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Johns Hopkins Symptoms and Remedies

Johns Hopkins Medicine

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Conjunctivitis

What is it?

Conjunctivitis is an inflammation of the mucous membranes (conjunctiva) that line the inner surface of the eyelids and the whites of the eyes. It may be triggered either by an infection or an allergic reaction. Known as pinkeye because the blood vessels in the whites of the eyes dilate and redden, conjunctivitis is highly contagious when caused by an infection. Although usually not serious, conjunctivitis should be treated promptly to prevent possible complications and transmission to others. With treatment, conjunctivitis generally disappears within two or three weeks.

What Causes It?

  • Bacterial or viral infections are the most common causes of conjunctivitis.
  • Allergies (to such things as pollen, cosmetics, and contact lens cleaning solution) are a possible cause.
  • Air pollution or chemical irritants may lead to conjunctivitis.
  • Cervical infections (chlamydia, genital herpes, or gonorrhea) in a pregnant woman may result in potentially blinding conjunctivitis in the baby.
  • A partially blocked tear duct is a possible cause.

Prevention

  • Try never to touch the eyes when, for example, handling contact lenses.
  • Wash your hands often with soap and warm water.
  • Change towels and pillowcases often.
  • Do not share towels.
  • Do not share eye makeup; replace cosmetics every four to six months.
  • Avoid substances that trigger eye irritation.

Diagnosis

  • The diagnosis can generally be made by the typical findings on physical examination.
  • Swab samples may be taken and cultured to identify the type of bacterial infection involved.

How to Treat It

  • First, consult a doctor or ophthalmologist to confirm the diagnosis. It is important to determine whether infectious conjunctivitis is bacterial or viral in origin. Bacterial conjunctivitis is the more serious of the two and requires treatment; viral conjunctivitis typically resolves on its own, without complication.
  • Your doctor may prescribe antibiotic or steroid eyedrops or ointments. Use as directed and be careful not to allow the tip of the eyedrop bottle to touch the eyes.
  • For infectious conjunctivitis, soak a clean cloth in warm water, wring it dry, and apply it to the eye.
  • For allergic conjunctivitis, apply cool compresses to the eye. Antihistamines may be recommended.

When to Call a Doctor

  • Call a doctor if conjunctivitis symptoms do not improve after three or four days of treatment, especially if fever, increased pain, or changes in vision develop. In the case of bacterial conjunctivitis, prompt treatment will avert complications.