Dog Pink Eye: Conjunctivitis Causes and Care

By Tailwisp Editorial TeamUpdated October 17, 20263 min read

Red, goopy eyes are a common reason for vet visits, and the cause is not always obvious.

What it is

The conjunctiva is the thin pink tissue lining the inner eyelids and covering part of the eye. When it is inflamed, the eye looks red and swollen, and it may produce clear, yellow or green discharge. Conjunctivitis can affect one or both eyes.

Signs

• Redness of the white of the eye or eyelid lining
• Discharge: watery, mucus or pus-like
• Squinting or blinking
• Rubbing the face on the floor or with paws
• Swollen eyelids
• Crusting around the eye

Causes

• Allergies, often with itchy skin. See environmental allergies in dogs
• Bacterial or viral infection
• Irritants such as dust, smoke or shampoo
• Dry eye. See dry eye in dogs
• Eyelid or lash problems that rub the eye
• Foreign material such as grass seeds
• Other eye diseases that make the eye look red

Why an exam matters

Red eyes can signal serious problems such as glaucoma or corneal ulcers. See glaucoma in dogs and corneal ulcers in dogs. Using the wrong drops can make some of these worse. Your vet can examine the eye, use stain to check for ulcers and measure tear production and eye pressure.

Treatment

Treatment depends on the cause. Options include prescription eye drops or ointments, allergy management, treating dry eye or correcting eyelid problems. Give medication exactly as directed, and finish the course.

Safe home care

• Clean the area gently with a damp, clean cloth or a vet-approved eye wash. See how to clean dog eyes safely.
• Prevent rubbing with a cone if advised.
• Keep hair trimmed around the eyes. See how to trim hair around a dog's eyes.
• Avoid sprays and irritants.
• Wash your hands after treatment.

Do not use human products

Human eye drops, especially those with steroids, can cause harm if there is an ulcer. Never use leftover medication unless your vet says so.

Emergency signs

Go to the vet promptly for:

• Severe squinting or holding the eye shut
• A cloudy or blue eye
• A bulging or enlarged eye
• Sudden vision change
• Trauma to the eye
• Thick pus or heavy discharge

Allergies and seasonal flares

Dogs with itchy skin may also have itchy eyes. Managing allergies with your vet can reduce flare-ups. See dog skin allergies.

Prevention

1. Keep eyes clean and hair trimmed.
2. Protect from irritants and wind.
3. Do not let dogs hang their heads out of car windows.
4. Keep vaccinations current as advised.
5. Check eyes daily for early changes.

Common mistakes

• Waiting several days.
• Using human drops.
• Wiping with harsh products.
• Stopping medication early.

Troubleshooting

• The discharge keeps returning: ask about dry eye, allergies or eyelid problems.
• One eye only: look for foreign material or injury.
• My dog resists drops: ask for ointment or tips.

A simple plan

1. Book a vet exam.
2. Give medication as directed.
3. Prevent rubbing.
4. Review causes.

Real-life examples

A spaniel has red eyes with itchy skin, and allergy management helps. A terrier with a grass seed under the eyelid improves after removal. A pug with squinting turns out to have an ulcer and needs urgent treatment. The right diagnosis matters.

Protecting vision

Eyes are delicate, and early care often prevents lasting damage.

The takeaway

Red eyes need an exam, since causes vary. Avoid human drops and act fast if the eye looks painful or cloudy.

This article is general educational information, not veterinary advice. Every dog is different. If your dog is unwell, or you are unsure about a symptom, diet change or medication, contact your veterinarian.