Horse Bloody Nose or Blood-Tinged Nasal Discharge: Causes & Emergencies

Blood from one or both nostrils is called epistaxis. In horses, it is a symptom rather than a diagnosis. Some causes are relatively localized, like a small nasal injury, while others involve the lungs, sinuses, guttural pouches, or the horse's clotting system. Because the range is so wide, even a small amount of blood should be taken seriously.

One important cause is guttural pouch mycosis, a fungal infection that can erode major arteries inside the guttural pouch. Horses may first show intermittent mild nosebleeds, trouble swallowing, noisy breathing, or facial nerve changes. This condition is considered life-threatening because repeated bleeding episodes can happen before a catastrophic hemorrhage.

Another well-known cause is exercise-induced pulmonary hemorrhage (EIPH), where blood enters the airways after strenuous exercise. This is common in racehorses and other high-intensity equine athletes, but visible blood at the nostrils happens in only a small percentage of affected horses. Other causes include progressive ethmoid hematoma, sinus disease, pneumonia or lung abscesses, foreign material, trauma, and less commonly tumors or systemic bleeding disorders.

Whether the discharge is one-sided or two-sided, associated with exercise, mixed with mucus, or accompanied by coughing, fever, poor performance, or trouble swallowing helps your vet narrow the list. A one-sided intermittent bleed raises concern for problems like ethmoid hematoma or guttural pouch disease, while bleeding after hard exercise may point more toward EIPH.

See your vet immediately if bleeding is active, heavy, recurrent, or your horse seems weak, distressed, or is having trouble breathing or swallowing. The same is true if blood appears after exercise, if there is blood from both nostrils, or if your horse also has coughing, fever, poor performance, facial asymmetry, choke-like episodes, or neurologic signs. These patterns can be linked with serious airway or guttural pouch disease.

A horse with even a small amount of blood-tinged discharge should usually be examined the same day or as soon as possible. Mild bleeding can look less dramatic than it is. Guttural pouch mycosis, for example, may begin with brief, intermittent nosebleeds before a severe hemorrhage occurs.

There are very few situations where home monitoring alone is appropriate. If your horse bumped its nose and you see a tiny amount of blood once, then it stops completely and your horse is otherwise normal, your vet may advise quiet observation. Even then, call for guidance first. Do not return the horse to work until your vet says it is safe.

While waiting, keep your horse calm in a well-bedded stall or small paddock, avoid exercise, and note which nostril is bleeding, how much blood you see, and whether it happened after work, coughing, or eating. If your horse seems infectious or febrile, ask your vet before transporting.

Your vet will start with a focused history and physical exam. Expect questions about when the bleeding started, whether it followed strenuous exercise, whether it is one-sided or two-sided, and whether your horse has had coughing, poor performance, trouble swallowing, fever, trauma, or previous episodes. That history matters because the pattern of bleeding often helps localize the source.

A common next step is upper airway endoscopy, which lets your vet examine the nasal passages, pharynx, guttural pouches, larynx, and trachea. Endoscopy is especially important when your vet is concerned about guttural pouch mycosis, ethmoid hematoma, or blood coming from deeper in the airway. If EIPH is suspected, endoscopy is most useful within about 30 to 120 minutes after exercise, and some horses may also need bronchoalveolar lavage or other lower-airway testing.

Depending on the findings, your vet may recommend bloodwork such as a CBC and clotting tests, plus imaging like skull radiographs, ultrasound, or referral imaging. Horses with lower-airway signs may need thoracic evaluation, while horses with sinus or dental concerns may need head imaging. If bleeding is significant, referral and hospitalization may be recommended quickly.

Treatment depends on the cause. Options may include stall rest and monitoring, medications directed by your vet, guttural pouch procedures, treatment for infection, management changes for EIPH, or emergency surgery or vascular occlusion for severe guttural pouch bleeding. The goal is to stabilize the horse, identify the source, and reduce the risk of another bleed.

Home care is supportive only. It does not replace a veterinary exam for a horse with a bloody nose. Keep your horse quiet, avoid exercise, and reduce stress while you wait for your vet. If your horse is actively bleeding, do not force movement unless safety requires it.

Offer a calm, dust-controlled environment and watch for changes in breathing, swallowing, coughing, or attitude. If your horse seems to choke, drops feed, or has nasal discharge mixed with feed material, remove hay and grain and call your vet right away. Write down when the bleeding started, whether it followed exercise, and whether it came from one nostril or both.

Do not put anything into the nostrils unless your vet instructs you to. Do not give medications, including anti-inflammatories or supplements, unless your vet says they are appropriate for this specific case. Some horses with bleeding may need clotting tests or other diagnostics before medications are chosen.

After your vet identifies the cause, home care may include stall rest, careful return-to-work planning, medication administration, feeding adjustments if swallowing is affected, and close monitoring for recurrence. If bleeding starts again at any point, treat it as urgent and contact your vet immediately.