Moon Blindness in Horses: Equine Recurrent Uveitis Signs and Treatment

By Dr Duncan Houston

Moon blindness is one of the most important eye diseases horse owners need to recognise early.

The proper name is equine recurrent uveitis, often shortened to ERU. It is a recurring or persistent inflammatory disease inside the horse’s eye. A horse may have one painful flare, improve with treatment, then flare again weeks, months, or years later. Each episode can leave damage behind.

That is the real danger. ERU is not just “a sore eye”. It can lead to cataracts, glaucoma, retinal damage, chronic pain, loss of the eye, and blindness. ERU is widely recognised as one of the leading causes of blindness in horses, and there is currently no true cure. (Center for Equine Health)

If your horse is squinting, tearing, sensitive to light, has a cloudy or blue-looking eye, or has repeated eye flare-ups, do not treat it like simple conjunctivitis. A painful horse eye needs veterinary assessment because ERU, corneal ulcers, glaucoma, trauma, and foreign bodies can look similar from the outside but need very different treatment.

Quick Answer

Moon blindness, or equine recurrent uveitis, is a chronic inflammatory eye disease in horses that causes repeated or persistent inflammation inside the eye. Signs may include squinting, tearing, light sensitivity, redness, a cloudy or blue cornea, a small pupil, and recurring painful eye episodes. ERU is serious because repeated inflammation can permanently damage the eye and may eventually cause cataracts, glaucoma, retinal damage, chronic pain, and blindness. (Center for Equine Health)

What Is Moon Blindness in Horses?

Moon blindness is the older name for equine recurrent uveitis.

The term came from the historic belief that flare-ups were linked to phases of the moon. We now know that is not the cause. ERU is a complex immune mediated disease influenced by genetic, environmental, infectious, and inflammatory factors. (MSD Veterinary Manual)

Uveitis means inflammation of the uvea, the middle layer of the eye. The uvea includes important structures such as the iris, ciliary body, and choroid. These structures help control the pupil, internal eye fluid dynamics, blood supply, and eye function.

In ERU, inflammation either returns repeatedly or persists at a low level. Some horses have dramatic painful flares. Others have a quieter, more insidious form where damage develops slowly with fewer obvious signs.

That subtle form is dangerous because the horse may not look severely painful every day, but the eye can still be deteriorating.

Why Is ERU So Serious?

ERU is serious because every flare can add damage.

The eye does not always return to normal after each episode. Repeated inflammation can cause structural changes that affect comfort and vision.

Possible complication	Why it matters
Cataracts	Clouding of the lens can reduce or block vision
Posterior synechiae	The iris can stick to the lens, affecting pupil function
Glaucoma	Increased eye pressure can cause pain and vision loss
Retinal degeneration or detachment	Can severely affect vision
Lens luxation	The lens can shift from its normal position
Corneal oedema	The eye may look blue, cloudy, or hazy
Phthisis bulbi	A chronically diseased eye may shrink
Chronic pain	A blind or damaged eye can still be painful
Blindness	The final outcome in many severe or poorly controlled cases

MSD Veterinary Manual lists chronic ERU complications including cataracts, lens luxation, glaucoma, phthisis bulbi, and retinal degeneration. UC Davis also reports that cumulative ERU damage can lead to cataracts, glaucoma, and blindness. (Center for Equine Health)

The key clinical point is this: the painful flare today matters, but the long-term pattern matters even more.

What Causes Equine Recurrent Uveitis?

There is usually no single simple cause.

ERU is best understood as a complex immune mediated disease. After an initial episode of uveitis, the horse’s immune system may continue to react against tissues inside the eye, causing repeated or persistent inflammation. (MSD Veterinary Manual)

Possible contributors include:

Factor	How it may contribute
Immune mediated inflammation	The immune system attacks or reacts against eye tissue
Previous acute uveitis	A first episode may increase future ERU risk
Leptospira exposure	Associated with ERU in some horses and regions
Ocular trauma	May trigger inflammation in susceptible horses
Genetics	Important in Appaloosas and some other breeds
Environment	Wet climates and contaminated water sources may increase exposure risks
Chronic low-grade inflammation	May slowly damage the eye without obvious flares

Leptospira species have been associated with ERU, and MSD notes that serum, aqueous humor, and vitreous can be tested in selected cases. However, not every horse with ERU has Leptospira driven disease, and not every horse exposed to Leptospira develops ERU. (MSD Veterinary Manual)

That distinction matters. ERU is not always a simple infection that can be cured with one antibiotic course. It is a chronic inflammatory eye disease that needs proper diagnosis, monitoring, and a long-term plan.

Which Horses Are Most at Risk?

Any horse can develop ERU, but some horses are higher risk.

Risk factor	Why it matters
Appaloosa breed	Higher risk of uveitis and ERU-associated blindness
Leopard complex spotting	Associated with increased risk in Appaloosas
Warmbloods	Reported risk for some forms, including posterior ERU
Draft breeds	May be seen with insidious forms in some reports
Previous uveitis episode	Future recurrence remains possible
Wet environments or standing water	May increase Leptospira exposure in some regions
Chronic or repeated eye signs	Raises suspicion for ERU
One or both eyes affected	ERU can be unilateral or bilateral

UC Davis reports that Appaloosas are 8 times more likely to develop ERU than other studied breeds, and the LP genetic test can help evaluate ERU risk in Appaloosas. The University of Minnesota also reports that Appaloosas are 8.3 times more likely to develop uveitis and four times more likely to go blind as a result of ERU. (Center for Equine Health)

This does not mean every watery-eyed Appaloosa has ERU. It does mean recurrent or subtle eye signs in an Appaloosa deserve a lower threshold for veterinary examination.

What Are the Signs of Moon Blindness?

ERU signs vary depending on whether the horse is in an acute flare, between flares, or developing chronic disease.

Common signs include:

Sign	What you may notice
Squinting	The horse partly closes the eye due to pain
Excessive tearing	Wet cheek, clear discharge, or tear staining
Light sensitivity	Horse avoids bright light or keeps the eye closed
Cloudy or blue-looking cornea	Corneal oedema or inflammation
Redness	Bloodshot appearance around the eye
Small pupil	Common during uveitis
Eye discharge	Usually watery, but may vary
Head shyness	Pain or irritation around the eye
Recurrent episodes	Signs improve, then return later
Vision changes	Spooking, bumping, hesitation, or loss of confidence
Chronic eye changes	Cataract, misshapen pupil, scarring, or enlarged painful eye

MSD describes active ERU signs including tearing, blepharospasm, corneal oedema, episcleral congestion, aqueous flare, and fibrin in the anterior chamber. (MSD Veterinary Manual)

The owner-facing clue is recurrence. A one-off painful eye may be acute uveitis, trauma, ulceration, or another eye disease. Repeated episodes raise concern for ERU.

The Three Main Patterns of ERU

ERU does not look identical in every horse.

UC Davis describes three broad syndromes: classic, insidious, and posterior ERU. (Center for Equine Health)

ERU pattern	What it looks like	Why it matters
Classic ERU	Painful flare-ups separated by quieter periods	Repeated attacks can gradually reduce vision
Insidious ERU	Persistent low-grade inflammation with fewer obvious painful episodes	Can be missed until significant damage has occurred
Posterior ERU	Inflammation affects the back of the eye, including vitreous, retina, or choroid	Vision loss may occur even when surface signs are less obvious

The insidious form is the one owners can miss most easily. The horse may not be dramatically squinting, but the eye can still be accumulating damage.

How Worried Should You Be?

Risk level	What it looks like	What it may mean	What to do
Low concern	Mild watery eyes, both eyes affected, horse comfortable, no cloudiness, no squinting	Dust, wind, flies, mild irritation	Monitor closely, improve environment, call if persistent
Moderate concern	One eye watery, mild redness, mild light sensitivity, previous eye history	Early uveitis, conjunctivitis, blocked duct, irritation, early ulcer	Book a veterinary examination soon
High concern	Squinting, eye partly closed, cloudy or blue cornea, small pupil, repeated flare-ups	ERU, corneal ulcer, trauma, foreign body, glaucoma	Call your vet promptly
Critical	Eye held shut, severe cloudiness, sudden vision change, enlarged eye, blood, severe swelling, rapidly worsening signs	Sight-threatening eye disease, deep ulcer, severe uveitis, glaucoma, trauma	Treat as urgent veterinary care

The biggest decision point is pain. A squinting horse eye is urgent until proven otherwise.

What Else Can Look Like Moon Blindness?

ERU can mimic other eye diseases. Other eye diseases can also trigger uveitis-like signs.

That is why guessing is dangerous.

Condition	Why it can look similar
Corneal ulcer	Causes tearing, squinting, cloudiness, and pain
Foreign body	Hay, grass, or debris under the eyelid can cause sudden pain
Traumatic uveitis	Injury can cause internal eye inflammation
Glaucoma	Can cause pain, cloudiness, tearing, and vision loss
Conjunctivitis	Causes redness and discharge, but usually less deep pain
Stromal abscess	Can cause corneal opacity and pain
Infectious keratitis	Can cause discharge, pain, and corneal damage
Cataract	Can be confused with other cloudy eye changes
Squamous cell carcinoma	Eyelid or ocular masses may cause irritation
Retinal disease	May cause vision change without obvious surface signs

The most important rule-out is a corneal ulcer. The treatment path can be completely different.

MSD states that primary corneal disease can share signs with ERU and that a thorough ophthalmic examination and fluorescein stain are essential to differentiate them. (MSD Veterinary Manual)

This is why ERU is not a “just put drops in it” condition. The wrong drop at the wrong time can make a horse’s eye worse.

Why You Should Not Use Old Eye Medication

This is one of the most important safety points in the whole article.

Do not restart old steroid eye drops, human eye drops, leftover ointment, or previous ERU medication unless your vet has examined the eye and confirmed it is appropriate.

Why?

Because today’s painful eye may not be the same problem as last time.

A horse with ERU can also develop a corneal ulcer, glaucoma, a foreign body, trauma, or infection. Steroids may be useful for some uveitis cases, but they can be dangerous if a corneal ulcer is present.

The practical rule: do not use steroid eye medication until the cornea has been checked.

How Do Vets Diagnose ERU?

Diagnosis is based on history, recurrence, clinical signs, and a full eye examination.

A vet may assess:

Diagnostic step	Why it matters
History of previous episodes	ERU is recurrent or persistent by definition
Full ophthalmic exam	Assesses eyelids, cornea, pupil, lens, retina, and internal structures
Fluorescein staining	Checks for corneal ulcers before certain medications are used
Tonometry	Measures eye pressure to assess glaucoma or pressure changes
Slit lamp examination	Helps identify aqueous flare, fibrin, synechiae, and cataracts
Fundic examination	Assesses the retina and posterior eye where possible
Ocular ultrasound	Useful when cloudiness blocks the view into the eye
Blood or ocular fluid testing	May be considered for Leptospira or other causes
Referral to an ophthalmologist	Important for complex, chronic, or surgical cases

UC Davis states that ERU diagnosis involves clinical and ophthalmic examination plus a history of recurrent or persistent inflammation, and that fluorescein stain may be used to assess the cornea and distinguish other ocular diseases. AAEP notes that if two or more uveitis episodes are observed, a diagnosis of ERU can be made. (Center for Equine Health)

A single episode of uveitis is not always ERU. The pattern over time matters.

What Do Vets Look For Inside the Eye?

During an ERU flare, vets are not just looking for redness.

They are looking for evidence of internal inflammation and previous damage.

Finding	Why it matters
Aqueous flare	Protein and inflammatory cells in the front chamber of the eye
Miosis	A small pupil, often seen with uveitis
Corneal oedema	Blue or cloudy appearance
Fibrin	More severe inflammatory material inside the eye
Posterior synechiae	Iris adhesions to the lens
Cataract	Lens damage from repeated inflammation
Vitreous haze	Inflammatory change in the back of the eye
Retinal degeneration or detachment	Serious vision concern
Low intraocular pressure	Can occur with active uveitis
High intraocular pressure	Suggests glaucoma risk

These are not things an owner can reliably assess from the stable doorway. Photos help, but they do not replace an eye exam.

How Is an Acute ERU Flare Treated?

Treatment focuses on reducing inflammation, relieving pain, protecting vision, and preventing further damage.

Common treatment categories include:

Treatment type	Purpose
Topical corticosteroids	Reduce intraocular inflammation when safe
Topical nonsteroidal anti-inflammatory medication	May help control inflammation in selected cases
Atropine	Dilates the pupil and reduces painful internal muscle spasm
Systemic NSAIDs	Help reduce pain and inflammation
Systemic corticosteroids	Used in selected cases when appropriate
Antimicrobials	Used when infection is suspected or confirmed
Rechecks	Monitor response, cornea, eye pressure, and complications

MSD lists topical corticosteroids, topical atropine, systemic NSAIDs, suprachoroidal cyclosporine implants, and vitrectomy among ERU management options. The primary treatment goals are to reduce inflammation, relieve discomfort, and prevent vision loss. (MSD Veterinary Manual)

Treatment must be tailored to the individual horse. The presence of a corneal ulcer, glaucoma, infection, pregnancy, systemic illness, medication tolerance, and performance withdrawal considerations can all affect the plan.

Why Rechecks Matter

Rechecks are not just about seeing whether the eye looks less red.

A vet may need to reassess:

Recheck question	Why it matters
Is pain improving?	Pain control is a welfare issue
Is inflammation truly reducing?	Persistent inflammation causes damage
Is the cornea still intact?	Ulcers change the treatment plan
Is eye pressure normal?	Glaucoma can develop or worsen
Is the pupil responding?	Pupil changes help assess disease activity
Can medication be tapered?	Stopping suddenly may allow rebound inflammation
Is referral needed?	Chronic ERU may need specialist options
Is the other eye affected?	ERU can be unilateral or bilateral

The eye may look better before the deeper inflammation is fully controlled. That is why treatment tapering should be guided by a vet.

Long-Term Management of ERU

There is currently no true cure for ERU, so long-term management is about control.

The goals are to reduce flare frequency, protect comfort, preserve vision where possible, and recognise when the eye is becoming painful or blind.

Long-term management may include:

Strategy	Why it helps
Fast treatment of every flare	Reduces cumulative damage
Regular ophthalmic examinations	Detects recurrence or chronic changes
Flare diary	Tracks timing, severity, affected eye, and response
Environmental management	Reduces trauma, dust, and irritation
UV and fly protection	Supports comfort and reduces surface irritation
Leptospira investigation where relevant	May guide management in selected regions
Specialist referral	Opens options such as implants, injections, or vitrectomy
Monitoring the other eye	ERU can affect one or both eyes

ACVO notes that when ERU is caught early, multiple treatment options may prolong vision and comfort for affected horses. (ACVO Public)

The practical mindset is not “fix it once and forget it”. ERU is a condition that needs a plan.

Advanced Treatment Options

Some horses need more than repeated topical medication.

Suprachoroidal Cyclosporine Implant

A cyclosporine implant is a specialist surgical option that releases immunomodulatory medication inside the eye over time. It may reduce recurrence in selected horses, especially when the eye still has useful vision and is structurally suitable.

MSD lists suprachoroidal cyclosporine implants as a management option for ERU, and ACVO also describes cyclosporine implants as a surgical treatment option. (MSD Veterinary Manual)

This is not for every horse. Timing, existing eye damage, vision status, cost, access to an ophthalmologist, and risk profile all matter.

Vitrectomy

Vitrectomy is another specialist surgical option. It involves removing the vitreous, which may contain inflammatory material or infectious triggers in selected cases.

MSD lists vitrectomy as a treatment option that may decrease uveitic episodes in ERU. (MSD Veterinary Manual)

This may be more relevant for certain forms of ERU and should be discussed with an equine ophthalmologist.

Intravitreal Gentamicin

Low-dose intravitreal gentamicin is a specialist treatment option used in selected ERU cases. ACVO lists low-dose intravitreal gentamicin injection among surgical treatment options for ERU. (ACVO Public)

This is not standard “antibiotic treatment” in the simple sense. It is a specialist ocular procedure and must be selected carefully based on the horse’s diagnosis, eye status, and ophthalmology assessment.

Enucleation

Enucleation means removal of the eye.

That sounds confronting, but it can be the kindest option when the eye is blind and painful. Preserving a blind, painful eye is not always preserving welfare.

MSD lists enucleation for blind, painful eyes affected by ERU. (MSD Veterinary Manual)

Many horses adapt well to one-eyed vision when pain is removed and the remaining eye is healthy.

Appaloosas and Moon Blindness

Appaloosas deserve special attention.

ERU in Appaloosas may be more common, more subtle, more likely to affect both eyes, and more likely to lead to blindness than in many other horses. UC Davis describes Appaloosas as particularly susceptible and notes that the LP allele associated with white spotting is an ERU risk factor, especially in homozygous horses. (Center for Equine Health)

For Appaloosa owners, the practical plan is:

Recommendation	Why it matters
Establish a baseline eye exam	Helps detect future changes
Monitor subtle tearing or cloudiness	Insidious ERU may not look dramatic
Discuss genetic risk where relevant	LP testing can help evaluate risk
Act early with any flare	Delay increases cumulative damage risk
Consider earlier ophthalmology referral	Advanced options may preserve comfort and vision

A small watery eye in a high-risk horse deserves more respect than it often gets.

When Is This an Emergency?

Call a vet urgently if your horse has:

Red flag	Why it matters
Squinting or eye held closed	Usually indicates pain
Sudden severe tearing	Can occur with ulcers, trauma, uveitis, or foreign bodies
Blue, white, grey, or cloudy cornea	May indicate corneal oedema, ulceration, infection, or internal inflammation
Light sensitivity	Common with painful uveitis
Small or irregular pupil	Can indicate internal inflammation or adhesions
Enlarged or bulging eye	Possible glaucoma
Blood in or around the eye	Trauma or severe inflammation
Sudden vision change	Needs prompt assessment
Repeated flare-ups	Raises suspicion for ERU
Worsening despite medication	Disease may be progressing or treatment may be inappropriate

MSD describes ERU as a condition requiring thorough eye examination, fluorescein staining, tonometry, and differentiation from corneal disease because treatment differs significantly. (MSD Veterinary Manual)

A simple rule: if the eye is painful, cloudy, or recurring, do not wait.

What Should You Do Right Now?

If your horse has a watery, squinting, cloudy, or painful eye:

1. Call your vet

Describe which eye is affected, when signs started, whether the horse is squinting, whether the eye is cloudy, and whether this has happened before.

2. Do not apply old eye medication

This is especially important for steroid-containing drops or ointments. The eye needs to be checked first.

3. Reduce bright light

If your horse is light-sensitive, shade may improve comfort while you arrange veterinary care.

4. Prevent rubbing

Rubbing can worsen ulcers, trauma, and inflammation. A safe protective mask or controlled environment may be needed.

5. Take clear photos

Photograph both eyes from the front and side in good light. Include close-ups of the pupil, cornea, eyelids, and any discharge.

6. Record the pattern

Write down the date, time, affected eye, signs, severity, treatment used, and response. This helps identify recurrence.

7. Ask about rechecks

Do not stop treatment just because the eye looks slightly better. ERU often needs careful tapering and follow-up.

Common Mistakes Owners Make

Mistake 1: Calling it conjunctivitis

A red watery eye is not a diagnosis. ERU, ulcers, glaucoma, foreign bodies, and trauma can all look similar early.

Mistake 2: Waiting because the horse is still eating

A horse with a painful eye may still eat. Appetite does not rule out serious eye disease.

Mistake 3: Restarting old steroid drops

Steroids may be appropriate for some ERU cases, but dangerous if a corneal ulcer is present.

Mistake 4: Stopping treatment too early

The eye may look calmer before inflammation is fully controlled.

Mistake 5: Missing subtle recurrence

A little extra tearing, mild cloudiness, or slight light sensitivity may be the beginning of another flare.

Mistake 6: Not tracking episodes

If episodes are not recorded, it is harder to recognise recurrence and diagnose ERU.

Mistake 7: Avoiding referral until the eye is blind

Advanced options are usually more useful when there is still vision to preserve.

Can Moon Blindness Be Prevented?

You cannot prevent every case of ERU, but you can reduce risk, detect flares earlier, and improve long-term management.

Step	Why it helps
Check eyes daily	Early changes are easier to treat
Use UV-protective fly masks where appropriate	Reduces light irritation and surface trauma risk
Manage flies and dust	Reduces conjunctival irritation and rubbing
Reduce trauma risks	Remove sharp branches, hooks, rough feeders, and unsafe fencing
Control rodents and standing water where practical	May reduce Leptospira exposure in some environments
Keep a flare diary	Helps identify recurrence patterns
Schedule regular eye checks for at-risk horses	Especially important for Appaloosas and horses with previous uveitis
Seek referral for recurrent cases	Gives access to specialist treatment options
Follow taper instructions carefully	Reduces rebound inflammation risk

For high-risk horses, prevention is less about guaranteeing ERU never happens and more about catching changes before they become irreversible.

Will My Horse Go Blind?

Some horses with ERU maintain useful vision for years with careful management. Others progress despite treatment.

The outcome depends on:

Factor	Why it matters
How early ERU is diagnosed	Early control reduces cumulative damage
Frequency of flares	More flares usually mean more risk
Severity of inflammation	Severe episodes can damage the eye quickly
Whether glaucoma develops	Major risk for pain and vision loss
Whether cataracts develop	Can significantly reduce vision
Whether the retina is affected	Posterior disease can be serious
Response to treatment	Some horses are easier to control than others
Access to specialist care	Advanced treatment may help selected cases
Owner compliance	Medication frequency and rechecks matter

UC Davis reports that ERU affects 2 to 25 percent of horses globally, with 56 percent of affected horses eventually becoming blind, and that more than 60 percent of affected horses are unable to return to previous levels of work. (Center for Equine Health)

That sounds frightening, but it is exactly why early action matters. You cannot control every outcome, but you can control how quickly the eye is examined and how carefully flare-ups are managed.

Normal Eye Irritation vs Possible ERU

More reassuring	More concerning
Both eyes mildly watery in wind or dust	One eye repeatedly waters or becomes painful
Eye is open and comfortable	Horse squints or holds the eye closed
No cloudiness	Blue, white, grey, or cloudy cornea
Signs settle quickly	Signs return repeatedly
No light sensitivity	Horse avoids light or keeps eye shut
No pupil change	Pupil looks small, irregular, or abnormal
No vision change	Horse bumps, hesitates, or becomes unusually spooky

The difference is not always obvious from the outside. When in doubt, the safest path is an eye exam.

Myth vs Reality

Myth	Reality
“Moon blindness is caused by the moon.”	The name is historical. ERU is a complex immune mediated eye disease.
“If the eye stops squinting, it is fixed.”	Pain may improve before inflammation is fully controlled.
“All watery horse eyes are conjunctivitis.”	Ulcers, uveitis, glaucoma, trauma, and foreign bodies can look similar.
“I can use the same drops as last time.”	The eye needs reassessment because the cause may be different this time.
“Only Appaloosas get ERU.”	Appaloosas are high risk, but any horse can develop ERU.
“A blind eye should always be kept.”	A blind painful eye may be best treated with enucleation for welfare.

FAQs About Moon Blindness in Horses

Is moon blindness painful?

Yes. Active uveitis is usually painful. Horses may squint, tear, avoid light, hold the eye partly closed, or become head-shy.

Can moon blindness be cured?

There is currently no true cure for ERU. Treatment aims to control inflammation, reduce pain, preserve vision, and reduce future flare-ups. (Center for Equine Health)

How do I know if my horse has ERU or a corneal ulcer?

You cannot reliably tell from appearance alone. Both can cause tearing, squinting, cloudiness, and pain. A vet may use fluorescein stain, tonometry, and a full ophthalmic exam to separate ERU from ulcers, glaucoma, and other eye problems.

Are Appaloosas more likely to get moon blindness?

Yes. Appaloosas are higher risk for ERU and ERU-associated blindness. Leopard complex patterning is also relevant to risk assessment in the breed. (Center for Equine Health)

When should I call the vet?

Call promptly if your horse is squinting, tearing from one eye, light-sensitive, cloudy-eyed, has a small pupil, seems visually abnormal, or has repeated eye flare-ups. A painful or cloudy horse eye should be treated as urgent.

The Bottom Line

Moon blindness is not just an old-fashioned name for a watery eye. It is a serious recurring or persistent inflammatory disease inside the horse’s eye.

The signs can look deceptively simple: squinting, tearing, cloudiness, light sensitivity, redness, or a small pupil. But the consequences can be long term. Repeated inflammation can cause cataracts, glaucoma, retinal damage, chronic pain, and blindness.

The safest rule is simple: if your horse has a painful, cloudy, or recurring eye problem, call your vet and do not start old medication without an exam. Early diagnosis, correct treatment, careful rechecks, and long-term monitoring give your horse the best chance of staying comfortable and sighted.

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If you are unsure whether your horse’s eye signs are mild irritation, a corneal ulcer, moon blindness, glaucoma, or an emergency, ASK A VET™ can help you understand what signs matter and when veterinary care is needed.