Eye discharge in one eye: what to know

A blocked tear duct, a particle, eyelid inflammation, or an infection can affect one eye first. Conjunctivitis may start on one side and later affect the other. Allergy often affects both eyes, but exposure or rubbing can make irritation feel uneven. One-sided discharge does not by itself identify the cause, so note its colour, thickness, timing, and accompanying symptoms.

Wash your hands before cleaning and after touching the affected eye. Use a clean, damp cloth to loosen discharge, wiping outward without rubbing. Keep the cloth, towel, pillowcase, cosmetics, and eye drops separate from other people’s items. Avoid contact lenses and eye makeup until symptoms settle. Do not cover the eye tightly, scrape the surface, or use leftover prescription drops.

Get urgent help for severe pain, sudden blurred or reduced vision, marked light sensitivity, an injury, chemical exposure, or swelling around the eye with fever. Seek prompt advice if a contact-lens wearer has one-sided redness or pain, if discharge is thick or worsening, or if symptoms do not start settling. A clinician can examine the eye and choose treatment safely.

Ask whether the tear duct, eyelid, cornea, or conjunctiva is involved, how long to avoid lenses, and how to prevent transfer to the other eye.