Eye Symptoms — When to Worry.

Floaters and flashes

Floaters are tiny clumps in the vitreous gel of your eye that cast shadows on the retina. Almost everyone has some. They become more noticeable with age as the vitreous shrinks and pulls away from the retina (posterior vitreous detachment) — a normal process that usually doesn't cause harm.

The red flags: a sudden shower of new floaters, flashes of light (like camera flashes in your peripheral vision), or a dark curtain or shadow coming across your vision. Any of these can signal a retinal tear or detachment — a true emergency. Get to an eye doctor or emergency department the same day.

Red eyes

Most red eyes are benign — minor irritation, allergies, mild conjunctivitis, dry eye, or a broken blood vessel on the surface (subconjunctival hemorrhage) that looks scary and resolves on its own.

See a doctor promptly if redness comes with significant pain, light sensitivity, blurred vision, discharge that's thick or yellow-green, or if you wear contacts. Contact-lens-related red eyes need urgent evaluation — corneal infections can move fast.

Eye pain

Eye pain has many possible causes — corneal abrasion, dry eye, foreign body, infection, inflammation, sinus pressure, migraine, or angle-closure glaucoma. Severe sudden pain combined with blurred vision, halos around lights, nausea, and a red eye can indicate acute angle-closure glaucoma, which is an emergency.

In general, real eye pain (as opposed to mild irritation or burning) deserves an evaluation rather than waiting it out.

Eye twitching

Eyelid twitching — what doctors call myokymia — is almost always benign. It's typically triggered by stress, sleep deprivation, caffeine, alcohol, or eye strain. Most cases resolve within days to weeks once those factors improve.

See a doctor if twitching persists for several weeks, involves more than just the eyelid, makes the lid close fully, or comes with other neurological symptoms (drooping, weakness, facial twitching).

Sudden vision loss

Sudden loss of vision in one eye is always a medical emergency — vascular causes (retinal artery or vein occlusion), retinal detachment, optic neuritis, and stroke can all present this way, and some have a narrow window for effective treatment. Go to an emergency department, not a clinic.

Headaches and vision

Eye strain headaches usually feel like dull pressure behind the eyes or across the brow after extended close work. They typically respond to breaks, an updated prescription, or treatment of underlying dry eye.

Migraines can cause visual auras — shimmering, zigzag lines, or temporary blind spots — usually lasting 10 to 60 minutes and followed by a headache. New or different headache patterns, especially in adults over 50 or with neurological symptoms, deserve evaluation.

When to call versus when to go

Call your eye doctor today for: contact lens-related red eye, new persistent floaters, foreign body sensation that doesn't resolve, or any sudden change in vision.

Go to the ER for: sudden vision loss, a curtain across your vision, severe eye pain with nausea, eye trauma with bleeding or vision change, or any chemical splash.