There are many reasons why a cat sneezes!
1. Viral infection: Mostly seen in unvaccinated cats. Sneezing, running nose, white to greenish discharge from nose, watery or yellowish discharge from eye is seen in Herpes Virus Infection. Calicivirus Infection also causes sneezing and discharge from eye and nose.
2. Bacterial and fungal infection: Chlamydia, Bordetella, and Mycoplasma infection cause sneezing.
3. Allergies or chemicals: Allergies to dust, pollen, molds, and chemicals like cigarette smoke, candle smoke, perfume, cat litter dust, or cleaning chemicals may irritate the nasal tract leading to sneezing.
4. Nasal tumor: Any tumor on nasal tract leads to sneezing.
5. Foreign body: Foreign body stuck in nasal tract leads to sneezing
Signs along with sneezing which may cause an alarming situation are eye discharge, nasal discharge, ulcers in eye or mouth, salivation, fever, coughing, difficulty in breathing, etc.
If your cat is sneezing continuously, take a soft cloth and wipe the discharge. Provide warm food and enough fresh drinking water for your kitty always.
If the condition is becoming worse take your pet to the vet. Your veterinarian may perform a physical examination, blood test, radiograph to find out the cause of sneezing. He may prescribe antibiotics, antiviral drugs, and supportive therapy if bacterial or viral infection is found. In allergy or irritant cases keeping away from allergen and providing warm air using a vaporizer is advisable. Fluid therapy is indicated if your cat becomes anorexic.