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What Is Conjunctivitis?

Conjunctivitis (also called pink eye) is the most common eye infection. It causes soreness and swelling (inflammation) of the skin that lines the eyelid and the white part of the eyeball. One or both eyes can have it. People of any age can get conjunctivitis. It occurs most often in the fall.

Serious complications that threaten sight are very rare.

What Causes Conjunctivitis?

The cause can be infection with bacteria or virus (very contagious) or an allergy to something such as pollen.

The virus is usually the one that causes a common cold. Different bacteria (such as Staphylococcus and Streptococcus) can cause the infection. Direct contact with tears or the infected area, which occurs by placing towels, fingers, or handkerchiefs near the eye, will pass these infections to others.

What Are the Symptoms of Conjunctivitis?

Conjunctivitis produces a red irritated eye with a watery discharge (allergic and viral) or a discharge of mucus and pus (bacterial). Bacterial conjunctivitis also causes soreness and swelling in one eye, slight pain and feeling dirt or grit in the eye, and a slimy discharge that causes lids to crust. It’s most common in children.

Viral conjunctivitis usually causes inflammation and discharge that is more watery than that in bacterial conjunctivitis.

Allergic conjunctivitis produces red, irritated, itchy eyes; small watery discharge; and inflammation of both eyes. Itching is characteristic of allergic conjunctivitis. Allergies can be to pollen, pets, and house dust.

How Is Conjunctivitis Diagnosed?

The health care provider makes a diagnosis from your medical history and an examination of your eyes.

How Is Conjunctivitis Treated?

For bacterial infection, the health care provider will prescribe antibiotic eye drops or ointment. Warm compresses on the eye may also be used.

For viral conjunctivitis, the health care provider may suggest eye drops that help increase moisture in the eye. Antibiotic eye drops or ointment won’t work. Warm compresses on the eye may help.

For allergic conjunctivitis, the health care provider will prescribe eye drops for inflammation. Cold, not hot, compresses may soothe the eye. Decongestant and antihistamines may also be used.

Bacterial conjunctivitis is usually much better within 48 hours of starting therapy. It’s usually over in about 1 week.

Viral conjunctivitis usually improves in 1 to 2 weeks but may take longer.

Symptoms of allergic conjunctivitis may be seasonal.

DOs and DON’Ts in Managing Conjunctivitis:

  • DO avoid direct contact with anyone who has conjunctivitis.
  • DO wash your hands often.
  • DO use separate towels, washcloths, and pillowcases from other family members if you have conjunctivitis.
  • DO throw away old eye cosmetics and don’t share eye cosmetics with others.
  • DO avoid the cause of the allergy, if possible.
  • DO use medicines as directed. If using more than one eye drop, wait between use of each so that the second doesn’t wash the first out.
  • DO call your health care provider if you have severe pain, fever, and blurred vision with conjunctivitis.
  • DON’T touch the infected area or rub your eye.
  • DON’T wear contact lenses until treatment is over. You may need to replace the contact lenses and the container normally used for storing them.

Contact the following sources:

  • American Academy of Ophthalmology
    Tel: (415) 561-8500
  • American Academy of Optometry
    Tel: (301) 984-1441

Copyright © 2016 by Saunders, an imprint of Elsevier, Inc.

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