Red eyes, a common and often harmless condition, occur when the tiny blood vessels on the surface of the eye become dilated or inflamed. While usually not a cause for major concern, understanding the underlying causes and associated symptoms can help you determine when to seek professional medical attention.
20 Common Causes of Red Eyes
- Conjunctivitis (Pink Eye): This is a highly contagious infection of the conjunctiva, the thin, clear membrane covering the white part of the eye and the inner surface of the eyelids.
- Allergies: Allergens like pollen, dust mites, and pet dander can trigger an allergic reaction, leading to itchy, watery, and red eyes.
- Dry Eye Syndrome: Reduced tear production or poor tear quality can irritate the eyes, causing redness, dryness, and a burning sensation.
- Eye Strain: Prolonged computer use, reading, or driving can strain the eyes, leading to redness, fatigue, and blurred vision.
- Foreign Body: Dust, dirt, or other particles can irritate the eye, causing redness, discomfort, and a feeling of something being in the eye.
- Corneal Abrasion: A scratch on the cornea, the clear dome-shaped surface of the eye, can cause significant pain, redness, and sensitivity to light.
- Uveitis: Inflammation of the uvea, the middle layer of the eye, can cause redness, pain, blurred vision, and sensitivity to light.
- Glaucoma: This condition involves increased pressure within the eye, which can damage the optic nerve. Symptoms may include redness, halos around lights, and gradual vision loss.
- Subconjunctival Hemorrhage: This harmless condition occurs when a small blood vessel under the conjunctiva bursts, causing a bright red patch on the white of the eye.
- Blepharitis: Inflammation of the eyelids can cause redness, itching, crusting, and flaking of the eyelids.
- Contact Lens Irritation: Improper contact lens wear or care can irritate the eyes, leading to redness, discomfort, and increased risk of infection.
- Eyelid Stye: A localized infection of an oil gland in the eyelid can cause a painful red bump.
- Chemical Exposure: Exposure to irritants like chlorine, smoke, or certain chemicals can cause redness, irritation, and tearing.
- Eye Injury: Blunt trauma or penetrating injuries to the eye can cause severe redness, pain, and vision problems.
- Certain Medications: Some medications, such as antihistamines and decongestants, can have side effects that include dry eyes and redness.
- Autoimmune Diseases: Conditions like rheumatoid arthritis and lupus can affect the eyes, causing inflammation and redness.
- Viral Infections: Certain viral infections, such as herpes simplex virus, can cause eye infections and redness.
- Exposure to Wind or Sun: Prolonged exposure to wind or sun can dry out the eyes and cause irritation.
- Smoking: Smoking can irritate the eyes and increase the risk of developing eye problems.
- Alcohol Consumption: Excessive alcohol consumption can dehydrate the body and lead to dry eyes and redness.
Associated Symptoms
- Pain: Eye pain can range from mild discomfort to severe, throbbing pain.
- Itching: Itching is a common symptom of allergies and certain types of conjunctivitis.
- Tearing: Excessive tearing can occur due to irritation, allergies, or blocked tear ducts.
- Discharge: Discharge from the eyes can be watery, thick, or pus-like, depending on the underlying cause.
- Sensitivity to Light: Sensitivity to light, also known as photophobia, can be a symptom of various eye conditions.
- Blurred Vision: Blurred vision can occur with certain eye infections, injuries, and underlying medical conditions.
- Headache: Headaches can sometimes be associated with eye strain or certain eye conditions.
Complications
While most cases of red eyes resolve without complications, some conditions can lead to more serious problems if left untreated. These can include:
- Vision Loss: Untreated glaucoma, uveitis, and certain infections can lead to permanent vision loss.
- Corneal Scarring: Corneal abrasions and certain infections can cause scarring on the cornea, which can affect vision.
- Eye Infections: Untreated eye infections can spread to other parts of the eye or even to the brain.
When to See a Doctor
Seek immediate medical attention if you experience:
- Severe eye pain
- Sudden vision loss
- Sensitivity to light
- Discharge that is yellow, green, or bloody
- A foreign body embedded in the eye
- Trauma to the eye
Prevention Tips
- Practice good hand hygiene: Wash your hands frequently, especially before touching your eyes.
- Avoid touching your eyes: Rubbing your eyes can spread infection and irritate the eyes.
- Protect your eyes from the sun: Wear sunglasses that block both UVA and UVB rays.
- Use artificial tears: If you have dry eyes, use artificial tears to lubricate your eyes.
- Take breaks from computer screens: Look away from the screen every 20 minutes and focus on a distant object for 20 seconds.
- Remove contact lenses before bed: Sleeping in contact lenses can increase the risk of eye infections.
- Quit smoking: Smoking can irritate the eyes and increase the risk of eye problems.