Eyes can become bloodshot for a quite a number of reasons. Whatever the trigger, whether it is trying out new contact lenses for the first time, an eye infection, or the start of hay fever season, bloodshot eyes occur when blood vessels on the surface of the eye become dilated or enlarged. Both the sclera (white of the eye), and the thin membrane which covers the sclera and lines the eyelids, the conjunctiva, contain many tiny blood vessels that are not usually visible. Irritation or damage to these tissues in the eye causes the body to rush blood to this area, a process which allows repair to take place, and it is this increase in blood supply that causes the dilation of blood vessels which result in bloodshot eyes.
When bloodshot eyes are caused by wearing contact lenses the solution can be fairly straightforward. Often, the use of eye drops can be enough to restore moisture and combat the irritating dry eyes that can sometimes result from wearing contact lenses, particularly when trying out a new prescription. However, the most important thing to note is that the first course of action should always be to remove contact lenses when bloodshot eyes occur, after which you should seek a professional medical assessment of the cause of the condition if symptoms persist.
Various infections can cause bloodshot eyes, and some of these have the potential to be serious, and require medical attention. Bacterial conjunctivitis (pink eye) will often require treatment with antibiotics, although this uncomfortable condition rarely has any profound long term effects.
Other conditions like Blepharitis – an inflammation of the eyelids and eyelashes – and Uveitis, an inflammation of the uvea, can also result in bloodshot eyes. Bloodshot eyes are also a symptom of corneal ulcers, which can develop for a number of reasons and again require medical treatment.
As well as resulting from the introduction of various foreign objects to the eye, and infections, bloodshot eyes can also be an indicator of several lifestyle issues. These can range from fatigue and eyestrain to the use of certain medicines, like blood thinning drugs, or the overuse of alcohol, and smoking. Kidney stones and liver disease can also cause bloodshot eyes, as can diabetes or being pregnant. A poor diet and vitamin deficiencies can again be triggers, or you may simply be stressed and anxious. Viruses such as glandular fever and mumps can also cause bloodshot eyes. If the condition occurs late at night or early in the morning, and passes quickly, you can chalk it down to the pace of life, but bloodshot eyes occurring for any length of time should prompt a trip to the doctor.
