A cat that keeps sneezing and coughing is most likely dealing with a respiratory infection, though asthma, environmental irritants, and even parasites can produce the same combination of symptoms. The cause matters because some of these conditions clear up on their own in a week or two, while others need treatment to keep from getting worse.
Upper Respiratory Infections: The Most Common Cause
The vast majority of sneezing-and-coughing episodes in cats trace back to an upper respiratory infection, or URI. Two viruses account for most cases: feline herpesvirus and feline calicivirus. Both spread through sneeze droplets and contaminated objects (like shared food bowls or a handler’s clothing), which is why cats in shelters, boarding facilities, or multi-cat homes are especially vulnerable.
Herpesvirus tends to hit the eyes and nose hardest. You’ll typically see frequent sneezing, watery eyes, nasal congestion, and discharge that starts clear but turns thick and yellowish over a few days. Some cats develop fever, mouth sores, or eye ulcers. Calicivirus looks similar but tends to target the mouth and lungs. It’s more likely to cause sores on the tongue or gums, and in some cases it can move into the lower airways and cause pneumonia. A handful of calicivirus strains produce a temporary limping syndrome, with fever, leg lameness, and joint pain but no mouth sores.
One important detail about herpesvirus: after symptoms clear, the virus stays dormant in your cat’s body for life. Stress, illness, or anything that suppresses the immune system can reactivate it, causing repeat flare-ups. If your cat seems to get the same “cold” every few months, this is likely why.
Bacterial Infections and Secondary Complications
Bacteria can cause respiratory symptoms on their own, but they more commonly pile onto an existing viral infection. When a virus damages the lining of the airways, bacteria like Bordetella bronchiseptica and Mycoplasma felis can take hold and make things significantly worse.
Bordetella symptoms range from mild sneezing and coughing with some eye discharge to serious breathing difficulty. In severe cases, a cat’s gums can turn blue from lack of oxygen. Mycoplasma tends to cause eye inflammation with swelling and discharge, along with coughing, sneezing, lethargy, and loss of appetite. It can also become a chronic problem, settling into the sinuses and causing long-term nasal congestion and discharge.
Very young kittens, senior cats, and immunosuppressed cats are at highest risk for severe bacterial infections. In these animals, what starts as a simple URI can progress to pneumonia, dangerous dehydration from not eating or drinking, or even liver problems from prolonged refusal to eat.
Feline Asthma
If your cat’s coughing is chronic rather than part of a short illness, asthma is a strong possibility. Cats with asthma may wheeze, breathe rapidly, hack or cough repeatedly, and sometimes vomit afterward. During an attack, many cats crouch low to the ground with their neck stretched forward. Between episodes, they can seem perfectly normal.
Asthma happens when a cat’s immune system overreacts to something inhaled, triggering inflammation and constriction of the airways. Common triggers include:
- Dusty cat litter
- Cigarette smoke
- Air fresheners and scented candles
- Household cleaning chemicals
- Hairspray and powders
- Mold and pollen
There’s no single test that confirms feline asthma. Vets typically combine your cat’s history with chest X-rays, which often show a distinctive bright branching pattern along the airways from accumulated inflammatory cells. The lungs may also look overinflated from trapped air. In some cases, a small camera is passed into the airways to look directly at the lining and collect cell samples. Treatment usually involves reducing airway inflammation, and many cats with asthma are managed long-term with an inhaler designed for cats or with oral anti-inflammatory medication.
Heartworm-Associated Respiratory Disease
This one surprises most cat owners. Unlike dogs, where heartworms primarily damage the heart, in cats the disease targets the lungs. When immature heartworms reach the small arteries in a cat’s lungs, they trigger a severe inflammatory reaction that damages the airways and the tiny air sacs where oxygen exchange happens. The result is coughing, gagging, rapid or labored breathing, vomiting, weight loss, and lethargy. These symptoms overlap so closely with asthma that heartworm disease is frequently misdiagnosed as a breathing allergy.
The harder truth about feline heartworm disease is that it has no safe treatment. The drugs used to kill heartworms in dogs can be fatal to cats. Prevention is the only reliable strategy, which is why monthly heartworm prevention is recommended even for indoor cats (mosquitoes get indoors easily).
Fungal Infections
Less common but worth knowing about, fungal organisms can cause chronic nasal and respiratory symptoms. The most frequent culprit in cats is Cryptococcus neoformans, which typically starts in the nose and sinuses. Affected cats develop nasal swelling, chronic sneezing, and nasal discharge that may become bloody over time. If the infection spreads to the lungs, breathing becomes labored and rapid. Fungal infections tend to progress slowly and don’t respond to the antibiotics used for bacterial infections, so they can go undiagnosed for weeks if a vet isn’t specifically looking for them.
Environmental Irritants Without Asthma
Not every sneezing cat has an infection or asthma. Some cats are simply sensitive to airborne irritants. A new brand of litter, a plug-in air freshener, a heavily scented cleaning product, or even construction dust can trigger bouts of sneezing and mild coughing that stop once the irritant is removed. The pattern is the giveaway: if symptoms started around the same time you introduced something new to the home, try eliminating it for a week and see if the sneezing stops. Switching to a low-dust, unscented litter is one of the easiest first steps.
Signs That Need Urgent Attention
Most mild sneezing episodes aren’t emergencies, but certain signs indicate your cat is in respiratory distress and needs veterinary care right away. Open-mouth breathing in a cat is always abnormal and always urgent. Other red flags include blue-tinged gums, rapid continuous panting, an inability to settle or obvious distress, standing with elbows pushed outward and neck extended, exaggerated chest or belly movements with each breath, and collapse. A resting breathing rate above 35 breaths per minute also signals trouble.
Even without these acute signs, sneezing and coughing that persists beyond 10 to 14 days, gets progressively worse, or is accompanied by loss of appetite, weight loss, or bloody nasal discharge warrants a vet visit. Respiratory panels can test for herpesvirus, calicivirus, Bordetella, Mycoplasma, Chlamydia, and several other pathogens from a single swab, giving your vet a clear picture of what’s driving the symptoms.