Redness of the eye is a common symptom which may have a number of causes. Red eyes occur when blood vessels become enlarged or there is bleeding. When the cause of redness is clear and unambiguous, the condition can be treated at home.
Redness of the eye is most often caused by dryness of the eyes, lack of sleep, long periods of work at close proximity, e.g.reading and computer work, or alcohol. It may be caused by viral or bacterial conjunctivitis, a foreign body, an allergy, chemical irritation or UV light.
A different kind of redness is associated with subconjunctival haemorrhage, also called suggillation. Subconjunctival haemorrhage is bleeding from a small blood vessel over the whites of the eye (also called sclera). The entire white of the eye or part of it is very red. A subconjunctival haemorrhage can occur spontaneously or as a result of rubbing, straining or minor injury. A severe blow on the eye may cause more serious damage to the eye in addition to subconjunctival haemorrhage. The redness of an eye may also be a sign of an incipient eye condition.