Why Is a Cat Sneezing Blood With an Upper Respiratory Infection?

Cats can sneeze blood with an upper respiratory infection (URI) or a more severe respiratory disease due to irritation and secondary bacterial infection. URI typically causes inflammation and swelling in the nasal passages, throat, and sinuses. This inflammation can lead to increased mucus production, which can cause cats to sneeze. If the infection is severe, it can lead to damage to the blood vessels in the nose, resulting in bleeding and blood-tinged mucus.