Bacterial Eye Infections: What to Watch For and What to Do

Red, sticky, or painful eyes aren’t always just irritation. Bacterial eye infections can start mild and get serious fast, especially for contact lens users. This page explains common signs, simple first steps, how doctors treat them, and ways to avoid getting them in the first place.

Common types include bacterial conjunctivitis (pink eye), keratitis (cornea infection), blepharitis (eyelid infection), and orbital cellulitis (deep tissue infection). Typical symptoms are redness, yellow or green discharge, eye pain, crusting on lashes, light sensitivity, blurred vision, and eyelid swelling. If you have any drop in vision or sharp pain, treat it like an emergency.

How infections start and who’s at risk

Bacteria get into the eye when the surface is injured or contaminated. Risk factors include wearing contact lenses overnight, using expired or shared eye makeup, touching eyes with dirty hands, or having an existing skin or sinus infection. Kids pick up infections easily at daycare or school because they touch their faces and share towels or toys.

Contact lens wearers should be cautious: Pseudomonas and other aggressive bacteria can cause corneal ulcers if lenses are worn while sleeping or not cleaned properly. Those ulcers threaten vision and often need stronger, urgent treatment.

Diagnosis and common treatments

A doctor will examine your eye, check vision, and may use a slit lamp. For severe cases they take a swab to identify the bacteria. Mild bacterial conjunctivitis often clears with topical antibiotic drops or ointment such as erythromycin ointment, polymyxin B/trimethoprim, or topical aminoglycosides. Corneal infections usually need stronger drops like fluoroquinolones and closer follow-up. Orbital cellulitis or systemic spread may require oral or IV antibiotics.

Never put steroid drops in an infected eye unless a specialist prescribes them — steroids can hide symptoms and let bacteria worsen. Always finish the full course of prescribed antibiotics, even when symptoms improve.

Antibiotic resistance is real. If you don’t improve in 48–72 hours on drops, call your doctor. They may change the medication or run tests to find the right drug.

Simple home care and prevention

Do these things right away: stop wearing contact lenses until cleared, throw away old makeup, wash hands before touching eyes, and use a clean cloth or cotton to wipe discharge. Warm compresses help loosen crusts. Don’t share towels, pillows, or eye products.

For prevention: follow lens-care rules, replace lenses and cases as recommended, avoid sleeping in contacts, and toss mascara every three months. If buying meds online, use a trusted pharmacy and a valid prescription. If you experience worsening pain, vision loss, intense light sensitivity, or fever, seek urgent care. Quick action protects your vision and keeps a small infection from becoming a big problem.