Sudden Watery Eyes (Epiphora): Causes and When to See an Eye Doctor

Excessive tearing (epiphora) can stem from overproduction of tears or impaired drainage. Common causes include:

Overproduction (Reflex Tearing)

• Dry eye disease: Paradoxical reflex tearing from ocular surface irritation.
• Allergies: Seasonal (pollen) or perennial (dust mites, pet dander); itching, redness, swelling.
• Irritants: Smoke, wind, pollution, onions, chemicals.
• Ocular surface disease: Blepharitis, conjunctivitis, corneal abrasion/ulcer.
• Trichiasis/misdirected lashes: Rubbing the cornea.

Impaired Drainage

• Nasolacrimal duct obstruction (NLDO): Congenital (infants) or acquired (age-related stenosis, trauma, inflammation, tumors).
• Punctal stenosis or malposition: Eyelid laxity (ectropion) prevents pump mechanism.
• Canalicular blockage: From infections (chlamydia, herpes), medications (docetaxel), or trauma.

Systemic and Other Factors

• Thyroid eye disease: Proptosis, exposure, inflammation.
• Sjögren's syndrome: Aqueous deficiency → reflex tearing.
• Hormonal changes: Pregnancy, menopause, oral contraceptives.
• Medication side effects: Some antihypertensives, cholinergics, chemotherapy, eye drops (echothiophate).
• Emotional tearing: Normal psychogenic response.

When to See an Ophthalmologist

• Persistent (> few days) or worsening tearing
• Pain, vision changes, light sensitivity
• Redness, discharge, swelling
• History of trauma, surgery, radiation
• Associated systemic symptoms

Diagnosis involves slit-lamp exam, dye disappearance test, irrigation/probing, and possibly imaging. Treatment targets the underlying cause.