Understanding Red Eye: Causes
Understanding Red Eye: Causes
Do your eyes sometimes get red and irritated? This could be a sign of irritation or infection. The inside of your eyelid and the white of your eye are covered with a membrane called the conjunctiva. When your eye is irritated or infected, the blood vessels in this membrane swell. This condition is called conjunctivitis. It is also known as red eye or pink eye.
Irritation
Allergies and environmental irritants are common causes of inflamed eyes. Other causes can include:
Injuries
Objects in the eye
Some eye drops
Makeup
Contact lenses
Diseases within the eye
Infection
Viruses and bacteria can cause eye infections. An infection may begin in your eye. It can also start somewhere else in your body, such as your nose or throat. Sexually transmitted diseases can also cause eye infections.
Updated:  
November 08, 2017
Sources:  
Conjunctivitis. UpToDate.
Reviewed By:  
Bogus, William J., OD, FAAO,Haupert, Christopher L., MD