Catster is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

My Cat Is Breathing With Their Mouth Open, What’s Wrong? (Vet Answer)

Written by: Dr. Marti Dudley, DVM (Vet)

Last Updated on February 23, 2024 by Catster Editorial Team

burmese cat catching breath

My Cat Is Breathing With Their Mouth Open, What’s Wrong? (Vet Answer)


Dr. Marti Dudley Photo


Dr. Marti Dudley

Veterinarian, DVM

The information is current and up-to-date in accordance with the latest veterinarian research.

Learn more »

Although panting is a common occurrence in dogs, it is significantly less common in cats and can be a sign of ailment. Prolonged periods of panting or open-mouth breathing in cats are considered abnormal and warrant a timely visit to your veterinarian. Causes of open-mouth breathing can be linked to disease of the heart and lungs, infection, trauma, blood loss, and foreign bodies.

Below are some of the more common reasons for open-mouth breathing, but it is important to note that there are other causes as well. Continue reading to learn why your cat may be experiencing open-mouth breathing and how to approach this potential emergency.

cat + line divider

Normal Causes of Open-Mouth Breathing

Cats can occasionally experience short periods of panting or open-mouth breathing. However, panting should reside once the stimulus has resolved that initially caused the panting, whether that is heat, exercise, or stress. In situations where panting does not quickly resolve, veterinary care should be pursued.


Acute situations causing stress can lead to open-mouth breathing. This can occur commonly to cats during car rides. It is important that a cat that is open-mouth breathing quickly recovers once they have been removed from the stressful situation.

young cat breathing heavily
Image Credit: Zhuravlev Andrey, Shutterstock


Young, active cats who dart quickly around the house may intermittently pant. This can be a normal response to heavy exercise. If this is noted, play should be interrupted, and the cat should be allowed to calm down. At rest, the breathing pattern should quickly return to normal.

Temperature Regulation

In extreme heat, cats may pant to expel heat. If this is noted, cats should be moved indoors and cooled with a fan. A veterinarian should be contacted, as your companion may be experiencing heat stroke, which could be deadly.

Flehmen Response

One common reason you may see your cat with their mouth open is due to the flehmen response. The flehmen response is a way a cat gathers information regarding their environment through pheromones that cross over the vomeronasal gland, which is located at the base of the nasal cavity. The flehmen response occurs quickly and is not persistent but can resemble open-mouth breathing.

cat + line divider

Problematic Open-Mouth Breathing

Great care should be taken toward cats with prolonged or reocurring bouts of open-mouth breathing or panting. Abnormal breathing is often a sign of significant illness in our feline companions and should be treated as an emergency. If the ease of your cat’s breathing ever comes into question, it is safest to seek the opinion and care of a veterinarian.

Fluid Accumulation

Fluid accumulation in the chest or abdominal cavity can lead to labored breathing. This is due to the inability of the lungs to properly expand as a result of fluid gathering either around the lungs or within the belly. Fluid can accumulate due to infection, heart failure, neoplasia, and trauma, among other reasons.

Cats suffering from fluid accumulation will experience open-mouth breathing and abdominal effort associated with their breaths. Initial treatment requires oxygen supplementation and the potential removal of fluid.

vet checking the tabby cat in vet clinic
Image Credit: Andy Gin, Shutterstock


Tumors can occur within the chest and impact the lungs, leading to difficulty breathing. Diagnosing tumors often involves radiographs and possibly ultrasounds, and it’s best to get your cat in to see the vet so they can make a proper diagnosis.


On occasion, a significant upper respiratory infection (URI) may occlude the nostrils. As a result, cats may be seen open-mouth breathing. Further, if infection settles lower in the lungs, leading to pneumonia, cats may experience labored breathing as well. Generally, however, URIs are not severe and do not cause breathing problems.


One of the most common respiratory diseases cats face is asthma. Asthma is essentially an allergic reaction to an inhaled irritant that results in lower airway signs. Asthma can slowly develop, or it can be acute and sometimes very severe.

Asthma is diagnosed from history, clinical signs, and thoracic radiographs. Asthmatic cats may cough, wheeze, and experience labored breathing. Fortunately, cats with asthma can improve with appropriate treatment, which typically involves steroid administration.

cat + line divider

When Should I Seek Veterinary Care?

You should seek veterinary care if abnormal breathing is prolonged or recurring in your cat. A cat at rest and in a comfortable environment should not be seen open-mouth breathing or panting. If panting seems to be inappropriate, evaluation of the cat’s environment and health is imperative.

On average, cats at rest breathe 30 breaths or less per minute. If this number is consistently elevated, or if your cat is struggling to breathe, an appointment should be scheduled with your veterinarian as soon as possible.

Signs of difficulty breathing include:
  • Open-mouth breathing/panting
  • Abdominal effort with breaths
  • Mucus membranes are blue or cyanotic
  • Quick breaths
  • Shallow breaths
  • Coughing
  • Outstretched neck

Transporting a Cat in Respiratory Distress

If you need to seek veterinary care and your cat is having difficulties breathing, you first need to call your veterinarian. Calling ahead will allow your veterinarian a chance to gather the necessary supplies to support your cat in an emergency. In an emergency, it may be in the best interest of your cat to go to the nearest veterinary hospital to minimize the stress of travel and quicken the speed at which care can be administered.

Try not to physically hold your cat, as this may cause them to panic further. Instead, place your feline companion in a carrier that is large enough for them to comfortably lay or stand. Try to keep the temperature in the car cool but comfortable. Many cats like being able to hide in stressful situations, like during a car ride. In a cat with respiratory distress, placing a breathable blanket or towel over a carrier is preferable to having your cat burrow underneath a blanket.

a cat in a travel carrier
Image Credit: Nils Jacobi, Shutterstock

cat + line divider

In Summary

Panting or open-mouth breathing may be a sign of respiratory distress in cats. If the abnormal breathing seems out of place, is prolonged, or is recurring, veterinary care should be quickly sought. There are several different causes for open-mouth breathing, and often, diagnostics will be necessary to determine the underlying cause.

Unfortunately, the prognosis in cats experiencing abnormal breathing is varied, as prognosis is dependent on the underlying cause and the response to medical intervention. When in doubt, seek veterinary care if your cat exhibits signs of abnormal breathing.

Featured Image Credit: Yuttana Joe, Shutterstock

Get Catster in your inbox!

Stay informed! Get tips and exclusive deals.
Catster Editors Choice Badge
Shopping Cart


© Pangolia Pte. Ltd. All rights reserved.