Common Eye Diseases: Symptoms, Treatment and Urgent Warning Signs
Blur, redness and irritation can have several causes. This overview explains what common eye conditions involve and how treatment differs; it cannot identify your diagnosis from a symptom list. Some important diseases cause little or no discomfort early on.
First: symptoms that should not wait
Seek urgent care for sudden loss of vision, flashes with a sudden increase in floaters, a dark curtain or shadow, severe eye pain, or a painful red eye with reduced vision. Contact-lens wearers with pain, light sensitivity or new blur should remove their lenses and contact an eye clinician promptly.
Conjunctivitis and dry eye
Conjunctivitis can cause redness, watering, discharge or itching. Viruses, bacteria, allergens and irritants can produce overlapping symptoms. Antibiotics do not treat viral conjunctivitis; mild bacterial cases do not always need them. Pain, marked light sensitivity or persistent reduced vision requires assessment rather than assuming ordinary pink eye.
Dry eye can cause grittiness, burning and fluctuating blur. Treatment may include lubricants, changes to airflow and screen habits, and management of eyelid or tear-film problems. Prescription anti-inflammatory treatment or punctal plugs are options for selected patients after examination. See dry-eye relief and safe eyelid care.
Cataracts
A cloudy natural lens can cause gradual blur, glare and difficulty with night vision. A revised prescription or lighting changes may help daily tasks temporarily, but glasses do not remove the cataract. Surgery replaces the lens when the expected benefit justifies the risks and the person’s visual needs warrant it; there is no requirement to wait until the cataract is “advanced.”
Glaucoma
Glaucoma damages the optic nerve and often has no noticed symptoms at first. It can occur even when pressure is within the usual range. Assessment may combine nerve examination, pressure measurements, visual fields and imaging. Treatment lowers pressure using drops, laser or surgery according to the type and findings; it cannot restore already lost nerve tissue. Sudden painful redness with blur, halos or nausea can be an emergency.
Age-related macular degeneration
AMD affects central vision and may cause wavy lines, missing detail or difficulty recognizing faces. New distortion needs prompt evaluation. Wet AMD is commonly treated with anti-VEGF injections. AREDS2 supplements are for selected disease stages and do not cure AMD. For geographic atrophy, specific injection treatments are approved in the United States; suitability, risks and local availability require a retina specialist’s advice. Avoid treating “dry AMD” as one uniform stage with one treatment.
Diabetic retinopathy
Diabetes can damage retinal vessels before the person notices visual change. Glucose and blood-pressure management and planned retinal review remain important. Depending on retinal findings, treatment may include injections for macular swelling or proliferative disease, laser, or surgery for complications. An injection is not simply reserved for a universal “advanced-stage” threshold.
Retinal tears and detachment
New flashes, numerous floaters or a spreading shadow require urgent retinal assessment. A small tear may be sealed with laser or freezing; a detachment may require surgery. A painless eye is not necessarily a safe eye, and symptoms cannot determine the required procedure.
Use the overview to prepare questions
- What diagnosis and stage were found in each eye?
- Which examination findings support that diagnosis?
- Is the goal symptom relief, preventing further loss, or improving vision?
- What follow-up is needed if symptoms remain unchanged?
For everyday prevention, see practical risk-reduction habits. For documenting symptoms, see a vision-change record.
Sources and review
Reviewed October 28, 2026. General education, not an individual diagnosis or treatment plan.