Red eyes are a common occurrence and can be caused by various factors. Understanding the underlying causes behind red eyes is crucial in reaching an accurate diagnosis and determining the appropriate treatment.

In this guide, we will explore the most common reasons why eyes become red and provide insights into the diagnostic process.

Allergies

Allergies are a leading cause of red eyes among individuals of all ages. When exposed to allergens such as pollen, pet dander, or dust mites, the eyes may become itchy, watery, and red.

This allergic response is the result of the immune system releasing histamines, which dilate the blood vessels in the eyes.

Conjunctivitis

Conjunctivitis, commonly known as pink eye, is another frequent cause of red eyes. This condition occurs when the conjunctiva, a thin and transparent membrane covering the surface of the eye, becomes inflamed.

Conjunctivitis can be caused by viral or bacterial infections, as well as by allergies or irritants such as smoke or chlorine.

Dry Eyes

Dry eyes occur when the tear production is insufficient or of poor quality. This can cause the eyes to become red, irritated, and sensitive to light.

Factors such as aging, hormonal changes, medications, and environmental conditions can contribute to dry eyes. Additionally, excessive screen time and prolonged contact lens wear may exacerbate the symptoms.

Wearing contact lenses for extended periods or improper care of lenses can lead to red eyes. The presence of a foreign object on the eye’s surface can cause irritation, inflammation, and redness.

Furthermore, using expired or poorly fitting contact lenses can increase the risk of eye infections, which may result in red eyes.

Corneal Ulcers

Corneal ulcers are open sores that develop on the cornea, the transparent front surface of the eye. They can be caused by bacterial or viral infections, trauma, or even wearing contact lenses for too long.

Corneal ulcers often cause redness, pain, and blurred vision, requiring immediate medical attention to prevent further complications.

Subconjunctival Hemorrhage

A subconjunctival hemorrhage refers to the bursting of a blood vessel located beneath the transparent conjunctiva. This condition can occur due to a sudden increase in blood pressure, excessive eye rubbing, or as a side effect of certain medications.

While it may look alarming, a subconjunctival hemorrhage typically resolves on its own within a week or two without any serious consequences.

Uveitis

Uveitis is the inflammation of the uvea, the middle layer of the eye that contains the iris, ciliary body, and choroid. In addition to redness, symptoms of uveitis may include eye pain, sensitivity to light, blurry vision, and floaters.

Uveitis can be caused by infections, autoimmune diseases, trauma, or certain medications, and prompt medical attention is required to prevent complications.

Glaucoma

Glaucoma is a group of eye disorders characterized by damage to the optic nerve, often accompanied by increased eye pressure.

While redness of the eyes is not always present in glaucoma, some individuals may experience redness due to the increased pressure. It is vital to diagnose and treat glaucoma early to prevent permanent vision loss.

Episcleritis

Episcleritis is the inflammation of the episclera, a thin layer between the conjunctiva and the white part of the eye. It typically causes localized redness and discomfort, but rarely affects vision.

The exact cause of episcleritis is often unknown, although it can occur in association with certain autoimmune diseases.

Iritis

Iritis, also known as anterior uveitis, is the inflammation of the iris, the colored part of the eye. It causes various symptoms including redness, eye pain, sensitivity to light, decreased vision, and pupil abnormalities.

Iritis can be idiopathic or associated with infections, autoimmune conditions, or trauma, and immediate medical attention is necessary to prevent complications.

Conclusion

Red eyes can be caused by a range of factors, from harmless allergies to potentially serious conditions such as glaucoma or corneal ulcers. Proper diagnosis and treatment are crucial in managing this symptom effectively.

If you experience persistent redness, pain, or changes in vision, it is important to consult an eye care professional for a thorough evaluation and appropriate care.