What causes red eye?
There are many things that can cause a red eye.
It could be that you have been wearing contact lenses for too long or staring at a computer screen for a long time without a break.
Red eyes can also be caused by allergies, blepharitis (inflamed eyelid), conjunctivitis (pink eye), dry eye, eye injury, or glaucoma.
Environmental causes of bloodshot eyes include;
- Airborne allergens
- Air pollution
- Smoke, including second-hand cigarette smoke
- Dry air, including from airconditioned offices, or a plane cabin
- Chemical exposure, chlorine in swimming pools can cause irritation
- Overexposure to sunlight
When pollen, pet dander, dust, or certain chemicals found in makeup or contact lens solutions get into a person’s eye or body, their immune system reacts. The body releases histamine to fight off the allergens, which also makes the blood vessels in your eyes get larger and your eyes can become red, watery, and itchy.
When eyes do not produce enough tears, or produce tears that lack lipids, dry eye is the result.
Tears keep your eyes healthy and comfortable. Dry eye symptoms can include stinging or burning, lots of tears followed by periods of dryness, and sometimes a mucus discharge.
Dry eye can be painful, and your eyes may be red.
Anyone can get dry eye, but its more common in women, especially those who have gone through menopause. As people age, they produce less of the lipid part of tears, which puts them at greater risk for dry eye.
Conjunctivitis happens when the membrane covering the insides of your eyelids and the white part of your eye, called the conjunctiva, becomes inflamed.
It is a very common eye infection and children quite often experience this type of infection.
Conjunctivitis can be caused by allergies, bacteria or a virus. Viral eye infections, the most common, tend to improve on their own, and don’t require prescription medication. Bacterial eye infections require antibiotics. Both types of infection, are extremely contagious and spread easily.