Red eyes are a common symptom that can be caused by various reasons. Redness of the eyes can indicate a wide range of underlying health conditions and can range from a mild irritation to a severe eye infection.

This article provides a comprehensive list of the most common causes and symptoms of red eyes.

Allergies

Allergies are a common cause of red, itchy eyes. When the body comes in contact with an allergen such as pollen, pet dander, or dust mites, the immune system releases histamines in response.

These histamines cause the blood vessels in the eyes to dilate, leading to redness, itching, and swollen eyes. Allergic conjunctivitis is a common form of this condition.

Dry Eyes

Dry eyes are a condition in which the eyes do not produce enough tears. A lack of tears can cause the eyes to become dry and inflamed, which can lead to redness, irritation, and a feeling of something in the eye.

This condition can be caused by a variety of factors, including aging, certain medications, and medical conditions such as rheumatoid arthritis and Sjogren’s syndrome.

Eye Infections

Eye infections can also cause red eyes. Conjunctivitis, or pink eye, is a common eye infection that causes redness, discharge, itching, and swelling of the eyes.

Other types of eye infections, such as corneal ulcers, can also cause redness and pain in the eyes.

Eye Strain

Eye strain is a common cause of red eyes. This condition often occurs when you spend too much time focusing on a computer screen, reading, or driving.

The muscles in the eye can become tired and inflamed, leading to redness, blurred vision, and headaches.

Foreign Objects

Foreign objects such as dust, sand, or other debris can get into the eye, causing redness, irritation, and watering of the eyes. In some cases, the object may scratch the surface of the eye, leading to pain and discomfort.

Glaucoma

Glaucoma is a condition that damages the optic nerve of the eye, leading to vision loss. This condition can also cause redness, pain, and a feeling of pressure in the eyes. If left untreated, glaucoma can lead to permanent vision loss.

Overuse of Contact Lenses

Wearing contact lenses for extended periods can cause redness of the eyes.

This condition, known as contact lens-induced red eye, can be caused by a variety of factors, including poorly fitting contact lenses, the buildup of bacteria on the lens, and an allergic reaction to the contact lens solution.

Tiredness or Lack of Sleep

Tiredness or lack of sleep can also cause red eyes. When the body is tired, the blood vessels in the eyes can become dilated, leading to redness and puffiness of the eyes.

This condition can be exacerbated by prolonged staring at a screen or performing tasks that require intense concentration.

Injury to the Eye

Injury to the eye, such as a scratch, can cause redness, pain, and discomfort. More severe injuries, such as a blow to the eye or a chemical burn, can also cause red eyes and require medical attention.

Exposure to Chemicals

Exposure to chemicals, such as chlorine or air pollution, can cause irritation and inflammation of the eyes, leading to redness and watering.

In some cases, exposure to chemicals can lead to more serious eye conditions, such as cataracts or corneal ulcers.

Conclusion

Red eyes can be caused by a myriad of reasons and it is important to determine the underlying cause of the redness in order to find the appropriate treatment.

If you experience redness, pain, or discomfort in your eyes, it is important to seek medical attention to determine the underlying cause and prevent further damage to your eyesight.