# Bloodshot Eyes in Dogs: Causes and Hyphema Care A red eye in a dog is a physical finding, not a diagnosis. The redness may come from dilated superficial vessels on the white of the eye, a condition called conjunctival hyperemia, or from blood that has pooled inside the front chamber of the eye, which is hyphema. These two problems look similar to an owner at arm's length and behave very differently. Conjunctival hyperemia often responds to simple topical therapy. Hyphema in dogs is a sign of underlying disease, and it can be the first visible evidence of a bleeding disorder, systemic hypertension, a retinal tear, or cancer inside the eye. The single most useful thing an owner can do is decide whether the redness sits on the surface or inside the eye, then get a veterinarian to measure blood pressure and run a clotting and platelet assessment. This guide separates the two conditions, explains the anatomy behind each, lists the causes that matter most in dogs, and describes how veterinarians work up and treat a bleeding eye. It also covers the red flags that mean the eye is in danger within hours, not days. **This article is educational and is not a substitute for veterinary diagnosis or treatment.** ## At a Glance: Surface Redness Versus Blood Inside the Eye | Feature | Conjunctival hyperemia | Hyphema | |--|--|--| | Location of redness | Vessels on the conjunctiva, the pink membrane over the sclera | Blood inside the anterior chamber, behind the cornea | | Appearance | Fine branching red lines that follow the surface | A pool of dark red fluid, often settling at the bottom of the eye | | Blanching test | Vessels narrow and pale with a topical vasoconstrictor such as phenylephrine | No change, the blood stays where it is | | Vision | Usually preserved | Often reduced, especially with a full chamber of blood | | Pain | Variable, often mild | Often marked, with squinting and light sensitivity | | Most likely causes | Allergy, irritant, dry eye, conjunctivitis, early corneal disease | Trauma, coagulopathy, systemic hypertension, retinal disease, neoplasia, immune-mediated disease | | First tests | Schirmer tear test, fluorescein stain, exam with magnification | Blood pressure, platelet count, coagulation panel, ocular ultrasound | | Urgency | Usually same-week | Same-day emergency | The blanching distinction is the core of the physical exam. Phenylephrine constricts the small vessels of the conjunctiva, so hyperemic tissue turns pale. Blood that has leaked into the anterior chamber is trapped and cannot be squeezed away. ## Understanding the Anatomy of a Red Eye The visible white of a dog's eye is the sclera, covered by a thin transparent layer called the conjunctiva. That conjunctiva carries a dense network of small blood vessels. When those vessels dilate, the eye looks bloodshot. This is conjunctival hyperemia, and it is a normal vascular response to irritation, infection, allergy, or dryness. Behind the cornea sits the anterior chamber, a fluid-filled space that holds aqueous humor. The iris and the lens form its back wall. Blood should never be in this chamber. When red blood cells leak from iris vessels, ciliary body vessels, or the vessels of the retina and optic nerve, they enter the aqueous humor and produce hyphema. Because blood is denser than aqueous humor, it settles. A small bleed may appear as a thin crescent at the bottom of the chamber. A large bleed can fill the chamber and hide the iris completely. The distinction matters because the two spaces have different blood supplies and different disease implications. Conjunctival vessels are exposed to the outside world and react to surface problems. The vessels that feed the iris and retina sit behind a blood-aqueous barrier, a tight junction system that normally keeps blood cells out of the eye. When that barrier breaks, the cause is usually inside the body, not on the surface. Hyphema also raises intraocular pressure in many dogs. Blood and clot can physically block the drainage angle where aqueous humor exits the eye. When drainage fails, pressure climbs and the optic nerve is damaged. In a large case series of 99 dogs with hyphema, 31.4 percent of eyes were diagnosed with glaucoma, and elevated intraocular pressure at the first exam multiplied the odds of blindness by more than nine times [1]. That is why a bleeding eye is treated as an emergency even when the dog still seems comfortable. ## Why Bloodshot Eyes in Dogs Get Noticed Owners usually spot a red eye during routine contact. The dog may look up at a certain angle, or the light catches the eye in a way that shows the color change. Some dogs rub the eye, squint, or avoid bright rooms. Others show no discomfort at all, which can be misleading. A dog with hyphema sometimes has no outward sign beyond the color. The blood may be painless at first. This is one reason hyphema is dangerous. An owner may decide to watch it for a few days, during which pressure rises or a retinal detachment progresses. Any dog with a red eye that does not blink normally, holds the eye closed, or has a cloudy cornea needs same-day care. Any dog with visible blood inside the eye needs same-day care as well. ## Conjunctival Hyperemia: The Surface Problem Conjunctival hyperemia is the most common reason a dog's eye looks bloodshot. The vessels are responding to something on or near the surface. Common triggers include environmental allergens such as pollen and dust, irritants such as smoke or shampoo, bacterial or viral conjunctivitis, dry eye from poor tear production, and early corneal injury. A foreign body under the third eyelid or a misplaced eyelash can also cause persistent redness. The clinical picture is usually mild. The eye may water. There may be a small amount of discharge. The dog often remains visual and only mildly uncomfortable. Veterinarians confirm the surface nature of the problem with a few quick tests. A Schirmer tear test measures tear production. A fluorescein stain checks for corneal ulcers and foreign bodies. A close exam with magnification looks at the conjunctiva, the third eyelid, and the eyelid margins. Because the vessels are superficial, a topical vasoconstrictor such as phenylephrine will blanch them. This is a useful bedside test when the diagnosis is unclear, and it separates hyperemia from hyphema in seconds. Treatment depends on the cause. Allergic conjunctivitis may settle with removal of the trigger and supportive care. Bacterial conjunctivitis may need topical antibiotics. Dry eye needs tear replacement and sometimes medication to stimulate tear production. A corneal ulcer needs specific therapy and, critically, a review of which topical drugs are safe. ## Hyphema in Dogs: Blood Inside the Eye Hyphema is blood in the anterior chamber of the eye. It is a sign, not a diagnosis. The blood itself is not the disease. The disease is whatever broke the vessels or prevented clotting. The appearance is distinctive once an owner knows what to look for. Blood settles with gravity, so a small bleed forms a crescent at the bottom of the chamber. A moderate bleed creates a fluid line across the eye. A complete hyphema fills the chamber and turns the whole eye dark red or black. The cornea may look hazy because blood and inflammatory cells cloud the aqueous humor. In a referral population of 99 dogs with hyphema, the causes broke down as follows: 36.4 percent systemic, 32.9 percent local ocular disease, 26.1 percent trauma, and 4.5 percent idiopathic [1]. That distribution is the single most important fact for an owner to understand. Roughly a third of dogs with blood in the eye have a body-wide problem, and another third have a serious eye disease. Only a minority have a simple explanation. Hyphema is often painful. The dog may squint, avoid light, and resist having the eye touched. The eye may be cloudy. The pupil may be small. Intraocular pressure may be high, normal, or low depending on the stage and cause. The prognosis is guarded. In the same series, 55.4 percent of eyes were blind at the final recheck, and the rate of vision loss ranged from 11.1 percent to 100 percent depending on the cause [1]. Causes with the worst outcomes were ocular neoplasia, chronic uveitis, and trauma. Enucleation was performed or recommended in 39.5 percent of eyes [1]. ## Causes of Hyphema in Dogs The causes fall into four broad groups: trauma, bleeding disorders, systemic vascular disease, and local eye disease. Each group has a different workup and a different prognosis. ### Trauma Trauma is a leading cause of hyphema in dogs. Sports ball injuries are a well-documented mechanism. In a study of 18 dogs with projectile ocular trauma, closed-globe injuries presented with traumatic uveitis in 91 percent of eyes and hyphema in 45 percent [2]. Small dense balls such as golf balls and baseballs caused the most damage. Open-globe injuries, which include corneal lacerations and scleral ruptures, required enucleation in five of six dogs [2]. Porcupine quills are another traumatic cause. A review of 17 globes with ocular quilling injuries found hyphema among the histologic findings, along with retinal detachment, cataract, and severe inflammation [3]. The time from the quilling event to the appearance of eye signs can be weeks to years, which makes the history easy to miss [3]. Snakebite is a less common but severe traumatic cause. In dogs with ocular and periocular snakebites requiring enucleation, common clinical signs included facial edema, corneal ulceration, uveitis, hyphema, and secondary glaucoma, and all eyes had lost vision before surgery [4]. A separate series of 11 dogs with snakebite found conjunctival hyperemia in every case and hyphema in one [5]. ### Coagulopathies and Platelet Disorders A bleeding disorder can present with hyphema as the first sign. A hereditary defect of platelet procoagulant activity, sometimes called Scott syndrome, causes epistaxis, hyphema, intramuscular hematoma, and prolonged bleeding after surgery in affected dogs [6]. Platelet count, platelet morphology, bleeding time, and routine clotting tests can all be normal in this condition, which means a standard panel may miss it [6]. Thrombocytopenia from any cause can also produce hyphema. A 5-year-old Pomeranian with B-cell chronic lymphocytic leukemia presented with anterior uveitis, hyphema, and secondary glaucoma in one eye, along with retinal hemorrhage in the other. Blood work showed a high lymphocyte count, anemia, and low platelets [7]. This case shows how a blood cancer can announce itself through the eye. ### Systemic Hypertension High blood pressure damages the small vessels of the eye, kidney, and heart. The eye is especially vulnerable because its vessels are fine and fragile. Systemic hypertension should be measured in any dog with retinal detachment, retinal hemorrhage, or hyphema [8]. A dog with a phenylpropanolamine overdose developed severe hypertension along with hyphema and retinal detachment in both eyes. Blood pressure control resolved the ocular changes within a month [9]. That case is a clean demonstration of the mechanism: raise the pressure, break the vessels, control the pressure, and the eye recovers. ### Retinal Disease and Detachment Blood in the anterior chamber can originate from the retina at the back of the eye. A study of 17 dogs with hyphema of presumed retinal origin found retinal detachments in 10 of 13 dogs evaluated by ultrasound and 5 of 6 globes evaluated histologically [10]. Routine blood work did not identify an underlying cause in any of those dogs [10]. The mean age was 11.5 years, and the prognosis for vision was poor. Ten dogs developed secondary glaucoma, and all dogs eventually lost vision [10]. This pattern is important for owners of older dogs. A geriatric dog with hyphema and no history of trauma may have a retinal problem that cannot be seen without ultrasound, because blood blocks the view of the back of the eye. ### Neoplasia Cancer inside the eye can bleed. Ocular neoplasia was one of the causes with the worst visual outcomes in the 99-dog series [1]. Iris tumors are a recognized source of intraocular hemorrhage. In a case series of sector iridectomy for pigmented iridal tumors, hyphema and fibrin clot formation occurred in all five operated eyes, and two eyes needed intracameral tissue plasminogen activator injections within two weeks of surgery [11]. That study describes surgical bleeding, but it also confirms how readily iris tissue bleeds when it is abnormal. Canine ocular gliovascular syndrome is a distinct entity in which a neovascular membrane grows from the optic nerve head or retina. In a study of 37 eyes, most dogs presented with hyphema and secondary glaucoma, with an average intraocular pressure of 39 mmHg. The average time to enucleation or evisceration was 27 days [12]. Labrador Retrievers had a relative risk 9.3 times higher than other breeds in that database [12]. ### Immune-Mediated and Infectious Disease Immune-mediated disease and infection can inflame the uveal tract and cause bleeding. Brucella canis is a documented cause. A 2-year-old spayed female mixed-breed dog had an eight-month history of recurrent bilateral anterior uveitis and hyphema from B. canis infection. Topical prednisone and atropine had failed. The inflammation resolved only after systemic antibiotics were added, and the ocular infection appeared to be eliminated [13]. [Ehrlichia canis](/knowledge/bacteria/pet-bacteria/ehrlichia-canis), the agent of [canine monocytic ehrlichiosis](/knowledge/bacteria/pet-bacteria/ehrlichia-canis-monocytic-ehrlichiosis-dogs-tick-thrombocytopenia), is another infectious cause. In a retrospective study of 46 affected dogs, 17 had ocular signs, and 5 of those 17 had ocular bleeding disorders including hyphema or retinal hemorrhage [14]. Exudative retinal detachment was the most common ocular finding [14]. ## Causes Table With Species Notes The table below lists the major causes of hyphema and red eye, with notes on how dogs and cats differ. Cats with hyphema are more likely to have systemic hypertension and lymphoma than dogs, while dogs more often present with trauma and primary ocular disease. Blood pressure measurement is essential in both species. | Cause category | Examples | Dog notes | Cat notes | |--|--|--|--| | Trauma | Projectile injury, quill, snakebite, blunt force | Common. Sports balls and quills are well documented [3][2][4] | Less commonly reported in the same literature, but blunt trauma occurs | | Coagulopathy | Platelet procoagulant defect, thrombocytopenia | Hereditary platelet defect reported in dogs [6] | Rodenticide and clotting factor disorders are common feline causes | | Systemic hypertension | Renal disease, endocrine disease, drug reaction | Documented with retinal detachment and hyphema [8][9] | More often the primary driver of hyphema and retinal hemorrhage | | Retinal disease | Retinal detachment, retinal vascular disease | Common in geriatric dogs, poor visual prognosis [10] | Retinal detachment from hypertension is a leading cause | | Neoplasia | Iris melanoma, ocular gliovascular syndrome, lymphoma | Ocular neoplasia has a poor visual outcome [12][1] | Lymphoma is a more frequent cause of feline intraocular bleeding | | Immune-mediated | Uveitis, Brucella canis | Documented with recurrent uveitis and hyphema [13] | Immune-mediated uveitis occurs but lymphoma must be excluded | | Infectious | Ehrlichia canis | Ocular bleeding reported in 29.4 percent of ocular ehrlichiosis cases [14] | Less commonly reported as a hyphema cause | ## Risk Factors and Signalment Age, breed, and history all shift the probability of each cause. Older dogs are more likely to have retinal disease, systemic hypertension, and neoplasia. The mean age in the retinal-origin hyphema study was 11.5 years [10]. The average age in the ocular gliovascular syndrome study was 8.8 years [12]. Labrador Retrievers had a significantly higher relative risk of canine ocular gliovascular syndrome in one database analysis [12]. That finding applies to one specific syndrome and should not be generalized to all hyphema. Young dogs are more likely to have trauma. The median age in the sports ball injury study was 1.0 year [2]. Dogs with a known bleeding disorder, a recent tick exposure, a history of porcupine encounter, or a diagnosis of cancer carry higher risk for specific causes [14][3][6]. Dogs with kidney disease, endocrine disease, or a recent drug exposure may have hypertension as the underlying cause [8][9]. ## How Veterinarians Examine a Red Eye The examination follows a fixed sequence. Each step answers a specific question. The first step is a general physical exam. The veterinarian looks for bruising, bleeding from other sites, pale gums, enlarged lymph nodes, or evidence of systemic illness. A dog with hyphema from a coagulopathy may have petechiae on the gums or blood in the stool. The second step is a vision assessment. Menace response, dazzle reflex, and pupillary light reflexes are tested in both eyes. The consensual pupillary light reflex, which is the pupil response in the opposite eye when light is shone into the affected eye, is a key prognostic marker. In the 99-dog hyphema series, an absent consensual pupillary light reflex raised the odds of blindness by 28.6 times, and an absent dazzle reflex raised them by 19.4 times [1]. These are simple bedside tests with major implications. The third step is tonometry to measure intraocular pressure. Elevated pressure is a red flag. In the same series, elevated intraocular pressure raised the odds of blindness by 9.1 times [1]. The fourth step is a slit-lamp or magnified exam of the anterior segment. The veterinarian looks at the cornea, the anterior chamber, the iris, and the lens. Blood in the chamber is graded by how much of the chamber it fills. Fibrin clots may be visible. The fifth step is fluorescein staining to check for corneal ulcers. This step is mandatory before any topical steroid is considered. A corneal ulcer treated with a steroid can worsen rapidly and may progress to a melting ulcer or perforation. The sixth step is a fundic exam, which is often limited by blood in the anterior chamber. When the view is blocked, ocular ultrasound is used. Ultrasound can detect retinal detachment, intraocular masses, and lens displacement behind the cloudy cornea. In the retinal-origin hyphema study, ultrasound identified retinal detachments that could not be seen directly [10]. The seventh step is a blood pressure measurement. This is non-negotiable in any dog with hyphema. It is also indicated in any dog with retinal detachment or retinal hemorrhage [8]. The eighth step is laboratory testing. A complete blood count checks for anemia and platelet count. A platelet count below the normal range points to thrombocytopenia. A coagulation panel checks the clotting pathways. A chemistry panel checks kidney values, liver values, and proteins. In some cases, specific testing for tick-borne disease, Brucella, or immune-mediated disease is added [14][13]. ## The Decision Path From Red Eye to Diagnosis The flowchart below shows the main decision path a veterinarian follows when a dog presents with a red eye. ```mermaid flowchart TD A[Red eye in a dog] --> B{Blanches with phenylephrine} B -->|Yes| C[Conjunctival hyperemia] B -->|No| D[Blood in anterior chamber] C --> E[Check tear production and stain] D --> F[Measure intraocular pressure] F --> G[Measure blood pressure] G --> H[Check platelet count and clotting] H --> I[Ultrasound the eye] I --> J{Retinal detachment or mass} J -->|Yes| K[Refer to ophthalmologist] J -->|No| L[Medical management and recheck] L --> M{Pressure high or bleeding persists} M -->|Yes| K M -->|No| N[Continue treatment and monitor] ``` ## Evidence-Based Management of Hyphema Treatment of hyphema in dogs has two goals. The first is to protect the eye and preserve vision. The second is to treat the underlying cause. Neither goal can be met without a diagnosis. ### Rest and Activity Restriction Dogs with hyphema are usually kept quiet. Exercise and excitement raise blood pressure and can trigger rebleeding. Strict rest is a standard part of initial management. ### Intraocular Pressure Control Elevated pressure must be lowered to protect the optic nerve. In the 99-dog series, 31.4 percent of eyes developed glaucoma, and the risk was higher when hyphema had been present for 8 to 30 days [1]. This is why early pressure measurement and early treatment matter. Medications to lower intraocular pressure are chosen by the veterinarian based on the cause and the presence of uveitis. Some drugs that lower pressure can worsen uveitis, so the choice is not automatic. Surgical options exist for uncontrolled glaucoma. Diode laser transscleral cyclophotocoagulation maintained intraocular pressure within the normal range in 22 of 24 eyes in one study [15]. Ahmed valve implantation is another option, and in two dogs that needed a second valve, hyphema occurred after surgery and resolved with anti-inflammatory treatment or clot removal [16]. These procedures are performed by ophthalmologists. ### Anti-Inflammatory Therapy Inflammation drives much of the damage in hyphema. Uveitis causes pain, miosis, and breakdown of the blood-aqueous barrier, which allows more protein and cells into the eye. Controlling inflammation is a core treatment goal. Topical steroids are effective for uveitis but are contraindicated when a corneal ulcer is present. A fluorescein stain must be performed before any steroid is used. If an ulcer is found, the treatment plan changes to address the ulcer first. Systemic anti-inflammatory drugs may be used when the cause is systemic or when topical therapy is not enough. The choice depends on the underlying disease. For example, a dog with Brucella canis needed systemic antibiotics to resolve the ocular inflammation after topical therapy failed [13]. ### Treating the Underlying Cause The eye will not recover if the cause is not addressed. Hypertension is treated with antihypertensive medication. In the phenylpropanolamine overdose case, blood pressure control resolved the hyphema and retinal detachment within one month [9]. Coagulopathies are managed based on the specific defect. A platelet procoagulant defect may require platelet support or specific therapy during bleeding episodes [6]. Infectious causes are treated with the appropriate antimicrobial. The Brucella case resolved after systemic antibiotics, and the ocular infection appeared to be eliminated [13]. Neoplasia may require surgery, chemotherapy, or enucleation depending on the type and extent. The ocular gliovascular syndrome study reported an average time to enucleation or evisceration of 27 days, which reflects how quickly some neoplastic and glaucomatous eyes deteriorate [12]. ### Pain Control Hyphema is often painful. Pain control is part of humane care and also reduces stress, which can help keep blood pressure stable. The specific drugs are chosen by the veterinarian. ### Monitoring and Rechecks Dogs with hyphema need frequent rechecks. Intraocular pressure can change quickly. The recheck schedule is set by the veterinarian based on the severity and cause. A dog with mild hyphema and a clear cause may be seen weekly at first. A dog with severe hyphema or glaucoma may be seen daily or every few days. ## Unsafe Home Remedies and Common Mistakes Several well-meaning home treatments can harm a dog with a red eye. Do not use leftover topical steroids from another pet or a previous prescription. A steroid applied to a corneal ulcer can make the ulcer worse and can lead to perforation. The ulcer may not be visible to an owner. Do not use human eye drops unless a veterinarian prescribes them. Some human products contain preservatives or active ingredients that are not safe for dogs. Do not try to flush the eye with tap water or homemade solutions. This can introduce bacteria and cause more irritation. Do not wait to see if the blood clears on its own. Blood in the anterior chamber can be the first sign of a clotting disorder, high blood pressure, or cancer. Waiting allows pressure to rise and the retina to detach. Do not give aspirin or other human pain relievers. Some of these drugs affect platelets and can worsen bleeding. Do not assume the redness is just allergies because the dog has had allergies before. A new problem can appear on top of an old one. ## Prevention and Reducing Risk Not every cause of hyphema can be prevented, but some risks can be lowered. Keep dogs away from porcupines and snakes when possible. If a dog has had a porcupine encounter, tell the veterinarian even if the eye looks normal at the time, because quill injuries can appear weeks to years later [3]. Use caution with high-speed balls around dogs. Small dense balls such as golf balls and baseballs caused the most severe injuries in the projectile study [2]. Manage underlying diseases that affect blood pressure. Dogs with kidney disease or endocrine disease should have blood pressure checked regularly [8]. Use tick prevention. Ehrlichia canis is a tick-borne disease that can cause ocular bleeding [14]. Follow up on any diagnosed bleeding disorder. Dogs with known platelet or clotting defects need careful monitoring and a plan for bleeding episodes [6]. ## Prognosis: What Owners Should Expect The prognosis for hyphema in dogs depends almost entirely on the cause. Causes with poor visual outcomes include ocular neoplasia, chronic uveitis, and trauma [1]. In the 99-dog series, 55.4 percent of eyes were blind at the final recheck [1]. Causes with better outcomes include hypertension that responds to treatment and some infectious diseases that respond to antimicrobials. The phenylpropanolamine overdose case resolved completely within a month [9]. The Brucella case resolved after systemic antibiotics [13]. Several exam findings predict a worse outcome. These include absent consensual pupillary light reflex, absent dazzle reflex, elevated intraocular pressure, retinal detachment, unilateral hyphema, and complete hyphema [1]. An owner does not need to memorize these, but they explain why the veterinarian performs each test. Globe retention is a separate question from vision. In the 99-dog series, enucleation was performed or recommended in 39.5 percent of eyes [1]. Enucleation is sometimes the best option for a painful, blind eye, especially when cancer is involved. ## Emergency Red Flags Some signs mean the eye needs care within hours. - Sudden onset of blood inside the eye - A pupil that does not respond to light in either eye - A cloudy cornea that appeared quickly - Squinting with the eye held tightly closed - A hard or swollen eye - Vomiting, lethargy, or bleeding from other sites such as the nose or gums - Known or suspected trauma to the head or eye - A dog that is suddenly bumping into things or seems blind - A red eye in a dog with a known bleeding disorder or cancer Any of these signs should prompt a call to a veterinarian or an emergency clinic. ## Limitations and When to Contact a Veterinarian This article covers general principles. It cannot replace an exam, a blood pressure reading, or a laboratory panel. Individual dogs need individual assessment. Contact a veterinarian the same day if a dog has blood visible inside the eye, a pupil that does not react to light, a cloudy cornea, or signs of pain such as squinting and light avoidance. Contact a veterinarian within 24 hours if a dog has a red eye that does not improve, a red eye with discharge, or a red eye in a dog with a known systemic disease. Ask for a referral to a veterinary ophthalmologist if the intraocular pressure is elevated, if a retinal detachment is found, if a mass is seen inside the eye, or if the bleeding does not resolve with treatment. These situations need specialized equipment and surgical options that general practices may not have. ## Frequently Asked Questions ### What does hyphema look like in a dog? Hyphema looks like blood inside the front chamber of the eye. It often settles at the bottom as a dark red crescent or fluid line, and a complete bleed can make the whole eye look dark. ### Is hyphema in dogs an emergency? Yes. Hyphema in dogs is an emergency because it can be the first sign of a bleeding disorder, high blood pressure, retinal detachment, or cancer, and because it can quickly lead to glaucoma and blindness. ### Can bloodshot eyes in dogs be just allergies? Yes, surface redness from allergies is common and usually blanches with a vasoconstrictor. Blood inside the eye does not blanch and is not an allergy. ### Why does my dog have blood in the eye with no injury? Systemic causes such as high blood pressure, clotting problems, and retinal disease can produce hyphema without any visible trauma. This is why blood pressure and blood tests are needed. ### Are topical steroids safe for a red eye in dogs? Topical steroids are not safe if a corneal ulcer is present. A fluorescein stain must be done first, because steroids can make an ulcer much worse. ### What tests will my veterinarian run for hyphema? Expect a blood pressure measurement, a platelet count, a coagulation panel, a chemistry panel, and an ocular ultrasound. Additional tests for infection or immune disease may be added based on the findings. ### Can hyphema in dogs resolve on its own? Some cases improve with treatment of the underlying cause, but the blood itself is not the main problem. Without diagnosis and treatment, many dogs develop glaucoma or lose vision. ### When should a dog with hyphema see a specialist? Referral is indicated when intraocular pressure is high, when a retinal detachment or mass is found, or when the bleeding does not resolve with initial treatment. ## Related Articles - [Why Is My Cat having bloodshot eyes? 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[Causes and outcomes of dogs presenting with hyphema to a referral hospital in Colorado: a retrospective analysis of 99 cases.](https://pubmed.ncbi.nlm.nih.gov/28782234/) 2. [Sports ball projectile ocular trauma in dogs.](https://pubmed.ncbi.nlm.nih.gov/35384230/) 3. [Ocular porcupine quilling in dogs: Gross, clinical and histopathologic findings in 17 cases (1986-2018).](https://pubmed.ncbi.nlm.nih.gov/33332752/) 4. [Canine ocular and periocular snakebites requiring enucleation: A report of 19 cases.](https://pubmed.ncbi.nlm.nih.gov/30716186/) 5. [Ophthalmic abnormalities secondary to periocular or ocular snakebite (pit vipers) in dogs--11 cases (2012-2014).](https://pubmed.ncbi.nlm.nih.gov/25912317/) 6. [A hereditary bleeding disorder of dogs caused by a lack of platelet procoagulant activity.](https://pubmed.ncbi.nlm.nih.gov/11895776/) 7. [Hyphema and secondary glaucoma as a presenting complaint in a dog with chronic lymphocytic leukemia.](https://pubmed.ncbi.nlm.nih.gov/36415701/) 8. [Systemic hypertension and its management.](https://pubmed.ncbi.nlm.nih.gov/9348634/) 9. [Systemic hypertension and hypertensive retinopathy following PPA overdose in a dog.](https://pubmed.ncbi.nlm.nih.gov/23148140/) 10. [Hyphema associated with retinal disease in dogs: 17 cases (1986-1991).](https://pubmed.ncbi.nlm.nih.gov/8496090/) 11. [Use of Transcorneal Iris Photocoagulation to Facilitate Sector Iridectomy of Pigmented Iridal Tumors: A Case Series of Five Eyes (Three Dogs and One Cat)-Clinical Findings, Surgical Technique, Complications, and Outcome.](https://pubmed.ncbi.nlm.nih.gov/40931895/) 12. [Clinical and histological characteristics of canine ocular gliovascular syndrome.](https://pubmed.ncbi.nlm.nih.gov/25174277/) 13. [Clinical resolution of Brucella canis-induced ocular inflammation in a dog.](https://pubmed.ncbi.nlm.nih.gov/15198266/) 14. [Ocular signs of canine monocytic ehrlichiosis: a retrospective study in dogs from Barcelona, Spain.](https://pubmed.ncbi.nlm.nih.gov/16359361/) 15. [Diode laser transscleral cyclophotocoagulation for the treatment of primary glaucoma in 18 dogs: a retrospective study.](https://pubmed.ncbi.nlm.nih.gov/11722786/) 16. [Sequential Ahmed valve implantation after primary implant surgery in two dogs.](https://pubmed.ncbi.nlm.nih.gov/37985376/)