By Dial A Vet Veterinary Team
Conjunctivitis means the conjunctiva (the moist pink membrane lining the eyelids and covering part of the white of the eye) is inflamed. Owners see redness, squinting, pawing, and discharge. It is a clinical sign with many causes, from dust and allergies to dry eye, infection, or a hidden corneal ulcer. Eye problems escalate quickly, so home watching has limits.
Key takeaways
- Red, watery, or sticky eyes with squinting deserve a vet check, especially if only one eye is affected.
- Never use leftover human eye drops unless your vet directs a specific product.
- Dry eye, entropion, foreign bodies, and ulcers can mimic simple "pink eye."
- Both eyes involved more often suggests allergy or systemic irritation; one eye raises concern for injury or foreign material.
- Sudden pain, cloudiness, or vision loss is urgent.
Signs to look for
- Red or swollen conjunctiva
- Clear, yellow, or green discharge
- Squinting or frequent blinking
- Pawing or rubbing the face
- Swollen eyelids or third eyelid more visible
- Light sensitivity
Related eye topics: dry eye, cherry eye, glaucoma, and excessive tearing.
Common causes
- Allergies and environmental irritants (dust, smoke, pollen)
- Bacterial or viral infection
- Dry eye (keratoconjunctivitis sicca)
- Eyelid conformation problems (entropion, ectopic cilia)
- Foreign bodies (grass seeds are notorious in Australia)
- Corneal ulcers secondary to trauma
- Tear duct blockage
- Chemical irritation from shampoos or sprays
When it is an emergency
Seek urgent care if your dog:
- Cannot open the eye or seems in severe pain
- Has a cloudy blue or white cornea
- Has a bulging eye or very dilated pupil with pain
- Has thick yellow-green discharge with fever or lethargy
- Suddenly bumps into objects or loses vision
- Had known trauma, chemical splash, or a grass seed hunt in the eye area
What not to do
- Do not dab tea tree oil, essential oils, or antiseptics near the eye
- Do not share drops between pets
- Do not ignore a "just watery" eye that worsens over a day
- Do not use red-vein human drops from the pharmacy cupboard
How vets diagnose and treat
Your vet will examine eyelids, tear production, fluorescein stain for ulcers, and intraocular pressure when indicated. Treatment may include saline flushes, prescription antibiotic or anti-inflammatory eye medicines, tear stimulants for dry eye, or surgery for eyelid defects. Grass seeds may need removal under local or general anaesthesia. We do not list drug doses here.
Home support while arranging care
- Prevent rubbing with an Elizabethan collar if advised
- Wipe discharge gently with clean, moistened gauze (separate for each eye)
- Note whether one or both eyes are involved and take clear photos in daylight
- Keep walks out of long grass if seeds are suspected
Grass seeds and Australian seasons
In warmer months, grass seeds (awns) lodge under eyelids and cause sudden unilateral pain and discharge. Spaniels and dogs with floppy ears and feathering are frequent patients. If your dog suddenly squints after a field walk, treat it as urgent rather than waiting on allergy drops. Early seed removal prevents corneal ulcers and deeper migration.
Allergy seasons versus infection
Bilateral watery eyes with sneezing in spring may suggest allergy, yet infection and dry eye still need ruling out when redness is significant. Unilateral mucoid discharge with pain leans infectious, foreign body, or ulcer until proven otherwise. Over-the-counter rinses without a diagnosis waste time when an ulcer is brewing. Ask for fluorescein staining whenever pain is present.
Follow-up and finishing the course
Finish prescribed eye medicines on schedule even when the eye looks clearer on day two. Stopping early is a common reason redness returns. Book the recheck if your vet wants stain repeated, especially after ulcers. Bring the bottles so staff can confirm what was used and how often.
FAQ
Can conjunctivitis spread to my family?
Most canine conjunctivitis causes are not a major human risk, but wash hands and seek advice if anyone develops eye redness after contact.
Will it clear without treatment?
Mild irritant cases sometimes settle, but ulcers and dry eye will not. Examination is safer than waiting when pain or discharge is present.
Are certain breeds prone?
Yes. Bulldogs, Pugs, Spaniels, and other breeds with eyelid or tear film issues need extra vigilance.
How fast should medicine work?
Many infectious or irritant cases improve within a few days of correct therapy. Worsening needs reassessment.
Talk with a vet
If your dog's eye is red, sticky, or painful, a Dial A Vet veterinarian can review photos and help you decide how quickly to seek hands-on care. Book a Dial A Vet consult.
References
- Merck Veterinary Manual: Conjunctivitis in dogs
- RSPCA Australia: Eye care and when to seek help
- American College of Veterinary Ophthalmologists: Client education on red eye
Disclaimer: Educational only. This page does not replace an examination or advice from your own veterinarian. If you are worried about your pet right now, contact your local vet or nearest emergency animal hospital.
