4 reasons why your cat won't stop sneezing, from allergens to nasal blockages

• Cats sneeze from time to time, and you usually don't need to worry about a stray sneeze or two. 
• Respiratory infections, allergies, vaccines, and nasal blockages may cause more frequent sneezing.
• If your cat keeps sneezing multiple times in a row or for several days, it's best to call a vet.

As a cat owner, you likely pay close attention to any sign that your feline friend feels less than purr-fect — like sneezing. 

A solitary sneeze is typically nothing to fret over — your cat is probably dislodging some stray dust in their nose.

However, sneezing could pose a cause for concern if it happens: 

• Frequently, or at least three times a day
• Multiple times in a row, aka paroxysmal sneezes
• Backwards, aka reverse sneezing — where your cat compulsively snorts in air

Excessive sneezing is often a sign of an issue with your cat's airways. Some of the causes have an easy at-home fix, while others require medical attention. 

Here are four reasons why your cat keeps sneezing, and what you can do to help.

1. Allergens

 "There are several household allergens and irritants that can cause sneezing or coughing in cats," says Patrik Holmboe, head veterinarian at Cooper Pet Care. 

According to Holmboe, the most common allergens include:

• Dust
• Mold
• Cigarette smoke
• Cleaning products
• Perfumes

These allergens can also cause breathing issues in humans. However, because cats rely so much on their noses for hunting and communication, they're likely to show symptoms before you do.

Cats are like a canary in a coal mine, so to speak, according to Stefanie Wolf, veterinarian at The Vets. "If the family cat is having trouble breathing, over time whatever is causing it may lead to health problems among human family members, as well," Wolf says. 

Cats are especially susceptible to smoke. In fact, Wolf says cats commonly have breathing problems in homes where a family member smokes indoors. "While they have the strongest reaction to cigarette smoke, the same applies to vaping and cannabis," Wolf says.

What to do next: "Whenever a kitty has a breathing problem, the first step is to eliminate everything in the home with an odor," Wolf says. 

You can clear out the air by:

• Smoking or vaping outside the home
• Vacuuming carpets regularly
• Cracking open windows on nice days — just make sure your cat can't sneak out
• Putting an air purifier in your cat's favorite room

According to Wolf, you may want to schedule a vet appointment if your cat:

• Sneezes every day or multiple times a day
• Frequently hacks or wheezes
• Breathes rapidly when sleeping or relaxing
• Snores loudly 

Cats with severe allergies or asthma may benefit from medications, like corticosteroids to reduce inflammation or bronchodilators to open up their airways. A vet can prescribe these drugs as an injection, a tablet, or a cat-friendly inhaler.

2. Upper respiratory infections (URIs)

While allergies might be a culprit, your cat's sneezing is much more likely a symptom of an upper respiratory infection (URI), says Holmboe. 

URIs happen when viruses and bacteria attack your cat's upper airways around their mouth and nose. Many people refer to URIs as "cat flu," although strictly speaking, the influenza virus is rarely behind these infections.

According to Holmboe, most cases of the so-called cat "flu" are mild. Your cat will likely be as active and hungry as ever. Along with sneezing, you may notice they have a runny nose and teary eyes.

Severe URIs, though less common, may be more likely to affect kittens and older cats. Pay attention to symptoms like:

• Fever
• Loss of appetite
• Sores around the eyes or in the mouth
• Drooling
• Green, yellow, or bloody discharge coming out of the eyes and nose — this points to a bacteria infection

What to do next: Mild URIs generally clear on their own without treatment. You won't need to take your cat to the vet unless they continue sneezing for more than a week.

Stress can cause symptoms to flare up again. To minimize stressors in your cat's life:

• Ensure they have a quiet area to be alone
• Provide scratching posts and toys to relieve stress
• Keep their litter box extra clean, scooping at least once a day

Any symptom of a severe URI, however, warrants prompt medical attention. Regardless of what virus caused the symptoms, the treatment will generally include medications like:

• Antibiotics for bacterial infections
• Non-steroidal anti-inflammatory drugs (NSAIDs) for fever and mouth pain
• Vaporizers, saline nose drops, and mucus thinners for congested noses

3. Vaccines

Vaccines for pets can cause mild side effects, so you may notice some mild sneezing and coughing two to five days after your cat's vaccinations. 

Respiratory symptoms are particularly likely if they got an intranasal vaccine — a vaccine sprayed up their nose. 

What to do next: If your pet develops side effects, just keep an eye on them to make sure the side effects don't get worse.

Some pets do have severe allergic reactions to vaccines, though this is fairly rare. Symptoms of a severe reaction may include:

• Severe coughing or trouble breathing
• Swelling around the face, neck, or eyes
• Itchy red bumps on the skin, called hives
• Persistent vomiting or diarrhea

You'll want to take your cat to the vet immediately if they have any of these symptoms shortly after a vaccine — symptoms of a serious allergic reaction usually show up within a few hours.

4. Nasal blockages

Curiosity usually doesn't kill the cat — but it can get some interesting objects stuck up your feline friend's nose. 

According to a 2022 review, the most common foreign objects that appear in a cat's nose are plant materials: blades of grass, seeds, sticks, and sometimes even chunks of pine cone. So, if your outdoor cat suddenly starts sneezing, you can often thank these natural materials

Nasal polyps can also clog up your cat's airways. These fleshy growths aren't cancerous, but they can spread and become large enough to block mucus from draining out of the nasal passages. Bacteria in the trapped mucus then have the chance to multiply into a full-blown infection — and your cat may start sneezing in an attempt to expel the germs. 

What to do next: Nasal blockages can cause many of the same symptoms as URIs, like wheezing and teary eyes. You can tell if your cat has a blockage by checking their nose — or having your vet perform this (dubious) honor. 

A foreign object will only block the nostril it was inhaled into. Polyps also tend to favor one side — they often start in the middle ear and spread downward into the airways. Thus, you'll likely see discharge leaving only one nostril. Air will come out of the dry, open side, but you won't be able to feel much air coming out the congested half.

If an object or polyps are blocking your cat's airways, you'll need to take them to the vet — as the object probably won't come out on its own. 

The typical treatment for nasal blockages is a rhinoscopy. After sedating your pet, the vet will put a flexible tube, called an endoscope, up their nose. The tube has a fiber optic cable that shows your vet what's inside — though they may need to do a CT scan or MRI to find a deep blockage.

Once they find the trapped object or polyp, they may use a tiny hook or forceps to pluck it out. If it's a large or complex blockage, though, your cat may need surgery. After removing the object, your vet may prescribe some take-home antibiotics to prevent infection.

Insider's takeaway

Feline URIs are the most common cause of excessive sneezing and other upper airway concerns. However, your cat's sniffles could also stem from allergies, polyps, vaccine side effects, or simply something stuck up their nose.

If your cat's only symptoms are sneezing and a runny nose, you can likely care for them at home. But if your cat also wheezes, has bloody discharge leaking from their nose, or refuses to eat, you'll want to contact your vet right away. These symptoms could signal a serious problem that needs medical attention.