However, nasopharyngeal symptoms alone do not establish an infection. A polyp, foreign object or narrowing can cause symptoms in the same area. Investigations assess both inflammation of the lining and whether air passes normally through the nose.
When to see a vet urgently
Contact a vet immediately if you notice any of the following:
- Your cat breathes with an open mouth or makes a visible effort to breathe.
- Your cat cannot swallow or eat normally and their condition is worsening.
- Breathing noises suddenly become louder and your cat seems distressed.
- A kitten is not eating, is very lethargic or appears dehydrated.
Handle a cat with breathing difficulties as calmly as possible. You can find a vet near you.
Overview
Nasopharyngitis is an inflammatory process affecting the nasopharynx, the part of the airway connecting the nasal and oral cavities. In cats, it can be acute or chronic. It most often develops as a complication of viral infection, but bacteria frequently sustain it.
More precisely, the nasopharynx lies behind the nasal cavity, above the soft palate. Inflammation may be part of the early stage of a viral infection and does not always require a separate preceding disease. Swelling and discharge can narrow the air passage.
The condition rarely occurs alone: cats most often have a broader respiratory disease involving rhinitis, inflammation of the trachea and bronchi, and conjunctivitis.
Lower airway inflammation is not part of every case of cat flu. Coughing, difficulty breathing or abnormal lung sounds may warrant chest investigation too. Nasal congestion alone does not establish bronchitis or pneumonia.
Causes
The main causes of nasopharyngitis in cats include:
- Viral infections: feline herpesvirus (FHV-1), calicivirus and, less commonly, coronaviruses.
- Bacteria, including Pasteurella, Bordetella and Mycoplasma.
- Fungal infections, less commonly and in areas where they occur.
- Allergic reactions causing prolonged irritation of the lining.
- Inhalation of dust, smoke and irritants.
- Parasitic diseases, such as nasopharyngeal parasites, which are extremely rare.
Herpesvirus and calicivirus are key causes of ordinary acute upper respiratory infection. Findings of other microbes are interpreted separately; a single coronavirus finding, for example, does not itself establish the cause of nasopharyngeal symptoms. An allergic cause is also not assumed before more common and structural alternatives are assessed.
Persistent symptoms can also result from a nasopharyngeal polyp, foreign object, a connection to the nasal cavity associated with dental disease, a tumour or a stricture. A polyp is a benign tissue growth that can interfere with both breathing and swallowing. It occurs particularly in young cats.
Risk factors
- Young age, with kittens and young cats more susceptible.
- Crowded conditions, such as breeding catteries and shelters.
- Recent stress, including a house move, change of owner or surgery.
- Reduced immunity.
- Contact with sick animals or viral carriers.
After infection, herpesvirus can remain latent and reactivate later, for example during stress. Recurrent symptoms therefore do not always mean a new infection from another cat. A carrier without symptoms can also contribute to spread. A vaccinated or indoor-only cat can still become ill.
Being young does not rule out a structural problem, and persistent discharge in an older cat should not automatically be interpreted as continuation of previous cat flu. Age, duration and other findings help choose investigations, but do not establish the diagnosis alone.
Typical symptoms
Nasopharyngitis in cats causes breathing problems and a decline in general health:
- Noisy or difficult breathing.
- Sneezing, sometimes in bouts.
- Nasal discharge that may be clear, mucoid or purulent.
- Coughing and gagging.
- Reduced appetite or refusal to eat because of breathing difficulties and a reduced sense of smell.
- Lethargy, apathy and reduced activity.
- A possible rise in body temperature.
- Watery eyes and conjunctivitis if the inflammation is part of cat flu.
Nasopharyngeal disease can also cause snorting during inhalation, repeated swallowing or gagging without actual vomiting. Report whether the noise occurs at rest, during sleep or during activity, and whether swallowing has changed. A safely recorded short video can help describe an intermittent symptom.
Note whether discharge comes from one or both nostrils and whether it contains blood. Persistent one-sided discharge, changes in facial shape or continuing difficulty swallowing may require broader investigation. Yellow or greenish discharge alone does not confirm a bacterial cause.
Not eating can result from painful mouth ulcers or nausea as well as reduced smell. A cat that approaches food but stops eating needs assessment just as one that refuses food entirely does.
Complications and consequences
Without treatment, nasopharyngitis can lead to:
- A chronic form with persistent nasal discharge and noisy breathing.
- Secondary bacterial infections.
- Bronchitis and pneumonia.
- Ulcers in the mouth lining with calicivirus infection.
- Wasting and dehydration from not eating or drinking.
- In severe cases, death in kittens and cats in poor condition.
Mouth ulcers may be a concurrent manifestation of calicivirus, rather than necessarily a complication spreading from the nasopharynx. Nor does every cat develop pneumonia. Recognising deteriorating health and inadequate food or fluid intake is essential.
Persistent damage to the lining after viral infection can cause ongoing symptoms even when the original agent can no longer be reliably identified. Chronic rhinitis treatment may therefore aim to control symptoms rather than guarantee a permanent cure.
Diagnosis at the vet
An accurate diagnosis may use:
- Clinical examination and assessment of breathing sounds.
- Nasopharyngeal endoscopy in chronic disease.
- Laboratory tests, including viral PCR and bacterial cultures.
- X-rays or CT to rule out tumours and polyps.
- A complete blood count to assess inflammation.
Breathing and general health are assessed first
Your vet listens to breathing and assesses breathing effort, nasal airflow, hydration and food intake. The mouth, teeth, eyes and ears may provide further clues. Necessary supportive care begins before stressful investigations if your cat's condition requires it.
What does a microbial test show?
PCR looks for a pathogen's genetic material, but the result alone does not show that the detected microbe is causing the current symptoms. A healthy carrier can test positive. Conversely, a negative result does not always exclude infection. Sampling site and the stage of symptoms affect interpretation.
Bacteria can also be found in the nose or throat of a healthy cat. A superficial culture therefore does not automatically indicate a need for antibiotics. Your vet selects samples and tests according to the clinical question, particularly if disease persists or the treatment response is inadequate.
Endoscopy, imaging and samples
CT shows changes in the nose and surrounding structures in more detail than X-rays. Endoscopy allows examination of the nasopharynx, a search for foreign objects and sampling. These investigations may need sedation or general anaesthesia, whose safety is assessed individually.
Imaging alone does not always distinguish a tumour, inflammation and fungal disease. A biopsy or another targeted sample may be needed. An ordinary X-ray also cannot reliably rule out every polyp or small lesion. Not every mildly sneezing cat undergoes all these tests.
Treatment
Treatment depends on the cause:
- Viral disease requires supportive care, including humidification, cleaning the nose, warm food with a strong aroma and, where needed, a vet-prescribed antiviral for herpesvirus; immune-boosting products and vitamins have no demonstrated effectiveness.
- Secondary bacterial complications are treated with vet-prescribed antibiotics.
- Anti-inflammatory and mucus-loosening medicines may ease breathing.
- Fluids treat dehydration.
- Complete nutrition and humid indoor air support care.
Medicines are chosen according to findings. Antibiotics do not work against viruses and are not automatically needed for every case of nasal discharge. Herpesvirus treatment is assessed separately; it does not eliminate latent carriage. Medicines that reduce inflammation or discharge are not given to every cat in the same way either.
If a polyp, foreign object or another obstruction is responsible, treating infection alone may not resolve the problem. A polyp, for example, may need removal. Confirmed fungal disease is treated for the particular agent, rather than selecting an antifungal solely because of nasal discharge.
Home care and supporting eating
Gently clean visible nasal and eye discharge according to your instructions. Humidification may ease symptoms, but must not burden a cat with breathing difficulties. Stress from handling and giving medicines is considered in the care plan.
Offer appealing food in a quiet place and monitor actual intake. Pain and nausea are treated when necessary. Avoid force-feeding; inadequate nutrition may require a feeding tube. A dehydrated or poorly cat may need hospital care even when home care is enough for milder symptoms.
Record changes in breathing, discharge, appetite and alertness. New breathing difficulties, clearly increased pain or deteriorating general health are assessed before the planned follow-up. Do not repeatedly treat persistent symptoms with old medicines without reassessing the cause.
Prevention
- Vaccinate your cat regularly against the main feline viruses, including herpesvirus and calicivirus.
- Reduce stress.
- Keep the environment clean and avoid contact with sick animals.
- Support immunity through appropriate feeding and care.
- Attend regular veterinary examinations.
Vaccination particularly reduces disease severity, but does not guarantee prevention of every infection or carrier state. The vaccination plan is adapted to your cat. Keep a sick cat separate from others as instructed, and maintain the cleanliness of shared bowls and care equipment.
Cleaning and disinfection are separate stages: visible dirt is removed before suitable disinfection. Choose the product for the surface and pathogen, because calicivirus, for example, resists many substances better than herpesvirus. Follow instructions, and do not apply strong substances to a cat's mucous membranes.
Important for cat owners
Nasopharyngitis is a common condition most often associated with viral respiratory infections. Remember that even an ordinary bout of cat flu can quickly develop complications and become chronic. Seeking veterinary care promptly prevents serious consequences and helps your cat stay healthy and active.
Early care reduces risk, but not every consequence or recurrent episode can be prevented. Persistent symptoms sometimes need long-term monitoring and treatment adjustments.
This article provides general information and does not replace veterinary care. Contact a vet if you notice signs of illness in your cat.
Frequently asked questions
Is noisy breathing always cat flu?
No. A nasopharyngeal polyp, foreign object, stricture and other structural changes can cause similar symptoms. Persistent or worsening noise is investigated before further medicine trials.
Does purulent nasal discharge always need an antibiotic?
The discharge's appearance alone does not establish a bacterial cause. Antibiotic need is assessed according to general health, examination findings and any samples.
Can a vaccinated cat become ill?
Yes. Vaccination reduces severity, but protection does not always prevent infection or viral carriage. Breathing difficulties and not eating in a vaccinated cat also need investigation.
When does a cat with nasal discharge that is not eating need help?
Contact a vet without delay, particularly for a kitten or if your cat is painful or deteriorating. A cat breathing with an open mouth or obvious difficulty needs emergency assessment.
This article is for general information only and is not a guide to treatment. If you notice the first signs of illness, contact your vet.
Paw4care editorial team
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