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Infectious Conjunctivitis

(Pink Eye; Pinkeye)


The Manual's Editorial Staff

Reviewed/Revised Apr 2022 | Modified Sep 2022
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The conjunctiva is the clear, thin tissue that lines the inside of your eyelid and covers the white of your eye. Conjunctivitis is inflammation (swelling and irritation) of your conjunctiva.

The Conjunctiva

What is infectious conjunctivitis ?

Infectious conjunctivitis is caused by infection with a variety of bacteria and viruses. It's often called pinkeye because your eyes turn pink or red.

  • Infectious conjunctivitis spreads easily from one eye to the other, as well as from person to person

  • It's usually caused by a virus

  • Viral conjunctivitis (caused by a virus) lasts 1 to 2 weeks and goes away on its own

  • If you have bacterial conjunctivitis, doctors will give you antibiotic eye drops

  • To avoid spreading conjunctivitis to others, wash your hands often and avoid sharing towels, washcloths, and bedding

Other things besides infections can cause conjunctivitis. For example, a speck of dirt, contact lens, or makeup can irritate and inflame the conjunctiva. Allergies sometimes cause allergic conjunctivitis Allergic Conjunctivitis The conjunctiva is the clear, thin layer that covers the white of your eye and the inside of your eyelids. Conjunctivitis is inflammation (swelling and irritation) of your conjunctiva. Allergic... read more .

What are the symptoms of infectious conjunctivitis?

Symptoms usually start in one eye and then spread to the other. Sometimes the infection comes on while you have a cold.

Typical symptoms include:

  • Pink or red eyes

  • Irritated eyes

  • Watery eyes

Sometimes, the liquid coming from your eyes is white or yellow like pus. It may be thick rather than watery. You might wake up with your eyes stuck shut. Washing your eyes with warm water gets them unstuck easily.

Sometimes you may also notice:

  • Light bothers your eyes

  • Your vision is blurry because of all the liquid in your eyes

If it's caused by bacteria, it's likely that:

  • What comes out of your eye will be thick, sticky, and white or yellow (pus)

  • Your eye may be glued shut when you wake up in the morning

  • Pus coming from the eye

  • Swollen eyelid

How can doctors tell if I have infectious conjunctivitis?

Doctors can tell based on your symptoms and an eye exam. If doctors think chlamydia, gonorrhea, or another problem may be causing your eye problems, they’ll take a sample from your eye and do tests.

How do doctors treat infectious conjunctivitis?

If the cause is viral:

  • Your symptoms will go away on their own in 1 to 2 weeks

  • To soothe an irritated eye, put warm or cool washcloths on it

  • If you have blurred vision or sensitivity to light, doctors may give you corticosteroid eyedrops

If doctors think your infectious conjunctivitis might be caused by bacteria, they'll give you antibiotic eye drops or ointment.

For a newborn, doctors will:

  • Give the newborn a shot of antibiotics if the baby has conjunctivitis caused by gonorrhea or chlamydia

  • Also treat the baby's parents

To prevent conjunctivitis, doctors give newborn babies eye drops or ointment right after birth.

How can I keep infectious conjunctivitis from spreading?

If you have infectious conjunctivitis, take these steps to keep from spreading it:

  • Wash your hands with soap and water or use hand sanitizers often and especially before and after cleaning your eye or putting medicine in your eye

  • Don't touch your eyes

  • Don't share towels, washcloths, and bedding with others

  • Stay home from school or work for a few days

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