nearby inflammation. (ncbi.nlm.nih.gov)
- Headache — Intense eye pain can spread as a headache around the eyebrow or temple. (ncbi.nlm.nih.gov)
- Decreased Corneal Sensitivity — Over time, repeated damage can numb the cornea. (en.wikipedia.org)
- Photophobia — Extreme discomfort in normal light, often forcing patients to close the eye. (ncbi.nlm.nih.gov)
- Eye Fatigue — Ongoing irritation makes keeping the eye open tiring. (ncbi.nlm.nih.gov)
- Twitching — Strong blinking or squinting to protect the painful eye can cause muscle spasms. (ncbi.nlm.nih.gov)
- Tissue Staining — When doctors put a dye on the eye, damaged spots light up under blue light. (uspharmacist.com)
Diagnostic Tests
Physical Exam
- Slit Lamp Examination — A special microscope shines a thin beam of light into the eye. Dendritic ulcers show up clearly when the doctor adds fluorescein dye. (uspharmacist.com)
- Visual Acuity Test — Charts with letters help measure how well the patient can see at different distances. Blurred vision hints at surface damage. (mayoclinic.org)
- Pupillary Light Reflex — Shining a light into the eye checks nerve and muscle reactions; slow or uneven response may mean deeper inflammation. (mayoclinic.org)
- External Inspection — Looking at the eyelids and whites of the eye for redness, swelling, or sores adds clues to the diagnosis. (mayoclinic.org)
Manual Tests
- Cochet-Bonnet Esthesiometry — A thin nylon filament touches the cornea to measure sensitivity. Less sensation can indicate nerve damage from HSV. (en.wikipedia.org)
- Tzanck Smear — A small scraping from the ulcer is stained on a slide. Giant cells suggest HSV but the test is less accurate. (pmc.ncbi.nlm.nih.gov)
- Impression Cytology — A clear strip of paper gently lifts superficial cells. Lab analysis can show viral changes in those cells. (pmc.ncbi.nlm.nih.gov)
- Corneal Scrapings for Culture — Scraping cells from the ulcer and growing them in a lab can confirm live virus but takes days. (pmc.ncbi.nlm.nih.gov)
Laboratory & Pathological Tests
- Polymerase Chain Reaction (PCR) — PCR quickly finds HSV genetic material in tiny samples. It is very sensitive and specific. (reviewofophthalmology.com)
- Viral Culture — Placing scrapings in special media can grow HSV, which confirms active infection but is slower. (pmc.ncbi.nlm.nih.gov)
- Direct Fluorescent Antibody (DFA) Test — Fluorescent tags stick to viral proteins in samples, lighting up under a special microscope. (pmc.ncbi.nlm.nih.gov)
- Enzyme-Linked Immunosorbent Assay (ELISA) — Blood or tear samples are tested for antibodies or viral antigens using color-changing reactions. (pmc.ncbi.nlm.nih.gov)
Electrodiagnostic Tests
- Blink Reflex Test — Gentle electrical pulses near the eye measure nerve wiring; HSV can slow signal speed. (pmc.ncbi.nlm.nih.gov)
- Corneal Nerve Conduction — Emerging tests measure electrical signals in corneal nerves to detect damage from repeated infection. (pmc.ncbi.nlm.nih.gov)
- Electrophoretic Tear Analysis — Lab machines separate tear proteins by electrical charge; unusual patterns can suggest active HSV. (pmc.ncbi.nlm.nih.gov)
- Electroretinogram (ERG) — Although more for retina, ERG may be checked if deeper layers are inflamed to rule out linked problems. (mayoclinic.org)
Imaging Tests
- Anterior Segment Optical Coherence Tomography (AS-OCT) — A non-contact scan creates detailed images of corneal layers, showing ulcer depth. (mayoclinic.org)
- In Vivo Confocal Microscopy — High-magnification imaging lets doctors see viral particles and cell damage directly in the living cornea. (mayoclinic.org)
- Fluorescein Angiography — Dye injected in the arm shows blood flow in eye vessels, useful if deeper inflammation is suspected. (mayoclinic.org)
- Ultrasound Biomicroscopy — High-frequency sound waves scan the front eye structures; helpful when scarring or opacity blocks light. (mayoclinic.org)
Non-Pharmacological Treatments
Warm Compress
Description: A clean cloth soaked in warm water and applied gently over closed eyelids for 5–10 minutes.
Purpose: Relieves discomfort and promotes blood flow.
Mechanism: Heat dilates small vessels, enhancing immune cell delivery to the cornea.
Cool Compress
Description: A chilled, damp cloth placed on closed eyelids for 5 minutes.
Purpose: Reduces redness and soothes pain.
Mechanism: Cold causes blood vessel constriction, reducing inflammation.
Artificial Tears
Description: Over-the-counter preservative-free lubricating drops used hourly.
Purpose: Keeps the eye moist and rinses debris.
Mechanism: Forms a protective film over the cornea, aiding healing.
Eyelid Hygiene
Description: Cleaning eyelid margins with diluted baby shampoo or commercially available lid scrubs once daily.
Purpose: Removes discharge and bacteria that can worsen infection.
Mechanism: Reduces microbial load and prevents secondary infection.
Moisture-Chamber Spectacles
Description: Wraparound glasses creating a humid environment around the eyes.
Purpose: Maintains moisture on the corneal surface.
Mechanism: Prevents tear evaporation, promoting epithelial healing.
UV-Protective Sunglasses
Description: Dark glasses blocking UVA and UVB rays when outdoors.
Purpose: Shields healing cornea from harmful ultraviolet light.
Mechanism: UV blockage prevents additional cell damage and inflammation.
Screen Time Limitation
Description: Reducing digital device use to short intervals with frequent breaks.
Purpose: Minimizes eye strain and dryness.
Mechanism: Allows normal blinking and tear distribution to protect the ocular surface.
Proper Lighting
Description: Using soft, indirect light instead of harsh overhead or screen light.
Purpose: Reduces glare and light sensitivity.
Mechanism: Lower light intensity decreases corneal irritation.
Room Humidification
Description: Running a cool-mist humidifier to keep indoor air moist.
Purpose: Prevents tear evaporation overnight.
Mechanism: Higher ambient humidity supports tear film stability.
Avoid Dusty or Smoky Environments
Description: Steering clear of pollution, smoke, and dust exposure.
Purpose: Prevents additional irritation and infection risk.
Mechanism: Reduces particulate matter contact with the healing cornea.
Avoid Eye Rubbing
Description: Consciously preventing rubbing or touching the eyes.
Purpose: Stops mechanical damage and viral spread.
Mechanism: Prevents disruption of fragile epithelial cells.
Hand Hygiene
Description: Washing hands frequently with soap, especially before touching the face.
Purpose: Reduces transfer of virus to the eye.
Mechanism: Soap inactivates HSV on the skin.
Discontinue Contact Lens Wear
Description: Temporarily stopping lens use during active infection.
Purpose: Prevents mechanical trauma and secondary infection.
Mechanism: Eliminates foreign-body stress on the cornea.
Stress Management
Description: Practicing relaxation techniques, such as deep breathing or guided imagery.
Purpose: Lowers risk of viral reactivation.
Mechanism: Reducing stress hormones supports immune function.
Adequate Sleep
Description: Aiming for 7–9 hours of restful sleep each night.
Purpose: Supports overall immune health.
Mechanism: Growth hormone release and cellular repair occur during sleep.
Hydration
Description: Drinking at least 8 cups of water daily.
Purpose: Helps maintain tear production.
Mechanism: Proper fluid balance ensures a healthy tear film.
Steam Inhalation
Description: Inhaling warm steam for 5 minutes twice daily.
Purpose: Loosens mucus and supports tear gland function.
Mechanism: Moist heat stimulates tear secretion.
Breathing Exercises
Description: Performing slow, deep inhalations and exhalations for 5 minutes.
Purpose: Calms the nervous system.
Mechanism: Lowers cortisol to support immunity.
Mindfulness Meditation
Description: Meditating for 10 minutes daily using guided apps or silent focus.
Purpose: Reduces stress-triggered HSV outbreaks.
Mechanism: Alters brain pathways that control stress responses.
Omega-3 Rich Diet Support
Description: Eating fatty fish or taking fish oil capsules.
Purpose: Lowers ocular surface inflammation.
Mechanism: Omega-3 fatty acids modulate inflammatory mediators.
Evidence-Based Drug Treatments
Oral Acyclovir (Zovirax®)
Class: Nucleoside analogue
Dosage: 400 mg by mouth 5 times daily for 7–10 days
Time: Continue until ulcer healing, then 3 more days
Purpose: Stops viral DNA replication
Mechanism: Converted to acyclovir triphosphate, blocking viral DNA polymerase
Side Effects: Headache, nausea, rarely kidney issues AAONCBI
Oral Valacyclovir (Valtrex®)
Class: Pro-drug of acyclovir
Dosage: 500 mg by mouth twice daily for 7–10 days
Purpose: Improved absorption over acyclovir
Mechanism: Converts to acyclovir in the body, inhibiting viral replication
Side Effects: Headache, gastrointestinal upset AAO
Oral Famciclovir (Famvir®)
Class: Nucleoside analogue
Dosage: 250 mg by mouth twice daily for 7–10 days
Purpose: Alternative to acyclovir with less frequent dosing
Mechanism: Converted to penciclovir, blocking viral polymerase
Side Effects: Headache, diarrhea AAO
Topical Ganciclovir Gel 0.15% (Zirgan®)
Trifluridine 1% Eye Drops (Viroptic®)
Class: Thymidine analogue
Dosage: 1 drop every 2 hours (max 9/day) for 7–10 days
Purpose: Kills virus in epithelial cells
Mechanism: Incorporates into viral DNA, causing faulty replication
Side Effects: Corneal toxicity, burning sensation Core EM
Idoxuridine 0.1% Solution or 0.5% Ointment
Class: Nucleoside analogue
Dosage: Solution: 1 drop hourly while awake; Ointment: ribbon every 4 hours and at bedtime
Purpose: Treats dendritic epithelial lesions
Mechanism: Blocks thymidine incorporation into viral DNA
Side Effects: Blurred vision, photophobia, irritation Wikipedia
Vidarabine 3% Ointment (Vira-A®)
Class: Adenosine analogue
Dosage: Ribbon into eyelid 5 times daily for 7–10 days
Purpose: Alternative topical antiviral
Mechanism: Blocks viral DNA polymerase
Side Effects: Mild stinging, local irritation Medscape
Oral Cidofovir (off-label)
Class: Nucleoside phosphonate
Dosage: 1 mg/kg IV or off-label topical 1% once daily
Purpose: Used in resistant cases
Mechanism: Inhibits viral DNA polymerase after phosphorylation
Side Effects: Nephrotoxicity (IV), local irritation (topical) PubMed
Topical Interferon-α (off-label)
Class: Cytokine antiviral
Dosage: 1 million IU/mL 4 times daily for 14 days
Purpose: Adjunct to speed healing
Mechanism: Enhances antiviral immune responses
Side Effects: Mild irritation, conjunctival redness NCBI
Oral Foscarnet (off-label)
Class: Pyrophosphate analogue
Dosage: 40 mg/kg IV every 8 hours for 7–10 days
Purpose: Treats acyclovir-resistant HSV
Mechanism: Inhibits viral DNA polymerase directly
Side Effects: Renal toxicity, electrolyte imbalance Medscape
Dietary Molecular & Herbal Supplements
L-Lysine (1,000 mg/day)
Function: May reduce HSV replication.
Mechanism: Competes with arginine (needed by HSV) for uptake.
Vitamin C (500 mg twice daily)
Function: Supports immune cell function.
Mechanism: Antioxidant that scavenges free radicals.
Vitamin E (400 IU/day)
Function: Protects cell membranes.
Mechanism: Antioxidant preventing lipid peroxidation.
Zinc (15 mg/day)
Function: Enhances antiviral immune response.
Mechanism: Cofactor for immune enzymes and T-cell function.
Selenium (100 µg/day)
Function: Supports antioxidant systems.
Mechanism: Component of glutathione peroxidase.
Omega-3 Fish Oil (1,000 mg/day)
Function: Reduces inflammation on ocular surface.
Mechanism: Modulates eicosanoid pathways.
Curcumin (500 mg twice daily)
Function: Anti-inflammatory and antiviral benefits.
Mechanism: Inhibits NF-κB signaling, reduces cytokines.
Quercetin (500 mg twice daily)
Function: May block HSV entry into cells.
Mechanism: Inhibits viral glycoprotein binding.
Echinacea (300 mg TID)
Function: Immune stimulant.
Mechanism: Increases macrophage activity.
Astragalus (500 mg twice daily)
Function: Supports antiviral immunity.
Mechanism: Stimulates interferon production.
Elderberry Extract (500 mg twice daily)
Function: Inhibits viral replication.
Mechanism: Blocks viral adhesion.
Propolis (500 mg twice daily)
Function: Antiviral and wound-healing.
Mechanism: Flavonoids inhibit viral enzymes.
Green Tea Extract (250 mg/day)
Function: Antioxidant, may lower recurrence.
Mechanism: Epigallocatechin gallate (EGCG) blocks viral replication.
Garlic Extract (500 mg/day)
Function: Broad-spectrum antiviral.
Mechanism: Allicin interferes with viral assembly.
Licorice Root (400 mg/day)
Function: Antiviral and anti-inflammatory.
Mechanism: Glycyrrhizin inhibits viral penetration.
Regenerative & Stem-Cell-Derived Therapies
Autologous Serum Eye Drops (20%)
Dosage: 4 times daily for 4 weeks.
Function: Delivers growth factors and vitamins.
Mechanism: Promotes epithelial cell migration and healing.
Umbilical Cord Serum Drops (100%)
Dosage: 4 times daily for 4 weeks.
Function: Rich in anti-inflammatory cytokines.
Mechanism: Reduces inflammation and promotes repair.
Amniotic Membrane Extract Drops
Dosage: 3 times daily for 2 weeks.
Function: Supplies natural matrix proteins.
Mechanism: Encourages epithelial regrowth and reduces scarring.
Recombinant Human Nerve Growth Factor (Cenegermin)
Dosage: 20 µg/mL, 6 times daily for 8 weeks.
Function: Restores corneal nerve function.
Mechanism: Stimulates sensory nerve regeneration.
Platelet-Rich Plasma Eye Drops
Dosage: 4 times daily for 4 weeks.
Function: High in growth factors and cytokines.
Mechanism: Promotes rapid epithelial healing.
Mesenchymal Stem Cell-Derived Exosome Drops
Dosage: 1 drop daily for 4 weeks (experimental).
Function: Provides regenerative signals.
Mechanism: Exosomes deliver microRNAs and proteins that aid repair.
Surgical Procedures
Corneal Epithelial Debridement
Procedure: Gentle scraping of dead epithelium under anesthesia.
Why: Removes infected cells, allowing healthy regrowth.
Phototherapeutic Keratectomy (PTK)
Procedure: Laser removal of the superficial diseased cornea.
Why: Smooths scarred areas and promotes uniform healing.
Superficial Keratectomy
Procedure: Manually lifts and removes diseased epithelial and stromal tissue.
Why: Treats persistent nonhealing geographic ulcers.
Amniotic Membrane Transplant
Procedure: Grafting preserved amniotic membrane onto the cornea.
Why: Provides a biological scaffold for epithelial regeneration.
Penetrating Keratoplasty (Corneal Transplant)
Procedure: Full-thickness donor cornea replaces diseased tissue.
Why: Restores vision when scarring is deep and permanent.
Prevention Strategies
Good Hand Hygiene: Wash hands before touching eyes.
Avoid Eye Rubbing: Stops spread of virus to other eye.
Proper Contact Lens Care: Disinfect and replace cases regularly.
Use UV-Blocking Sunglasses: Shields eyes from harmful sunlight.
Manage Stress: Reduces risk of viral reactivation.
Adequate Sleep: Supports immune defenses.
Balanced Diet: Fuels a strong immune system.
Avoid Sharing Towels or Makeup: Prevents cross-contamination.
Maintain Eyelid Hygiene: Reduces bacterial superinfection risk.
Prophylactic Antiviral Therapy: For patients with frequent recurrences, a low-dose maintenance course of acyclovir or valacyclovir can cut recurrence rates by up to 50% Wikipedia.
When to See a Doctor
Sudden, severe eye pain or vision loss
Ulcers not improving after 48 hours of treatment
Increased redness, discharge, or light sensitivity
Fever or rash suggestive of systemic HSV
If pregnant or immunocompromised
What to Eat and What to Avoid
Eat: Citrus fruits (vitamin C), leafy greens (antioxidants), lean protein (repair), omega-3 rich fish, yogurt (probiotics).
Avoid: Nuts and chocolate (arginine-rich), processed sugars, alcohol, caffeine, and refined carbs that can impair immunity.
15 Frequently Asked Questions
What causes HSEK?
HSV travels from the trigeminal ganglion to infect corneal epithelial cells.Is it contagious?
Yes—virus is present in tears and can spread by touch.How long does it last?
With treatment, most episodes heal in 1–2 weeks.Can it recur?
Yes—up to 50% of patients have repeat outbreaks without prophylaxis.Can it cause blindness?
If untreated or recurrent, stromal scarring can impair vision permanently.Are eye drops or pills better?
Oral antivirals avoid corneal toxicity and are equally effective.Can I wear contact lenses?
No—stop lens use until full healing to prevent trauma.Are steroids safe?
Steroids are contraindicated in active epithelial disease.Is there a vaccine?
No licensed vaccine for HSV keratitis yet.Can I drive?
Avoid driving if vision is blurred or light sensitivity is severe.Does stress trigger outbreaks?
Yes—stress management can reduce recurrence risk.Can herbal remedies help?
Some (like L-lysine) may reduce recurrences, but always discuss with your doctor.What if I’m pregnant?
See your doctor urgently—some antivirals are safer than others in pregnancy.When is surgery needed?
For nonhealing ulcers or deep scarring that threaten vision.How can I prevent recurrence?
Good hygiene, stress control, balanced diet, and possibly low-dose antiviral maintenance.
Disclaimer: Each person’s journey is unique, treatment plan, life style, food habit, hormonal condition, immune system, chronic disease condition, geological location, weather and previous medical history is also unique. So always seek the best advice from a qualified medical professional or health care provider before trying any treatments to ensure to find out the best plan for you. This guide is for general information and educational purposes only. Regular check-ups and awareness can help to manage and prevent complications associated with these diseases conditions. If you or someone are suffering from this disease condition bookmark this website or share with someone who might find it useful! Boost your knowledge and stay ahead in your health journey. We always try to ensure that the content is regularly updated to reflect the latest medical research and treatment options. Thank you for giving your valuable time to read the article.
The article is written by Team RxHarun and reviewed by the Rx Editorial Board Members
Last Updated: August 06, 2025.
