Epistaxis is defined as acute hemorrhage from the nostril, nasal cavity, or nasopharynx. It is commonly referred to as a "nosebleed." A bleeding nose can come from several sources. Most acute or sudden nosebleeds are caused by simple trauma or by upper respiratory tract infections. Additionally, nose bleed is usually from damaged vessels in the nasal mucosa but can also be due to an increased fragility of capillaries or bleeding tendencies. There are various other and some very serious causes of this condition and require prompt medical help.
The bleeding may be acute (sudden) or chronic (long standing). How ill the animal becomes often is determined by the underlying cause of the nasal bleeding.
The most common symptom of this condition is nose bleed. It can be just a few drops here and there or a steady dribble of blood from the nose. Other symptoms include
Sneezing, accompanied by a large spray of blood
Severe dental disease
Black, tarry stool (caused by swallowing blood)
A foul odor from the mouth or nose
Loss of appetite