Suzanne Albrecht, PharmD, MSLIS


US Pharmacist 

In This Article

Viral Conjunctivitis

This is the most common form of conjunctivitis.[11] It is far more common than bacterial conjunctivitis.[5] The three main viral types are adenovirus, herpes simplex virus (HSV), and herpes zoster (HZ) (varicella-zoster virus).[3]

Adenoviral Conjunctivitis

This is the most common type of viral conjunctivitis.[8] It is self-limited, and improvement usually occurs within 5 to 14 days; however, contagion is possible for up to 14 days after the appearance of symptoms.[3,12] Adenoviral conjunctivitis is highly contagious and is spread through direct contact with contaminated hands, medical equipment, pool water, or personal items.[12] Patients must take appropriate measures to reduce the risk of spread.[3]

Adenoviral conjunctivitis may present unilaterally or bilaterally with an acute onset (often sequentially bilateral).[3] Frequently, the patient suffers from a concomitant upper respiratory infection. Symptoms include red, itchy eyes with a watery or mucous discharge.[13] Severe cases may involve conjunctival scarring, symblepharon (adhesion of eyelids to the eyeball), and subepithelial corneal infiltrates.[3,12]

Because it is difficult to differentiate adenoviral conjunctivitis from bacterial conjunctivitis, antibiotics are frequently prescribed.[5,12] There may also be an opportunistic bacterial infection warranting antibiotic use.[5] No antiviral solutions are effective against adenoviruses.[1,3] Artificial tears, topical antihistamines, and cold compresses may alleviate symptoms.[3,12] Topical corticosteroids may be beneficial, but the patient must be monitored closely.[3] If symptoms do not resolve on their own or if there is corneal involvement, the patient should be referred to an ophthalmologist.[12]

HSV Conjunctivitis

HSV occurs in neonates of infected mothers 1 to 2 weeks after birth; it also may occur in sexual partners of infected individuals.[11] Triggers include stress, trauma, infection with another virus, and ultraviolet exposure.[3] HSV is the most common cause of blindness from corneal disease in the U.S.[2,11] The disease presents unilaterally with bulbar conjunctival injection, watery discharge, epithelial keratitis of the cornea or conjunctiva, stromal keratitis, neovascularization, scarring, thinning, perforation, uveitis, trabeculitis, and vesicular rash or ulceration of the eyelids.[3]

HSV usually does not require treatment. Symptoms resolve within 4 to 7 days, unless there are complications. To prevent corneal infection, oral or topical antivirals should be used. Trifluridine 1% solution 5 to 8 times daily or oral acyclovir 200 mg to 400 mg 5 times daily may be used; oral valacyclovir 500 mg 2 to 3 times daily or famciclovir 250 mg twice daily are effective also. Vidarabine 3% ointment is another topical antiviral.[1] Use of topical antivirals for longer than 2 weeks may result in toxicity. Topical steroids are contraindicated.[3]

HZ Conjunctivitis

Patients with chickenpox (or people exposed to it) may develop HZ conjunctivitis. The condition is usually selflimited, with symptom resolution within a few days.[3]

HZ may present unilaterally or bilaterally. Symptoms include bulbar conjunctival injection and watery discharge. Punctate keratitis may result in primary infection. Limbal vesicles may form, especially with primary disease. Vesicle formation may result in necrosis and scarring on the eyelid margins, conjunctiva, and corneal stroma.[3]

Topical antibiotics are sometimes used to prevent secondary bacterial infections. There are no effective topical antivirals, but immunocompromised patients may be given acyclovir 800 mg 5 times daily for 7 days, valacyclovir 1,000 mg every 8 hours for 7 days, or famciclovir 500 mg 3 times daily for 7 days.[3]