When to see a vet urgently
Go to an emergency vet immediately if your cat has any of the following respiratory signs:
- breathing with the mouth open
- bluish gums or tongue
- clearly laboured breathing even at rest, with pronounced abdominal effort
- inability to settle and rest because of breathing difficulty
Do not wait for coughing or a change in mucous membrane colour. Find an emergency vet near you and contact them.
Overview
Feline asthma is chronic inflammation of the lower airways. In response to triggers, bronchial walls thicken, their diameter narrows and mucus accumulates inside. This makes breathing difficult and can cause severe breathlessness. Veterinary references, including the Merck Veterinary Manual and MSD Veterinary Manual, classify feline asthma as an immune-allergic disease in which hypersensitivity and inflammation are central.
Contraction of smooth muscle around the bronchi can narrow the airways quickly. Concurrent swelling and mucus further obstruct airflow. Breathing out can be particularly difficult, leaving air trapped in the lungs. Long-term inflammation can change airway structure, so asthma treatment addresses more than muscle contraction during a visible attack.
Asthma and chronic bronchitis can look similar to you. The tendency towards bronchial constriction characteristic of asthma distinguishes it from chronic bronchitis. Cats' inflammatory responses also have species-specific features: serotonin, for example, plays a part in bronchial constriction. Treatment experience in people or dogs therefore cannot be applied unchanged to cats.
Causes
Several factors can contribute to the onset of asthma, often together:
- Environmental allergens: house dust, mould, pollen and tobacco smoke.
- Irritants: air fresheners, household chemicals and deodorants.
- Infections: previous viral or bacterial infections can trigger chronic inflammation.
- Inherited susceptibility: asthma is more common in Siamese cats, for example.
A trigger is not always the same as the original cause of disease. In many cats, no single allergen can be identified. Infections and lung parasites can also cause signs resembling asthma, so a previous respiratory infection alone does not establish that a current cough is asthma.
Risk factors
- Age 2–8 years, the most common age group at diagnosis.
- Poorly ventilated spaces or abundant dust.
- Chronic respiratory diseases.
- Breed susceptibility, particularly in Oriental breeds.
- Stress, which can worsen symptoms.
Information about risk factors in cats is limited, and breed associations do not establish a clear mode of inheritance. Asthma also occurs in other breeds and at different ages. The age range above describes a common age at diagnosis; being outside it does not rule out disease.
Symptoms
You may notice:
- Repeated coughing that resembles attempts to vomit.
- Difficulty breathing, sometimes with the mouth open.
- Wheezing or rattling breath sounds.
- Lethargy and reduced activity, particularly after an attack.
- Bluish mucous membranes during a severe flare-up.
Note: coughing is not normal in cats and always needs investigation.
When coughing, a cat may crouch close to the floor and extend its head and neck forwards. The movement sometimes looks like an attempt to vomit a hairball, although nothing comes out. A safely recorded video helps your vet distinguish coughing, gagging and vomiting. Recording must not delay treatment of breathing difficulty.
Normal appetite or bright behaviour between attacks does not rule out asthma. The loudness of wheezing alone also cannot establish that a situation is safe. Record coughing episodes and any possible connection with cleaning, changing litter or using scented products, for example.
Possible complications
Without timely treatment, asthma can lead to:
- chronic respiratory failure
- oxygen deprivation, or hypoxia
- permanent lung changes
- sudden life-threatening attacks
However, breathing difficulty does not automatically mean an asthma attack, even in a cat with a previous asthma diagnosis. Heart failure and fluid accumulating around the lungs, for example, can also impair breathing. Their treatment differs from that for bronchial narrowing, so clearly abnormal breathing is not assessed at home solely on a previous diagnosis.
Diagnosis at the vet
Only a vet can make an accurate diagnosis. Investigations usually include:
- taking a history about living conditions and symptom frequency
- listening to the lungs
- chest X-rays
- blood tests and tests to exclude infections and parasites
- bronchoscopy where necessary
There is no single test that reliably establishes asthma. X-rays may show prominent bronchial markings and overinflated lungs, but not every asthmatic cat has typical changes. Imaging also helps look for other causes. Increased blood eosinophils, a type of inflammatory cell, can support suspicion, but similar findings can be associated with parasites.
Bronchoscopy means looking inside the airways with a scope. During it or separately, a lavage sample can be taken to examine inflammatory cells and culture microbes where necessary. The investigation usually requires sedation or anaesthesia. A cat struggling to breathe is stabilised before unnecessarily stressful investigations; an acute situation may require hospital care and supplemental oxygen.
Lungworms can be sought with an appropriate faecal test. Other infection investigations are selected according to history and exposure. Treatment response contributes to the overall assessment, but temporary relief alone does not replace investigation of other respiratory diseases.
Treatment
- Corticosteroids, or glucocorticoids, are the mainstay: initially as tablets or injections, then by inhalation through a spacer with a feline mask, using fluticasone for example. Most cats adapt quickly.
- An inhaled bronchodilator such as salbutamol relieves an attack but does not replace corticosteroids: without them, bronchial inflammation continues.
- Remove household irritants, including tobacco smoke, dusty cat litter, sprays, fragrances and incense.
- Weight loss in an overweight cat makes breathing easier.
The sequence of medicine formulations is not the same for every cat: your vet chooses initial and ongoing treatment according to symptoms, other diseases and how successfully medicine can be given. A bronchodilator relieves constriction but does not control asthmatic inflammation on its own. Do not decide on rescue medication needs or use by changing maintenance treatment yourself.
Long-term systemic corticosteroid treatment can have adverse effects, including increased diabetes risk. Inhalation directs medicine to the airways and reduces exposure elsewhere in the body. Report increased drinking or urination to the treating vet. Suspected side effects are addressed by reviewing treatment because a sudden unsupervised change can worsen asthma control.
Practising inhalation and monitoring at home
Introduce the mask in a calm situation when your cat's breathing is stable. Initially, your cat can become familiar with the device without medicine and associate it with a positive experience. Your vet demonstrates how the mask fits snugly over the nose and mouth and how to check breathing through the spacer. Review the device instructions and prescribed medicine together.
Also monitor the doses remaining in the inhaler so it does not run out unnoticed. Observe breathing while your cat sleeps: record breaths per minute and changes from your cat's usual level. Repeated increases or greater breathing effort require contact with the clinic. A quieter period alone is not a reason to stop medicine without agreed instructions.
When to see a vet
Open-mouth breathing, bluish gums or tongue, and rapid, laboured breathing at rest are emergencies in a cat. Do not wait for them to pass: take your cat to a clinic in a carrier and try not to frighten it.
Avoid unnecessary handling during breathing difficulty. Tell the emergency clinic about respiratory symptoms and current medicines when first making contact. If your cat has an individual flare-up plan, follow it while arranging help. Learning a new medicine or device during an attack must not delay departure.
Prevention
Although asthma cannot be prevented completely, you can reduce the risk of flare-ups:
- clean away dust regularly
- avoid aerosols and strong cleaning products
- do not smoke near your cat
- use hypoallergenic cat litter
- maintain a normal weight and good general condition
A hypoallergenic label alone does not indicate whether litter is dusty or fragrance-free. The aim is to reduce dust and scents that irritate breathing. Recording environmental changes alongside symptoms can help reveal a possible connection. Reducing irritants supports treatment but does not replace medication for inflammation.
Prognosis
Many cats with asthma can live active lives when symptoms are controlled and flare-ups recognised. However, a symptom-free period does not mean the condition is permanently cured. Follow-up assesses both recurring signs and treatment suitability. The aim is to prevent further severe attacks and maintain the best possible breathing function.
This text provides general information and does not replace veterinary care. Contact a vet if your cat develops symptoms.
Frequently asked questions
Can a movement that looks like vomiting a hairball actually be coughing?
Yes. An asthmatic cat may crouch and stretch its neck while coughing without producing a hairball. Do not leave a repeated symptom uninvestigated on the assumption that it is an ordinary hairball problem. A video can help identify it.
Can a cat have asthma even if chest X-rays look normal?
Yes. Not every cat with asthma has typical X-ray changes. Diagnosis combines symptom history, examination findings and exclusion of other diseases, sometimes also using airway samples.
Can asthma medicine be stopped when coughing ends?
Change medication only as agreed with your vet. Symptoms improving may show that treatment works even though the tendency to inflammation remains. Many cats need long-term treatment, and a bronchodilator alone does not replace inflammation control.
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
Sources
- Feline Asthma: What You Need To Know, Cornell University, accessed 2026-11-03.
- Feline Bronchial Asthma, Merck Veterinary Manual, accessed 2026-11-03.
- Asthma and Bronchitis in Cats, VCA, accessed 2026-11-03.
- Feline Asthma: A Risky Business for Many Cats, Cornell University, accessed 2026-11-03.
- Treatment Instructions for Asthma and Bronchitis in Cats, VCA, accessed 2026-11-03.
- Species Approach to Inflammatory Airway Disease in Animals, Merck Veterinary Manual, accessed 2026-11-03.
- Dyspnea (Difficulty Breathing), Cornell University, accessed 2026-11-03.