Red eyes can make a person feel self-conscious or worried about the cause. When talking with others, people look into the eyes of the other person. Therefore, red eyes are can be quite noticeable. Bloodshot eyes or red eyes can make a person look tired or unhealthy. What causes red eyes?
If dirt gets into the eye, the eye may turn red from irritation. The eye is likely to water as well. This is the body’s natural way to cleanse the eye and remove the dirt. After the dirt is removed, the eye redness subsides.
Allergies often cause a person’s eyes to redden. An allergic reaction irritates the lining, or conjunctiva, or the eye which causes red eyes. The condition of red eyes due to an allergy is sometimes called allergic conjunctivitis. Antihistamines are sometimes used to alleviate this condition though it usually clears rather quickly without treatment.
Conjunctivitis, also known as pink eye, is a common cause of red eyes. Pink eye is caused by bacterial or viral infections. This condition usually clears on its own, but many schools and workplaces require a note from the doctor to prove the condition is being treated because pink eye can be contagious.
Another common cause of red eye is a burst blood vessel in the eye. Pressure from a sneeze or vomiting may rupture one of the small blood vessels near the surface of the eye. The blood pools under the conjunctiva. This appears as a red spot on the eye known as a subconjunctival hemorrhage.
Wearing a contact lens that is dirty or damaged irritates the conjunctiva and causes eye redness. Optometrists warn against wearing dirty or damaged contact lenses. Even tiny knicks or tears in the contact lens can cause eye irritation. Disposable contact lenses help alleviate this problem since a damaged lens can be easily replaced with a new one.
Dry eye is a relatively common eye condition that is characterized by insufficient tear production of the eyes. When the surface of the eye becomes dryer than usual from this condition, the surface of the eye often becomes irritated and red.
Infection of the eyelids caused by a condition called blepharitis often irritates the conjunctiva causing red eyes. Some people have eyelashes that grow too close to the surface of the eye which can cause redness by irritation of the eyelashes rubbing against the conjunctiva. Other medical conditions that affect the eyelids can cause eye redness and irritation.