Conjunctivitis (pink eye)

What it is

The conjunctiva is a thin transparent membrane over the sclera and inner lids. When inflamed it looks pink or red and may produce discharge or watering. Conjunctivitis is extremely common and usually settles without sight loss, but some causes need prompt assessment.

Three main types

Read the dedicated page for each type:

• Viral conjunctivitis — watery red eye, often after a cold; very contagious; antibiotics do not help
• Bacterial conjunctivitis — sticky yellow-green discharge, lids glued on waking; may need antibiotic drops
• Allergic conjunctivitis — intense itch in both eyes with hay-fever symptoms; antihistamine drops help

How to tell types apart

Itch dominant in both eyes suggests allergy. Thick pus and glued lids suggest bacterial. Watery redness after a cold suggests viral. Pain, reduced vision, contact-lens wear or a single very red painful eye are not typical of simple conjunctivitis — seek same-day assessment.

Self-care for mild cases

Cool compresses soothe irritation. Lubricating drops wash allergens or discharge. Wash hands often, avoid rubbing, do not share towels, and stop contact lenses until an eye professional says it is safe. Discard old eye makeup after infection.

Contagion and return to work

Viral pink eye spreads easily for days to two weeks. Bacterial disease often improves faster once antibiotic drops start. Follow school, childcare and workplace policies. Healthcare workers may need clearance before returning to patient care.

When to seek urgent care

Same-day assessment for moderate or severe pain, marked light sensitivity, reduced vision, newborn red eyes, contact-lens-related redness, injury, or if symptoms worsen after 48 hours of expected treatment.