Conjunctivitis, also known as pinkeye, is an inflammation of the conjunctiva, the thin, transparent membrane covering the inside of the eyelid and the outside of the white part of the eye.1 This condition afflicts patients of all ages, but is most commonly seen in children. Conjunctivitis can occur in 1 or both eyes and is often highly contagious.2

Although this condition is usually a minor infection, newborns born to mothers with chlamydia and/or gonorrhea can develop a serious infection called ophthalmia neonatorum.3 To preserve eyesight, this condition must be treated immediately. To prevent damage from this condition, clinicians give antibiotic ointment or eyedrops to all babies immediately after birth.1,3

Causes
Conjunctivitis can be caused by allergies, bacteria, certain diseases (such as gonorrhea and chlamydia previously mentioned), chemical exposure, fungi, parasites (albeit rarely), and the use of contact lenses (especially extended-wear lenses).3 Only bacterial and viral conjunctivitis and ophthalmia neonatorum are infectious.2

Allergic conjunctivitis frequently occurs in patients suffering from seasonal allergies when an allergen comes into contact with the eye.

Giant papillary conjunctivitis is a form of allergic conjunctivitis resulting from the chronic presence of a foreign body in the eye. Examples include contact lenses, an exposed suture, or a glass eye.2

Bacterial conjunctivitis is highly contagious and typically caused by staphylococcal or streptococcal bacteria.2 This bacteria can be transferred by contact with one’s own body, physical contact with others, insects, touching contaminated objects, or using contaminated products such as makeup or moisturizers.2

Viral conjunctivitis is the most common form of conjunctivitis4 and is ordinarily caused by the same viruses that cause the common cold. Being close to a coughing or sneezing person can result in pinkeye, as can having an infection move from one’s own mucous membranes.2

Chemical conjunctivitis can be caused by irritants such as chlorine, soaps, smoke, and fumes.1

Symptoms
Allergic conjunctivitis commonly affects both eyes and is marked by inflammation, tearing, and mild to intense itching due to the body’s release of histamines.

Viral or bacterial conjunctivitis can affect 1 or both eyes.5 The most common symptom is a gritty feeling in the eye. Other symptoms include redness of the eye, sensitivity to light, and swollen eyelids. Viral conjunctivitis is usually accompanied by a watery discharge and involvement of lymph nodes, whereas bacterial conjunctivitis is marked by a purulent discharge without nodal involvement. This discharge often forms a crust across the eyelids overnight.6 If the discharge is particularly thick, it may blur vision. Once the discharge is washed away, however, vision returns to normal.

Diagnosis
A thorough patient history tells a clinician about a patient’s symptoms, duration of the condition, and contributing factors. Physical examination of the conjunctiva and external eye tissue using a lighted magnifier and evaluation of the inner structures of the eye may provide a differential diagnosis (Online Table7) and ensure that no other tissues are affected. The clinician may swab a stain across the surface of the eye to verify there are no injuries to the eye. Physical examination may also include a visual acuity test to determine the condition’s effect on vision.6,7 

Table: Conjunctivitis Differentiating Features
Etiology Discharge Eyelid Edema Node Involvement Itching
Allergic Watery Mild/severe None Mild/intense
Bacterial Purulent Moderate None None
Viral Clear Minimal Often None
Adapted from reference 7.

Treatment
The type of conjunctivitis dictates treatment. Allergic conjunctivitis can be treated with ophthalmic or oral antihistamines. If the condition is severe, patients should speak to their clinician about immunotherapy for long-term relief.

Bacterial conjunctivitis is treated with antibiotics, which are available as ophthalmic drops or ointments, or oral antibiotics. Topical antibiotics need to be applied to the inside of the eye without touching the applicator to the eye. They are dosed 3 or 4 times daily for 5 to 7 days. Patients should be advised to finish the course of all antibiotics and can usually return to daycare, school, or work after they have been on the antibiotics for 24 hours.8

Viral conjunctivitis usually lasts from 4 to 7 days. Normally, a clinician will just let this condition run its course, but some clinicians may prescribe an antiviral ophthalmic agent. Once the infection begins to improve, the patient can return to daycare, school, or work, usually in 3 to 5 days.8

Conjunctivitis caused by irritants should be treated by washing out the affected eye(s) with water for 5 minutes to remove the material from the eye. If the substance is an acid or alkaline material, such as bleach, immediately rinse the eyes and call a clinician.8

Symptom Relief
Conjunctivitis symptoms may improve with compresses, but patients should be advised that viral and bacterial conjunctivitis can spread from one eye to the other; therefore, separate compresses should be used for each eye. Recommend warm compresses for infective conjunctivitis and cool compresses for allergic or irritative conjunctivitis.6

Eye washes and artificial tears also can be used for symptom relief, but counsel patients to ensure that these items are sterile. Eyedrops promoted to reduce redness may irritate the eye further and should not be used.8

Complications
Conjunctivitis is typically not dangerous and is usually self-limiting or clears up after a short course of antibiotic therapy. Conjunctivitis resulting from gonorrhea, chlamydia, or certain strains of adenovirus, however, may cause corneal scarring.8

Prevention
Irritative conjunctivitis can be prevented by protecting the eyes from dirt and other irritating materials, avoiding the use of makeup, and removing contact lenses every night at bedtime.8

Frequent hand washing is the best way to avoid getting and spreading pinkeye. Also, avoid touching the face and sharing makeup, towels, and pillowcases. Throw away all eye makeup, and start using new makeup when the infection clears. Wash all towels, sheets, and pillowcases in hot water with detergent.8 Wear glasses instead of contact lenses. Do not rub the infected eye(s). Do not use the same eyedrops in an infected and an uninfected eye.

Stay home from school and work until the infection clears or until antibiotics have been taken for 24 hours. Disinfect household items such as doorknobs, remote controls, light switches, kitchen and bathroom knobs and handles, and telephones.


Dr. Kenny earned her doctoral degree from the University of Colorado Health Sciences Center. She has 20+ years’ experience as a community pharmacist and works as a clinical medical writer in Colorado Springs, Colorado. Dr. Kenny is also the Colorado education director for the Rocky Mountain Chapter of the American Medical Writers Association.

References
  1. Pinkeye (conjunctivitis). KidsHealth.org website. kidshealth.org/parent/infections/eye/conjunctivitis.html. Accessed November 23, 2015.
  2. Conjunctivitis. American Optometric Association website. aoa.org/patients-and-public/eye-and-vision-problems/glossary-of-eye-and-vision-conditions/conjunctivitis?sso=y. Accessed November 23, 2015.
  3. Conjunctivitis. MedlinePlus website. nlm.nih.gov/medlineplus/ency/article/001010.htm. Accessed November 23, 2015.
  4. Choosing wisely part 3: antibiotics for pink eye. American Academy of Ophthalmology website. geteyesmart.org/eyesmart/eye-health-news/choosing-wisely-antibiotics-for-pink-eye.cfm. Published June 10, 2013. Accessed November 23, 2015.
  5. Pink eye (conjunctivitis). Mayo Clinic website. mayoclinic.org/diseases-conditions/pink-eye/basics/definition/con-20022732. Accessed November 23, 2015.
  6. Conjunctivitis. University of Maryland Medical Center website. umm.edu/health/medical/altmed/condition/conjunctivitis. Accessed November 23, 2015.
  7. Roat MI. Overview of conjunctivitis. Merck Manual website. merckmanuals.com/professional/eye-disorders/conjunctival-and-scleral-disorders/overview-of-conjunctivitis. Accessed November 23, 2015.
  8. Conjunctivitis (pinkeye). WebMD website. webmd.com/eye-health/eye-health-conjunctivitis. Accessed November 23, 2015.