Just like humans, cats sneeze--although they never wipe their noses after. Cats usually sneeze once or twice with little nasal discharge. If cat sneezes often and the sneezing is accompanied by bloody discharge, it is time to contact a veterinarian.
A cat usually sneezes because something is irritating the tissue within its nasal passages. This can be caused by dust or allergens. A cat can also experience nasal discharge along with the sneezes. The discharge can take the form of a runny nose or the cat might sneeze it out. Nasal discharge is usually clear and watery, but it can also be thick and green or even bloody.
Bloody nasal discharge and bloody sneezes are caused by bleeding occurring within a cat's nasal passages. This bleeding can be caused by a foreign object that has lodged up a cat's nose, according to the "Cat Owner's Home Veterinary Handbook." Another cause of sneezing blood can be a fungal infection. Bloody nasal discharge can also be a symptom of cancer growing somewhere within a cat's nasal passages.
A veterinarian can diagnose the cause of a cat's bloody sneezes. An x-ray of a cat's skull can detect foreign objects. A veterinarian can also insert a mirror into a cat's mouth to view the back of the cat's nose. By flushing water through a cat's nose, she can get cell samples from its nasal passages for examination or biopsy. A CT scan can also provide images of the inside of a cat's skull.
If a foreign object is causing a cat to sneeze blood, then removing the blade of grass or seed will allow the cat's nasal tissues to heal and the bleeding will stop. Fungal infections can be treated with antifungal medication. Cancer within the nasal passages is difficult to treat. If a veterinarian can access it, the tumor can be removed surgically, followed by radiation therapy to destroy any remaining cancer cells, according to "What Your Cat Is Trying To Tell You."
If a cat sneezes blood, treatment could include antibiotics to prevent infection from wounds within the nasal passages. If the bloody sneezing is caused by inoperable nasal cancer, the tumor could continue to grow. The tumor could grow back into the cat's brain, causing seizures or behavioral problems. It could also break the bones in a cat's face, causing deformity, according to Washington State University. A veterinarian can help evaluate the cat's comfort and might recommend euthanasia to prevent further pain.