See also: Eye color
Red eyes, injected with blood, are a symptom related to different conditions, accumulated by inflammation and dilation of the ocular capillaries; some of these are absolutely benign, others are a source of concern and others still represent a real medical emergency.
Causes of red eyes
The most common cause of red eyes is crying, both of emotional and irritative origin (due to allergic phenomena, intense sun exposure, dust, presence of foreign bodies or other conditions). Excessive alcohol consumption also contributes to dilating the cutaneous and ocular capillaries, causing the characteristic redness.
Blood-streaked eyes can signal a "cold" illness, such as the flu or the common cold. The cough, in particular, especially when intense, can determine the rupture of the small capillaries that supply the sclera oculars.
In patients treated with oral anticoagulants (such as Coumadin ® or Sintrom ®), the appearance of bloodshot red eyes may be a sign of overdose; in this case, small bleeding may also occur at the level of the skin, gums (during tooth brushing), or nose (epistaxis). In this case it is good to communicate the symptoms to your doctor, for the evaluation of the protombin time (INR) and the possible adjustment of the doses.
If the eye is more pink than red, irritated and watering, it could be conjunctivitis, an inflammatory process - caused by infections, allergies or chemical / physical irritations - on the conjunctiva. Therefore, in the presence of severe eye irritation and abundant or purulent secretions, it is advisable to consult the doctor; in this case, in fact, conjunctivitis probably has an infectious origin and as such can spread to the other eye or be easily transmitted to other people. In the meantime, care should be taken to wash your hands thoroughly and avoid contact between them with the other eye.
In blepharitis, red eyes are typically accompanied by itching and swelling of the eyelid margins, which may appear greasy or sprinkled with scabs. Also in this case the etiology can be bacterial.
Acne rosacea, a fairly common acne form - which affects the face by increasing sebaceous secretion and dotting it with pimples - in more than half of the cases it also affects the eyes, causing tearing, dry eyes, photosensitivity, discomfort and red eyes. If left untreated, ocular rosacea can damage eyesight, so medical consultation is also important in this case.
Especially in the elderly with hypertension, red eyes, streaked with blood and associated with severe headache, blurred vision, nausea, vomiting and mental confusion, can be the consequence of an attack of acute glaucoma. This is a real medical emergency, which in the absence of adequate care can compromise the sight up to blindness; therefore the immediate request for medical aid is required.
