Causes of Red Eye

What is Red Eye?

What is Red Eye

The disorder known as red eye causes the whites of the eyes to look red or reddish. The dilating of blood vessels in the eyes, which can happen for several reasons, can be a significant cause. Every age group can suffer from red eyes, frequently signs of a more severe condition. It can affect one or both eyes; additional symptoms like itchiness, burning, or discharge might also be present. Red eyes are often not serious, but they can indicate a more severe condition that needs medical care.

Determining the underlying reason for a red eye is crucial to choose the best course of action. Allergies, dry eyes, conjunctivitis (pink eye), infections, and eye traumas are common causes of red eyes. Depending on the underlying reason, Specialists use different therapies to cure red eyes, including eye drops, antibiotics, and in some extreme situations, surgery. If the red eye is accompanied by excruciating pain or vision problems, or if it doesn’t get better with home remedies, it’s crucial to consult a doctor. In this article, I will explain some common causes of red eye in detail leading to a logical conclusion.

What does a Red Eye look like and Feel Like?

Due to dilated blood vessels, a red eye often has a pinkish or reddish appearance. Depending on the condition’s underlying etiology, the level of redness can change. Additionally, the watch may occasionally appear swollen and have crusting or discharge around it. The affected eye may be light-sensitive and feel irritated, itchy, or even painful. Watery eyes, blurred vision, a gritty or sandy feeling in the eye, and the impression that something is lodged in the eye may also occur along with the redness of the eye. Sometimes a headache or sinus pain will also accompany red eyes. It’s crucial to visit an eye doctor for an evaluation and the right course of therapy if you have a red look along with any other symptoms.

Common Causes of Red Eye

Allergies, dry eyes, conjunctivitis or pink eye, and infections are typical reasons for red eyes. The use of contact lenses, exposure to chemicals, smoke, intense lighting, and other conditions can also result in redness. Red eyes may occasionally indicate a more serious underlying problem, such as corneal ulcers or dry eyes, so you should start treatment for them immediately. For an accurate diagnosis and course of therapy, it is crucial to comprehend the causes of red eyes. We will discuss the following common reasons for red eye in detail.


Eye allergies can cause swelling and redness, which can harm the eyes. When the immune system overreacts to allergens like pollen, pet dander, grass, or weeds, the result is an inflammation of the eye’s surface, which results in allergy eye symptoms. Red-eye typically results in redness, tears, and irritation in both eyes.

Dry Eyes

Bloodshot, itchy eyes can result from dry eyes. When your eyes do not produce enough tears to lubricate the eye(s) adequately or when your tears evaporate too quickly, dry eyes develop. Age, hormonal changes, some medications (like antihistamines), sleep aids, certain medical illnesses that result in dry eyes (such as Sjogren’s syndrome), and hormonal changes are just a few of the factors that can reduce the number of tears you produce. When you focus with your eyes for extended periods, such as reading or driving a long distance, your tears tend to dry up quickly. Other factors contributing to dry, tired eyes are sleep deprivation, spending too much time on digital devices, such as computers, smart phones, and TVs, lousy lighting, exposure to external factors including wind, smoke, or dry weather, wearing contacts for a prolonged time, and high intake of alcohol.

Contact Lens

The use of contact lenses may reduce the amount of oxygen reaching the eye. If you use extended-wear contacts or wear any form of communication for longer than advised, this is most likely an issue. Oxygen deprivation in the eye can lead to inflammation and infection, which may involve bacteria, viruses, fungi, or parasites. Microbial keratitis or a corneal ulcer, an open sore on the cornea’s surface, may occur from this.

Corneal Ulcers

Corneal ulcers are sores or ulcers that affect the cornea, the outside layer of the eye. A different name for this illness is keratitis. Numerous factors might lead to corneal ulcers, which include sleeping in contact lenses, bacteria, viruses including herpes simplex and varicella-zoster viruses, fungi acanthamoeba, which is a type of parasite, using well water to clean contacts, swimming or showering with them on, or scratching, cutting, or burning the cornea, and diseases affecting the closure of the eyelids, such as bell’s palsy. If you have signs of a corneal ulcer, seeking quick medical assistance is critical. This illness can harm your vision permanently if you do not get treatment early.


Conjunctivitis is an inflammation of the conjunctiva, a membrane that covers the white part of your eye and the inside of your eyelids. Another name for this ailment is pink eye. The whites of your eyes appear pink or crimson when the conjunctiva is inflamed. Other signs and symptoms of conjunctivitis include a hot, itchy sensation, excessive tears, a sensation like something is in your eye, and discharge of mucus or pus, which may result in the eyelid or lash crusting. Viral or bacterial conjunctivitis is highly infectious. Therefore, it is very contagious from one person to another.


Eyelid inflammation is also known as blepharitis. Various reasons, like multiple conditions, such as ocular rosacea, bacterial or fungal infections, or an allergic reaction to Demodex mites found in eyelashes, can cause this. Blepharitis symptoms include red, itchy, and flaky eyelids at the lash line.


Inflammation on the sclera’s surface, just below the conjunctiva, is known as episcleritis. Episcleritis may affect one eye, both eyes or a tiny portion of one eye. Episcleritis might be uncomfortable, although it usually doesn’t hurt too much. It can be challenging to distinguish between episcleritis and scleritis, a deeper sclera-specific inflammation, without a medical evaluation.

Eyelid Stye

A stye is an inflammation-causing obstruction of the meibomian gland in the eye. Your upper or lower eyelid’s outer or inside may be affected. If you have a stye, the edge of your eyelid may turn red, bloated, and painful. Due to the clogged gland, the affected area may fill with meibum and eventually develop to the size of a pea.


The bulge further back on the eyelid, known as a chalazion, is frequently brought on by a hordeolum that has partially scarred and developed into a cyst. A chalazion can initially be uncomfortable and red, but it is typically not very painful.


Injury is another crucial cause of red eye. It mostly happens due to irritation or bleeding. Other reasons could be any object getting in your eye, an accident, or chemical exposure. The symptoms of injury include pain in a watch, swelling inside or on the surrounding area of an eye, difficulty in moving your eye, decreased vision, and sometimes different pupil sizes.

Subconjunctival hemorrhage

A little blood collection between the conjunctiva and the sclera, the white part of the eye, is known as a subconjunctival hemorrhage. It happens when tiny blood vessels rupture and leak into that restricted area. Subconjunctival hemorrhages, fortunately, don’t hurt and go away in a couple of weeks. They may be brought on by damage or trauma to the eyes, rubbing their eyes, tensing, forceful sneezing or coughing, and medicines like blood thinners.


In conclusion, various diseases, ranging from minor irritants to significant medical issues, can result in red eye. It is critical to understand the underlying cause to choose the best course of action for the red eye. Allergies, dry eyes, conjunctivitis, infections, and eye injuries are typical causes of red eyes. Red eyes can signal a more serious underlying illness that needs immediate medical care.

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