What is Pink Eye (Conjunctivitis)?

Pink Eye, or conjunctivitis, is redness and inflammation of the membranes that line the eyelid and the whites of the eyes. Pink eye is very common and typically does not cause changes in vision. You can have conjunctivitis in one or both eyes. It is easily treated, but without treatment, vision can be damaged.

What causes Pink Eye (Conjunctivitis)?

There are many causes of Pink Eye. Pink Eye can be caused by a bacterial or viral infection, or it can be the result of an allergic reaction or chemical irritation of the eye. Viral and bacterial pink eye are both contagious and spread very easily.

Viral conjunctivitis usually spreads through contact with contaminated tears or nasal fluids. Viral conjunctivitis can also be part of a broader group of symptoms involving the upper respiratory tract like a common cold or sore throat. Viral pink eye is typically more common than bacterial pink eye.

Conjunctivitis can also be an allergic reaction due to something in the air, such as pollen or dust; something put into the eye, such as contact lens solutions. Chemical conjunctivitis can be caused by spray perfumes, deodorants, household cleaners, smog and industrial pollutants that irritate the conjunctiva.

Symptoms of Pink Eye

Common symptoms for all forms of pink eye are:

  • Redness of the eye (“bloodshot” appearance)
  • Itchiness and irritation
  • Drainage from the eye
  • Mild sensitivity to light
  • Typically affects one eye, but can easily spread to other eye
  • In viral pink eye, the eyelids are also usually swollen and red. The eye drainage is typically very clear and watery, and itching is usually severe.

In bacterial pink eye, there is usually a thick, sticky, yellowish discharge. The discharge may accumulate into crusts on the eyelids and may make the eyelids stick together after sleep.

In chemical conjunctivitis, depending on the chemical irritant, there can be severe eye irritation and pain.

How is it treated?

Doctors can often determine the type of conjunctivitis by taking a careful history of when and how the eye symptoms began and by examining the eyes to look for specific signs, such as swelling or discharge.

Viral pink eye will not respond to antibiotic treatment. It typically goes away on its own in about 7 to 10 days.

Bacterial pink eye is treated with antibiotics, usually given as eye drops or eye ointments.

Allergic conjunctivitis is treated by managing allergens and treating the irritated eyes with decongestants, antihistamines.

To learn more: Medicinenet