The most common cause of red eyes – external stimuli. Cosmetics, cigarette smoke, pollen. It can also be due to eye strain when reading with poor lighting, with a stay at the computer, TV. Fatigue, insufficient sleep, stress, wearing contact lenses can also lead to inflammation of the eye. Another cause may be any of the disease.The most common disease – conjunctivitis, when it is inflamed the mucous membrane of the eye. There are several varieties of this disease. If pathogens are bacteria: pneumococcus, Staphylococcus, Streptococcus, gonococcus, it is a bacterial conjunctivitis. It is characterized by copious lacrimation and photophobia. The conjunctiva swells, turns red, the visible petechial hemorrhages. When the cause of redness are different allergens: cosmetics, household chemicals, chemical and physical factors, it is allergic conjunctivitis. Its manifestations are different, for example, there is a burning sensation, pain, itching, lacrimation. May abundant mucous discharge. There are also adenovirus, epidemic, fungal conjunctivitis. All forms are characterized by common symptoms – redness, swelling of the conjunctiva of the eyelids, presence of purulent or mucous discharge. Revit – the defeat of the choroid of the eye. Distinguish the front and back of the eyeball. Inflammation of the anterior part of the ciliary and the iris is called iridocyclitis (anterior hewit), and back or choroid – chorionic (rear hewit). Redness just eyes called panuveitis. The cause of the disease is an infection that penetrates their external environment or from internal sources of the common diseases. The most dangerous proveit. There are several types of this disease: acute, chronic, peripheral. The symptoms of this disease such as conjunctivitis, but still may experience decreased vision.Also this can be caused by: glaucoma, increased intraocular pressure, there is pain, reduced clarity of vision, and other diseases.