My young cat has been sneezing w/mucus coming from her nose since she was a kitten. What can be done?

Question: 

My 1 year old cat has sneezing attacks, during which mucus is expelled from her nostril. She has had these since she was a kitten. Our veterinarian has prescribed an antibiotic which provides some relief. What is causing this? Does she have allergies, and if so what can be done?

Answer: 

Chronic sneezing, nasal discharge, and snorting, sniffling is a common problem in cats and can be due to many different diseases. The most common one in young cats is called chronic rhinitis or chronic rhinosinusitis. This is a disease where the cause is believed to be related to a combination of latent herpes infection (a virus), secondary bacterial infections and an over active immune response. Many of these cats will respond partially to antibiotics for the secondary bacterial infections or lysine treatment for herpes virus http://www.expertvet.com/articles/feline-herpes-virus. Piroxicam (an NSAID) or prednisone (a steroid) can improve signs in some patients but in most the signs are chronic and a cure is rare. Allergies are not usually the cause for these signs in cats like they are in people. Other causes for these signs include nasal polyps (inflammatory masses in young cats), cancer, fungal infections, foreign bodies, dental disease, but other causes are also possible. To diagnose the condition, all other causes must be eliminated which usually requires advanced imaging (CT scan http://www.expertvet.com/articles/computed-tomography-ct) and nasal scoping (rhinoscopy) with biopsies. Please consult your veterinarian about these further diagnostics and treatments.