What is red eye?
Red eye is the result of changes in the blood vessels in your eye that make your eye look red or bloodshot; it may occur in one or both eyes. Red eye is usually caused by irritation, infection or trauma. Even everyday causes, such as coughing, sneezing, crying, and lack of sleep, can lead to redness in your eye. Red eye is often accompanied by other eye symptoms, including burning, itching, soreness, tearing and discharge.
Physical irritation leading to red eye can be caused by smoke, smog or dust in the air or by household cleaning products or personal care products, such as shampoo or soap that get in your eyes. Prolonged wear of contact lenses also causes irritation that produces red eye. Allergies are a very common cause of red eye, whether they are local, such as an allergic reaction to eye makeup, or more generalized, such as hay fever.
Infections and other inflammations may cause redness resulting from blepharitis (inflammation of the eyelid margin) or conjunctivitis (inflammation of the eye surface). Uveitis and iritis, which are inflammations of structures within the eye, are serious, though less common, causes of red eye. Another serious cause of red eye is acute angle-closure glaucoma. A harmless, but sometimes dramatic, dense area of redness in the white of the eye is usually a subconjunctival hemorrhage, caused by breakage of small, superficial blood vessels.
Most red eye is a result of a mild condition and usually resolves on its own. In rare cases, red eye may be a symptom of serious conditions that can threaten your vision and your health. Because your eyes and vision are vital to your quality of life, be sure to see your health care provider if you have any eye symptoms that cause you concern.
Seek immediate medical care (call 911) if you have red eye along with serious symptoms such as sudden changes in your vision, severe pain in your eye, high fever (higher than 101 degrees Fahrenheit), if your red eye was caused by either blunt or penetrating trauma, or if you experience sudden swelling of the face, lips or tongue.
Seek prompt medical care if your symptom of red eye is persistent, recurrent, or causes you concern.
What other symptoms might occur with red eye?
Depending on the cause of your red eye, other parts of your body may also be affected. A variety of symptoms commonly occur along with red eye.... Read more about red eye symptoms
What causes red eye?
In general, anything that irritates or inflames the white part of your eye can cause red eye. The redness you see is usually caused by an increase in the size of small vessels in your eye, which allows more blood into the white portion of your eye, making it appear red. Sometimes a bright red patch, called a subconjunctival hemorrhage, appears in the white of your eye as a result of the breakage of small, superficial blood vessels.... Read more about red eye causes