Green or yellow goop? Watery clear tears? Reddish-brown tear stains? White-gray thick gunk? Upload a photo — AI identifies the discharge color and ranks likely causes (bacterial infection, allergies, dry eye, porphyrin staining, foreign body). Triage urgency and step-by-step home care included.
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Take a close-up photo showing the eye discharge clearly. Include the eye corner where discharge accumulates. If both eyes are affected, photograph each separately. Natural daylight, no flash.

Our AI examines: discharge color (yellow, green, clear, brown, white-gray, black), consistency (watery vs thick), amount, whether one or both eyes, and associated signs (redness, swelling, squinting).

Receive a clear assessment: likely cause (bacterial infection, allergy, dry eye, porphyrin staining, etc.), urgency (ER / same-day vet / monitor at home), and step-by-step home care if appropriate. Plus whether you need prescription eye drops.
Eye discharge color is one of the clearest diagnostic signals in dog medicine. Each color points to specific causes and urgency levels. Here are the 7 main types our AI identifies — from normal "sleep dust" to serious infection requiring prescription drops. Also try our dog eye checker or dog skin checker or dog nose checker.
Small amounts of crusty material in the inner corner of the eye, especially on waking — this is NORMAL in most dogs. Appearance: small (pea-sized or less); gray, light tan, or slightly reddish-brown; wipes away easily with warm water; eye looks normal underneath (white not pink, no squinting); doesn't accumulate rapidly during the day. Cause: overnight, tears keep flowing but aren't blinked away, so mucus + dust + dead cells accumulate. It's the same "sleep dust" humans have. Breeds that typically have more morning discharge: brachycephalic (short-faced) breeds like Pugs, Bulldogs, Shih Tzus, Boston Terriers due to shallow eye sockets; long-faced breeds with loose eyelids like Bloodhounds and Saint Bernards. When it's NOT normal: large amounts (pen-cap sized or bigger), bright yellow or green, one eye only with redness, fresh discharge accumulating during the day, or sudden change in pattern. Regular morning cleaning with a warm damp cloth is good hygiene even for normal discharge.


Yellow or green eye discharge in dogs almost always means bacterial infection (conjunctivitis). It's the most common urgent eye discharge scenario. Appearance: thick, sticky, yellow to deep green; may dry into crusts; often heavy overnight accumulation; eye may be mildly red; can affect one or both eyes. Causes: primary bacterial conjunctivitis; secondary infection of allergic or viral conjunctivitis; corneal ulcer with infection (emergency); foreign body causing infection; dry eye becoming infected. Urgency: VET VISIT within 24-48 hours. Urgent same-day if combined with: squinting, severe redness, pawing at eye, recent trauma, puppy/senior dog, discharge increasing rapidly. Treatment: prescription antibiotic eye drops (most common: tobramycin, ofloxacin, or gentamicin eye drops 2-4 times daily for 7-10 days). Sometimes oral antibiotics if severe. Treatment cost: $80-150 vet visit + $20-40 drops. Untreated consequence: can progress to corneal ulceration and vision loss. Home supportive care while waiting: warm saline compresses 5 min 2-3x/day; gentle cleaning with warm water; e-collar to prevent rubbing; NO human OTC eye drops. Expected improvement: noticeable within 2-3 days of antibiotic drops; full resolution in 7-10 days.
Clear watery discharge ("tears") that's more than your dog's normal amount suggests allergies, foreign body, or tear duct issues. Appearance: clear, thin, watery; may be excessive tearing that runs down face; usually both eyes if allergy, one eye if foreign body; minimal crusting. Causes: ENVIRONMENTAL ALLERGIES (most common) — pollen, dust mites, mold, smoke; FOOD ALLERGIES — often combined with ear issues and paw licking; FOREIGN BODY — grass seed, eyelash, dust on cornea; usually one eye, may be combined with squinting; IRRITANT EXPOSURE — smoke, chemicals, strong perfumes; BLOCKED TEAR DUCT — tears overflow because can't drain normally. Urgency: vet within a few days if no improvement with basic care; same day if: one eye only with squinting (possible foreign body), or if discharge becomes yellow/green (secondary infection developing). Home care for allergies: identify and remove allergen if possible; clean 2-3x daily with warm saline; oral antihistamine like Benadryl (1 mg/lb) if vet approves; omega-3 supplement; air purifier; wipe paws and face after walks. Home care for suspected foreign body: DO NOT try to remove with tweezers — see vet, they have the tools to safely remove; flushing with saline may help if it's superficial. Most clear watery discharge resolves within 3-5 days with appropriate care.


Reddish-brown staining of fur under a dog's eyes is usually cosmetic, not a medical problem. Appearance: reddish-brown, rust-colored, or copper-colored fur below inner eye corner; fur itself is stained, not an active discharge flowing out; most visible in light-colored breeds. Cause: porphyrin — a normal iron-containing pigment in tears. When tears sit on light fur and are exposed to air, porphyrin oxidizes, creating the reddish-brown color. Contributing factors: tear overflow from shallow eye sockets or blocked tear ducts; hard water or tap water high in minerals; food allergies; yeast infections on wet fur under eyes; light-colored coat (dark fur hides the staining). Most affected breeds: Maltese, Bichon Frise, Shih Tzu, Poodle (Toy), Lhasa Apso, Havanese, Yorkshire Terrier, Cocker Spaniel, West Highland White Terrier, Pekingese. Management: daily cleaning with pet-safe tear stain wipes; switch to filtered or bottled water; probiotics for some dogs; stainless steel/ceramic bowls only; trim hair around eyes so fur stays drier; hypoallergenic diet if food allergy suspected; omega-3 supplement. Existing stained fur is PERMANENT — must grow out over 2-3 months. New fur grows in unstained if causes are addressed. AVOID: bleach, peroxide, human whitening products (damage eyes); any product with tylosin (illegal veterinary antibiotic misused for tear stains). A vet visit is appropriate if: tear staining developed suddenly in adulthood (possible blocked tear duct), is accompanied by eye redness or discharge, or if staining is severe despite addressing common causes.
Thick white or gray mucus-like discharge without much tearing suggests dry eye — known as keratoconjunctivitis sicca (KCS). Appearance: thick, mucus-like, white to grayish; sticky and hard to remove; eye may appear dull or lack typical wetness; lid margins may stick slightly; usually both eyes (though one eye can be worse); chronic — keeps coming back. Cause: insufficient tear production. The cornea compensates by producing thick mucus to protect itself. Why dry eye happens: immune-mediated attack on tear glands (most common); medications (sulfa-based drugs, atropine); distemper (rare); nerve damage; congenital in some breeds. Predisposed breeds: Cavalier King Charles Spaniel (very common!), Cocker Spaniel, Bulldog, Boston Terrier, Pug, Shih Tzu, West Highland White Terrier, Miniature Schnauzer. Diagnosis: Schirmer tear test by vet — simple, 60-second test that measures tear production. Treatment: LIFETIME management required; vet-prescribed cyclosporine (Optimmune) or tacrolimus eye drops to restore tear production (takes 4-8 weeks to see effect); artificial tears (Genteal, Systane) multiple times daily for comfort; sometimes short-course antibiotics if secondary infection. Critical: untreated dry eye progresses to corneal damage, pigmentation, and eventual vision loss. Once diagnosed, lifelong treatment is necessary. Response to cyclosporine is excellent in most dogs — tear production often returns to normal. If discharge is thick white-gray in your dog, especially in predisposed breeds, request a Schirmer tear test from your vet.


Discharge from ONLY ONE EYE is usually more urgent than both-eye discharge — it points to a specific problem with that eye rather than a systemic cause. Common causes: FOREIGN BODY — grass seed, eyelash, dust trapped in eye; often causes sudden-onset tearing and squinting; removing the foreign body resolves it. CORNEAL ULCER — scratch or injury to cornea; extremely painful; dog squints heavily; may have yellow-tinged discharge if infected; vet within 24 hours. TRAUMA — injury from rough play, branch, cat swat, etc.; painful; may have blood. EYELID ABNORMALITY — entropion (eyelid rolled inward rubbing cornea), distichiasis (extra lashes touching cornea); chronic one-eye issue; more common in specific breeds. BLOCKED TEAR DUCT (NASOLACRIMAL) — overflow tears from blocked drainage; usually minor issue, mostly cosmetic. CHERRY EYE — prolapsed third eyelid gland; visible red lump in inner corner of eye; common in Bulldogs, Beagles, Cocker Spaniels; surgical correction. UVEITIS — inflammation inside eye; painful; multiple possible causes. Urgency for one-eye discharge: SAME-DAY vet visit if combined with squinting, pain signs (pawing, whimpering, hiding), cloudy eye appearance, or sudden onset with any obvious discomfort. Within a week if mild and no pain. Don't leave a one-eye issue for "wait and see" — corneal ulcers can progress to perforation within days if untreated.
Black or very dark crusty material around a dog's eyes can have several causes. Most common: PORPHYRIN buildup over time — reddish-brown tears that have accumulated and darkened to near-black; same cosmetic cause as tear stains but heavier; wipes off eventually with consistent cleaning. OLD DRIED DISCHARGE — yellow or green discharge that's been there for days and dried dark; still indicates the underlying infection needs treatment. DUST AND ENVIRONMENTAL DEBRIS — accumulating on sticky discharge (especially in outdoor dogs); usually brushes away with warm cleaning. POST-INFECTIOUS STAINING — darkened area left after a resolved eye infection. RARE CAUSES worth checking: OCULAR MELANOMA — a dark mass or spot on or around the eye; usually raised, growing, possibly bleeding — needs veterinary evaluation; LENTIGO — benign dark pigmentation of the skin around the eye, common in older dogs; flat and stable over time; no action needed. When black discharge IS concerning: combined with raised dark mass or lump on or near the eye; growing or changing area of darkness; bleeding from dark area; combined with other eye symptoms (squinting, redness, swelling). If your dog has black-ish crusting with no other signs, start with consistent daily cleaning for 1-2 weeks and see if it resolves — if not, or if you see any dark mass, vet evaluation is appropriate.

Upload a photo now — AI identifies the discharge color, ranks likely causes (bacterial infection / allergies / dry eye / porphyrin / foreign body), and tells you urgency level. For one-eye discharge with squinting, sudden severe symptoms, or eye injury — skip the photo and see a vet today.
Check Dog Eye Discharge Now →PawCheck provides AI-generated preliminary health analysis for informational and educational purposes only. This service is not intended to replace professional veterinary advice, diagnosis, or treatment. The AI analysis has inherent limitations and may not always be accurate. Always seek the advice of a qualified, licensed veterinarian with any questions regarding your pet's health. Never disregard professional veterinary advice or delay in seeking it because of information provided by this tool. If your pet is experiencing a medical emergency, contact your veterinarian or emergency animal hospital immediately. By using this service, you acknowledge and agree to these terms.

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