Why Are My Eyes Red: 30 Possible Causes

Why Are My Eyes Red: 30 Possible Causes

Why Are My Eyes Red: 30 Possible Causes

By Island Hospital | Oct 16, 2019 11:20:41 AM

28-year-old, Lina, thought that her blood-shot eyes was heredity, and probably worsened by her habitual boozing and late nights with buddies in smoke-filled clubs. But as days passed, her condition worsened, she could not concentrate on her work and she kept getting sicker. It was only when she was forced by her mum to go see the ophthalmologist (eye doctor) when they discovered that her red eyes were caused by another medical condition, sarcoidosis (an inflammatory disease that affects multiple organs in the body, but mostly the lungs and lymph glands).

It is so easy to dismiss red eyes and think that they are due to only harmless lifestyle and environmental factors. Underlying, however, they could be symptoms of serious conditions which we are not aware of until we seek medical help.

Here are some things you need to know about red eyes.

Your eyes appear red when the tiny blood vessels on the surface of the eyes increase in size and make the eye look bloodshot.

Many things can cause it, like a night of heavy drinking, or an injury to your eye. But if you did not have too much alcohol, or scratch or poke your eyeball recently, there could be other causes. Red eyes (or red eye) is a condition where the sclera (white part of the eye) has become reddened or “bloodshot.”

The appearance of red eye can vary widely. It can look like there are several squiggly pink or red lines on the sclera or the entire sclera may appear diffusely pink or red.


Red eye can occur in one or both eyes, and it can be associated with several symptoms, including:


  • Blurry vision
  • Burning sensation
  • Excess tearing
  • Dryness
  • Irritation like gritty feeling
  • Itch
  • Pain
  • Sensitivity to light
  • Watery eyes


In some cases, bloodshot eyes may have no symptoms other than redness.

Red or bloodshot eyes are very common and have many causes. Red eye usually is a symptom of other eye conditions that can range from harmless to serious.


The redness can be caused by dilation of tiny blood vessels that are located between the sclera (white part of the eye) and the overlying clear conjunctiva (clear membrane) of the eye.


These tiny blood vessels (many of which are normally not seen) can become swollen because of environmental or lifestyle-related factors or because of specific eye issues.


Typically, red eyes usually are caused by


    1. Allergy,
    2. Alcohol consumption
    3. Common eye infections such as pink eye (conjunctivitis),
    4. Digital eye strain (from long hours of being exposed to blue-light screens, like computers and smart phones),
    5. Eye fatigue,
    6. Insufficient sleep
    7. Over-wearing of contact lenses,
    8. Smoking (of tabacco or marijuana)


Environmental causes of red, bloodshot eyes include:


    1. Airborne allergens (causing eye allergies),
    2. Airborne fumes (gasoline, solvents, etc.),
    3. Air pollution,
    4. Chemical exposure (chlorine in swimming pools, etc.),
    5. Dry air (dry climates, airplane, office buildings, etc.),
    6. Dust,
    7. Smoke (fire-related, second-hand cigarette smoke, etc.)


However, redness of the eye sometimes can signal a more serious eye condition or disease, such as


    1. Abrasions or burns to the cornea,
    2. Bell’s palsy (Inflammation of the facial nerve that causes one side of a person’s face not to move),
    3. Corneal ulcer,
    4. Eye infections,
    5. Eye trauma or injury,
    6. Fungi,
    7. Glaucoma (often linked to a build-up of pressure inside the eye),
    8. Juvenile idiopathic arthritis ( the most common type of arthritisin children),
    9. Leukemia ( cancer of the blood or bone marrow),
    10. Parasites,
    11. Recent eye surgery (LASIK, cosmetic eye surgery, etc.),
    12. Sarcoidosis (an inflammatory disease that affects multiple organs in the body, but mostly the lungs and lymph glands),
    13. Uveitis (inflammation of the uvea — the middle layer of the eye that consists of the iris, ciliary body and choroid),
    14. Viruses,
    15. Widespread infection

There is too much at stake when it comes to our eyes. Let us help to give you the facts and identify the fads. A visit to our ophthalmologist can reveal much about your eye health so you can take on the challenges ahead in life, living it to the fullest.


For more information on our ophthalmologists or to make appointment:



Our physicians and clinicians specialise in diseases and conditions affecting the eye and maintaining visual health.


Our centre is fully equipped with updated equipment to perform LASER eye surgery, refractive lens exchange, retina surgery and treatment of glaucoma and cataracts.


We provide routine eye examinations to the most delicate and complex surgery for children and adults, including medical and surgical care for simple and complex vision disorders, diagnostic testing and surgeries to fix eye disorders.