bloodshot eyes causes are many allergens, dust particles, fumes, or other eye diseases. It is actually a symptom of other eye diseases, not a disease itself. The anterior portion of the eyeball consists of a whitish portion (which is called the sclera) and central cornea. Tiny blood vessels supply the oxygen and nutrition to the anterior part of the eyeball which is located between sclera and conjunctiva. These blood vessels are minute and are mostly invisible. But it becomes visible when blood vessels become swollen.

It is not a worrisome problem unless it is associated with other symptoms like eye pain, irritation, watering eye, poor vision, light insensitivity, or poor sensation. When these symptoms are accompanied by the bloodshot eyes causes, it needs proper medication or treatment to be considered. This is a very common eye condition that doesn’t need any proper treatment and goes away usually. The whitish portion of the eyeball to be reddened, also known as Redeye.
Table of Contents
- How Eyes Become Bloodshot Eyes?
- Bloodshot Eyes Causes
- 1- Dust, fumes, pollen, grains exposure
- 2- Chemical exposure to certain acids
- 3- Overexposure to sun radiation
- 4- Bacterial Infections
- 5- Environmental pollution
- 6- Dryness in eye
- 7- Viral infections
- 8- Keratitis
- 9- Fungal infection
- 10- Overuse of contact lenses
- 11- Poor eye hygiene
- 12- Mishandling of contact lenses
- 13- Sharing of your lenses with others
- 14- Corneal ulcer
- 15- Uveitis
- 16- Poor sleeping time
- 17- Overuse of digital devices at night
- 18- Smoking, alcohol consumption
- Why Do I Wake Up With Bloodshot Eyes?
How Eyes Become Bloodshot Eyes?
When stimuli enter in the eye, the body’s immune system activated immediately against that allergen or particle. Inflammatory mediators like interleukin, cytokines, plasma proteins, macrophages, cytotoxic T cells begin to move towards the eye. These inflammatory mediators engulf the foreign particle and kill them. A little inflammation occurs at that site, oxygen supply also diminished, blood vessels become swollen, and blood oozing out from the blood vessels and spread over the entire whitish portion of the eyeball. It disappeared after 24 hours without any specific treatment.
Bloodshot Eyes Causes
Millions of reasons are there to cause the redness in eyes by dilation of tiny blood vessels. They include
1- Dust, fumes, pollen, grains exposure
As we are living in a polluted environment, lots of dust particles are around us which enter an eye and cause little inflammation, redness, and irritation.
2- Chemical exposure to certain acids
Alkali or acids present in different forms, if exposed to the eye, it may cause severe inflammation, redness, burning sensation, Vision loss or eye pain.
3- Overexposure to sun radiation
Sunlight has thousands of harmful ultraviolet radiation which badly affects your vision and tear film of the eye. It causes dryness in eyes, irritation, discomfort, eye pain, redness, and eye fatigue. So be sure to wear the glasses when you are on go on a sunny day.
4- Bacterial Infections
Many bacteria cause infection in the eye which associated with the bloodshot eyes, mucous discharge from the eye, gluing of eyelids together, impaired vision, burning sensation in the eye. These bacteria can be corynebacteria diphtheria, Neisseria meningitis is, or gram-negative bacteria.
5- Environmental pollution
The environment is full of dust, industrial wastes, smog, greenhouse gases that disturb your tear film. It causes dryness over eyes, burning sensation due to harmful gases, irritation due to smog or carbon monoxide, and eye pain.
6- Dryness in eye
Insufficient production of tear film keeps the eye dry and redness in the eye.
Many viruses like herpes simplex virus and herpes zoster virus cause infection which is associated with watery discharge from the eye, eye pain, redness in the eye, eye discomfort, impaired vision, and insensitivity to light.
8- Keratitis
Keratitis is an inflammation of the cornea. The cornea is a dome-shaped structure in the center of the eyeball which covers the eyeball. When inflammation occurs in the cornea, inflammatory mediators swollen up the blood vessels and the whitish portion turned into reddened.
9- Fungal infection
Bloodshot eyes are also caused by many fungi because of inflammation against the foreign particle ( fungi).
10- Overuse of contact lenses
Overnight use of contact lenses causes redness in eye and eye discomfort because a little inflammation begins to appear due to over wearing off the lens.
11- Poor eye hygiene
Daily wash your eyelids and eyes keep your eye free from dust and allergy. If you don’t wash your eyes, dust particles settled in your eyes and cause damage.
12- Mishandling of contact lenses
Wearing lenses with dirty hands causes damage to lenses. If lenses are not sealed in a bottle, lenses become infected with the environmental particles. Always wash your lenses with the distilled water and then use it.
13- Sharing of your lenses with others
Never share your lenses with your siblings and with your fellows because it can spread infection from one person to another person.
14- Corneal ulcer
A corneal ulcer is actually a loss of corneal tissues which is associated with the inflammation of the cornea. Such eyes are more prone to get infected because of an open pore. Bloodshot eyes are the main feature of corneal ulceration.
15- Uveitis
Inflammation of uveal tract which consists of iris, choroid, and uvea. There is inflammation of the uveal tract which causes redness.
16- Poor sleeping time
Insufficient sleep puts your eyes tired and fatigue due to which your eyes become red and infected.
17- Overuse of digital devices at night
Most students use many digital devices like mobile phones, laptops, computers, etc overnight in dim light. It doesn’t affect only eyesight but also causes a headache, eye pain, eye fatigue, bloodshot eyes, and discomfort.
18- Smoking, alcohol consumption
Cigarette smoke not only bad for lungs but also destroys the eye because its smoke is full of tobacco, carbon monoxide, and tar which affect the tear production of your eye.
Why Do I Wake Up With Bloodshot Eyes?
Lack of sleep or tired eyes become red when you wake up. Lack of sleep actually decreases the oxygen supply to the eye which results in dilation of small eye blood vessels. Dilation of blood vessels and redness of eyes occurs when you have less sleeping hours than your body requirements. The only way to get rid of it, get more sleep and you may use artificial tears.
HP Thoughts: Know some tips for eliminating bloodshot eyes naturally. Read our article for details — Bloodshot Eyes.