Sneezing in Cats — Symptom Decision Guide

A practical guide to chronic sneezing in cats: what to look for, likely causes (herpesvirus, chronic rhinosinusitis, polyp, dental disease, tumor, foreign body), home checks, and when to seek veterinary care.

Quick Assessment

Is this an emergency?

- Yes: if your cat has rapid or difficult breathing, severe lethargy, cannot eat/drink, heavy bleeding from the nose, or a fever over 103 F (39.4 C). Seek immediate veterinary care.

- No (but see a vet): chronic sneezing that continues for more than 3 weeks, recurrent episodes, or sneezing with persistent nasal discharge, weight loss, or poor appetite.

Most common cause: chronic upper respiratory infection or chronic rhinosinusitis (including feline herpesvirus-1 sequelae).

When to see a vet: sneezing that lasts longer than 3 weeks, any worsening signs, unilateral bloody/mucopurulent discharge, facial swelling, or any emergency signs above.

What chronic sneezing looks like

Chronic sneezing means repeated sneezes or paroxysms of sneezing that persist or recur over weeks to months. Owners often report:

• Frequent bouts of sneezing several times per hour or persistent intermittent sneezing for >3 weeks
• Runny nose (serous, mucoid, mucopurulent, or bloody discharge)
• Snorting sounds, nasal congestion, or stertor
• Reluctance to eat because of nasal/ mouth discomfort
• Intermittent improvement with antibiotics or home measures but relapse afterward

Possible causes, ranked by likelihood

Note: bacterial infection may complicate any listed cause but is less often the primary reason for chronic sneezing.

Decision tree: If [symptom] + [other sign] → likely [cause] → [action]

• If sneezing + bilateral clear watery eye/nasal discharge + history of prior upper respiratory infection or stress → likely FHV-1-related chronic inflammation → action: schedule vet visit for exam; consider antivirals/supportive therapy and stress reduction; isolate from other cats until evaluated.

• If sneezing + intermittent mucopurulent or bloody discharge, adult cat, no obvious cause, months-long history → likely chronic rhinosinusitis → action: vet exam; diagnostics often include oral exam, nasal flush/cytology, radiographs or CT, and possibly biopsy.

• If sneezing + unilateral mucopurulent discharge + bad breath or visible dental disease → likely dental disease/oronasal fistula → action: urgent dental assessment by vet; oral radiographs and dental treatment may be needed.

• If sneezing + gagging/stridor and a young cat with ear or throat involvement → likely nasopharyngeal polyp → action: veterinary ENT examination and likely referral for sedation and polyp removal; imaging may be required.

• If sneezing + sudden onset unilateral sneezing/squinting + pawing at nose after outdoor activity → likely foreign body → action: see vet promptly; rhinoscopy or imaging to locate and remove object.

• If sneezing + progressive unilateral bloody discharge or facial swelling in an older cat → likely nasal tumor → action: urgent veterinary workup including CT and biopsy; early diagnosis helps guide treatment and prognosis.

Home assessment steps (what to check and measure)

Keep a brief log (dates, symptoms, photos) to bring to the vet.

When it is an emergency — red flags

Seek immediate veterinary care if you observe any of the following:

• Severe labored breathing, open-mouth breathing, or blue/pale gums
• Uncontrolled bleeding from the nose
• Severe lethargy, collapse, inability to stand
• Refusal to eat or drink for more than 24 hours in a cat with other signs
• High fever over 103 F (39.4 C)
• Sudden onset of severe facial swelling or neurologic signs (head tilt, circling, seizures)

When to schedule a vet visit (non-urgent but needed)

Make a veterinary appointment within a few days if any of the following apply:

• Sneezing persists more than 3 weeks or keeps recurring
• Persistent mucopurulent or bloody nasal discharge (especially if unilateral)
• Weight loss, reduced appetite, or reduced grooming
• New facial swelling, halitosis, or dental disease signs
• Multiple cats in household are affected

Home care while you wait

Do not attempt to self-diagnose or give human medications without veterinary approval. Safe supportive measures include:

• Keep the cat comfortable and warm. Use a humidifier or sit with the cat in a steamy bathroom for 10 minutes to help loosen mucus.
• Gently clean nasal discharge with a warm damp cloth. Keep eyes and nostrils clear so breathing is easier.
• Encourage eating: offer palatable, warmed food or strong-smelling canned food if smell/taste are affected.
• Keep the environment smoke-free and reduce stress (quiet room, hiding places).
• Isolate affected cats from others if you suspect an infectious cause.
• Do not use over-the-counter decongestants, antihistamines, or antibiotics unless prescribed by your veterinarian.

What your veterinarian may do

Your vet will perform a full physical and oral exam and may recommend:

• Digital rectal temperature, blood tests, and fecal/parasite check if indicated
• Oral/dental exam and dental radiographs
• Nasal cytology, culture, or PCR testing for viral pathogens like FHV-1
• Rhinoscopy to visualize and possibly remove foreign material or take biopsies
• Skull radiographs or CT imaging for tumors, chronic rhinitis, or complicated dental disease
• Biopsy of masses or inflamed tissue if needed

What to tell your vet (prepare this information)

• Exact duration of sneezing and pattern (continuous vs intermittent)
• Description of nasal discharge and whether it is unilateral or bilateral
• Any bleeding from the nose and when that started
• Appetite, water intake, weight changes, activity level
• Dental history, recent dental cleanings or problems
• Vaccination status (especially for feline herpesvirus and calicivirus)
• Exposure to other cats, shelter history, or new introductions
• Any treatments tried and response (antibiotics, home remedies, supplements)
• Indoor/outdoor status and possible exposure to plants, grasses, or trauma

Final notes

Chronic sneezing in cats has many possible causes, from relatively benign chronic rhinitis to dental disease or nasal tumors. Early veterinary evaluation improves the chance of finding a treatable cause and prevents complications. Keep records of signs and share them with your veterinarian to speed diagnosis and appropriate care.

Primary source: Merck Veterinary Manual, Upper Respiratory Infections in Cats and Chronic Rhinosinusitis entries. For owners: see Merck Vet Manual cat owner pages for more on nasal disease and diagnostic approaches.

Citation: Merck Veterinary Manual — Upper Respiratory Infections in Cats. https://www.merckvetmanual.com/cat-owners/respiratory-system/upper-respiratory-infections-in-cats

Frequently Asked Questions