If you’re typing “why are my eyes…” into a search engine, something about your eyes looks or feels off. Maybe they’re red, dry, twitchy, puffy, watery, or discolored. Most eye changes have straightforward explanations rooted in everyday habits, environment, or minor conditions. Some, though, signal something that needs prompt attention. Here’s a breakdown of the most common eye complaints and what’s behind them.
Why Are My Eyes Red?
Redness is the single most common eye complaint, and it has a wide range of causes. The most frequent is conjunctivitis, or pink eye. Viral conjunctivitis typically causes mild discomfort with a watery discharge and a gritty feeling, while bacterial conjunctivitis produces thicker, yellowish discharge and eyes that are glued shut when you wake up. Allergic conjunctivitis is distinct: both eyes are affected, there’s intense itching, and the discharge tends to be watery or stringy.
Dry eye is another major cause of redness. It creates a foreign-body sensation, as if something is stuck in your eye, along with intermittent watering as your eyes try to compensate. Blepharitis, an inflammation of the eyelids, causes redness that’s worst in the morning with crusty, itchy lids. A subconjunctival hemorrhage, which looks alarming (a bright red patch on the white of your eye), is usually painless and harmless, often caused by straining, sneezing, or rubbing your eyes.
More serious causes of red eyes include keratitis (corneal inflammation), which brings pain, light sensitivity, and blurred vision. Iritis causes a deep, constant ache that radiates into your brow or temple, and it develops over hours. Acute angle-closure glaucoma produces sudden, severe throbbing pain with halos around lights, and it requires emergency treatment.
Why Are My Eyes Dry?
Your tear film has three layers: an outer oil layer, a middle water layer, and an inner mucus layer. Dry eye happens when any of these layers is disrupted. The most common culprit is meibomian gland dysfunction, where the tiny oil glands lining your eyelids become blocked and can’t release enough oil to keep tears from evaporating too quickly.
Screen time is a major trigger. You blink significantly less when staring at a screen, which means your tear film breaks down faster. Wind, dry indoor air, allergies, and contact lens wear all compound the problem. Managing dry eyes often starts with practical changes: taking regular breaks from screens, avoiding direct airflow from fans or vents, and using preservative-free artificial tears. For persistent dryness, warm compresses can help unclog blocked oil glands.
Why Are My Eyes Twitching?
A twitching eyelid, called myokymia, is almost always benign. The most common triggers are sleep deprivation, too much caffeine, stress, nicotine use, and dry eyes. Severe fatigue or physical overexertion can also set it off. These twitches usually affect one eye at a time, come and go on their own, and resolve once you address the trigger.
The twitching becomes worth investigating if it spreads from your eyelid to other parts of your face, persists for weeks, or is accompanied by other neurological symptoms. In rare cases, eyelid twitching can progress to blepharospasm (involuntary eye closure) or hemifacial spasm, or it can be linked to nervous system conditions like multiple sclerosis, nerve injuries, or tumors.
Why Are My Eyes Puffy?
Puffiness around the eyes happens when fluid builds up in the thin tissue surrounding them. The skin here is thinner than almost anywhere else on your body, so even small amounts of fluid retention are visible.
The most common lifestyle triggers include:
- High salt intake, which causes your body to hold onto extra water
- Alcohol, which leads to dehydration and rebound fluid retention
- Too little or too much sleep, both of which disrupt fluid balance
- Crying, which irritates the eyes and causes temporary swelling
- Allergies, which inflame the tiny blood vessels around the eyes
Aging also plays a role. As you get older, your body loses water more readily throughout the day, and the tissues around your eyes naturally weaken, making puffiness more pronounced. Smoking can worsen the problem by disrupting hormones involved in fluid balance.
Why Are My Eyes Watery?
Watery eyes happen for two reasons: either you’re producing too many tears, or tears aren’t draining properly. Your tears normally flow from the glands above your eye, across the surface, and drain through tiny ducts in the inner corner of your eyelids into your nose. When those drainage channels become blocked, tears have nowhere to go.
Overproduction of tears is the body’s reflex response to irritation. Allergies, blepharitis, corneal scratches, smoke, wind, and infections like pink eye or sinus infections all trigger excessive tearing. Entropion, a condition where the eyelid turns inward so the lashes rub against the eye, is another common cause. If your eyes water constantly without an obvious irritant, a blocked tear duct may be the issue, which is more common as you age.
Why Are My Eyes Yellow?
Yellowing of the whites of your eyes is caused by a buildup of bilirubin in the blood, a yellow pigment produced when your body breaks down old red blood cells. Normally, your liver processes bilirubin and sends it into your bile ducts for elimination. When that process breaks down at any step, bilirubin accumulates and deposits in the skin and eyes.
The most common causes are hepatitis, alcohol-related liver disease, gallstones blocking the bile ducts, and toxic reactions to medications or supplements. Less commonly, conditions that destroy red blood cells faster than the liver can process them will cause yellowing. Wilson disease, a rare disorder where copper accumulates in the liver, is another possibility. Yellow eyes are always worth getting checked because they indicate something is wrong with your liver, gallbladder, or blood cells.
Why Do I Have Dark Circles?
Dark circles under the eyes are primarily a vascular and structural issue, not just a sign of being tired. The skin beneath your eyes is thin and translucent, which means the network of blood vessels underneath shows through easily. When those vessels dilate, the area looks blue or purple. Stretching the skin makes the discoloration more obvious.
Aging deepens dark circles through several mechanisms. The hollows beneath your eyes (tear troughs) become more pronounced as you lose bone density, subcutaneous fat, and collagen in the area. The skin loses elasticity, and the cheeks begin to sag, exaggerating the shadow effect along the orbital rim. Genetics play a large role in how visible your blood vessels are and how much pigment your skin produces around the eyes.
What a White Ring Around Your Iris Means
A grayish-white arc or ring around the edge of your cornea is called arcus senilis. It’s caused by lipid (fat) deposits in the peripheral cornea and appears in over 70% of people over age 60. At that age, it’s considered a normal part of aging, likely caused by increased permeability of blood vessels near the cornea that allows cholesterol-carrying particles to pass through.
In younger people, the same ring is called arcus juvenilis and can signal high cholesterol or a genetic lipid disorder. It’s particularly common in people with familial hypercholesterolemia. Lab findings associated with the ring include elevated triglycerides, total cholesterol, and LDL. If you’re under 50 and notice this ring, a lipid panel is a reasonable next step. For older adults, no testing is typically needed.
Symptoms That Need Urgent Attention
Most eye changes are benign, but a few patterns point to emergencies. Sudden, painless vision loss in one eye, especially if it feels like a curtain being drawn across your field of vision, suggests a retinal detachment, which is a surgical emergency. A sudden burst of new floaters or flashing lights in your vision can be an early warning sign of the same problem.
Sudden, temporary vision loss in one eye that resolves on its own (called amaurosis fugax) can indicate a blood flow problem and possible stroke risk. If you’re over 60 and experience vision loss with a new headache, scalp tenderness, or jaw pain while chewing, giant cell arteritis is a concern that requires immediate treatment to prevent permanent vision loss in the other eye.
Severe eye pain with a red eye, nausea, vomiting, and halos around lights points to acute angle-closure glaucoma. A steamy or hazy-looking cornea and a pupil that doesn’t react to light are additional signs. Vision loss that develops over several days, especially with pain during eye movement and washed-out color vision, can indicate optic neuritis. Any of these patterns warrants same-day evaluation.