Why Does My Cat’s Mouth Hang Open?

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Our lovely feline friends seldom make any noise with their mouths because they are so intelligent. When a cat suddenly opens its lips for what seems to be no reason at all, it is a sight that could raise anxiety in an attentive owner, and there are times when that fear is legitimate. What gives the impression that Kitty’s mouth has been left unlatched? Your pet may be displaying a pattern of behavior known as “the Flehmen reaction,” which is not harmful, but if it continues, you should take them to the vet as soon as possible. Let us get together and discuss the many different options that are offered in this article.


In general, cats breathe via their noses rather than their mouths. When a cat opens its mouth, it is often for a specific reason, such as eating, drinking, grooming, or generating vocalizations. Cats also sometimes purr when they open their mouths. Or even more drastic actions, such as biting the hand of the person who is irritating you or nibbling on anything. Because we are sentient beings, we can understand all of these ideas with reasonable ease.


The Flehmen reaction is just one more reason why a cat could be sitting there with its jaws hanging open, but this one does not pose any health risks and just happens naturally.


What’s the Flehmen reaction?

It is referred to as the Flehmen reaction or the Flehmen response, and it is a peculiar behavior that is shown by just a few species of animals, such as cats. When a cat comes across a fragrance that piques its interest, it will sometimes spread its lips wider to take a fuller, more in-depth whiff of the odor. The feline has a particular organ that is often referred to as Jacobson’s organ or the vomeronasal organ. This organ gives the cat the ability to analyze the air that it breathes in via its mouth.


The Jacobson’s organ of the cat is located in the upper jaw, right above the palate in the mouth of the cat, and is often referred to as the Jacobson’s gland. The sample of air is brought into this specific organ through a very minute route, and the cat is then in a position to analyze it.


Your cat has a sense that may be described as being somewhat similar to a combination of its sense of smell and its sense of taste. You can really “taste” and “smell” things via the mouth of the Kitty if you want to!


How does it seem when cats have the Flehman reaction?

A cat investigates the source of a strange odor and finds that it fascinates it. After giving it a good, long smell, they will often stop for a while, slightly open the corners of their lips, and reflect for a few seconds on what they have just experienced after giving it a nice, long scent. After this, there is often a unique expression that can be observed on the face of the target. Some owners take it to mean, “Ewwww, what is that aroma!” and this is how they interpret it. It is also possible to find it interesting to watch, especially when it is brought on by one cat sniffing the rear end of another cat.


When does the Flehmen reaction occur?

According to the consensus among scientists, the Flehmen reaction is triggered by a series of specific pheromones. [Citation needed] Pheromones are chemical signals that plants and animals use to communicate with one another in a manner that is neither loud nor obvious. Pheromones can only be detected by other organisms that can detect them.


Pheromones are chemical signals that are emitted by cats and conveyed by air. Pheromones let cats communicate with one another. It is possible to tell from these signals whether or not a cat is dominant and aggressive, as well as whether or not it is sexually available. The fact that a response was sent indicates that whatever it was that was delivered must have included some highly interesting information.


It is well knowledge that certain types of animals are capable of responding to the pheromones that are generated by other kinds of animals. No one knows for certain if there is a complex communication system across species or whether these pheromones are just too similar to one another and perplexing for anybody to differentiate between them. It is a well-established fact that domestic cats often respond to the pheromones left behind by other animals, including dogs and even humans.


Is there any possible cause for my cat’s jaw to be hanging open like this?

The Flehmen reaction is entirely risk-free, and it even has the potential to be enjoyable to watch at times. There are, however, several distinct scenarios in which a cat may walk about with its mouth wide open. Some cats seem to forget about themselves for a fraction of a second or two when they are grooming and instead fix their attention on something else while their lips are just slightly open. They may even keep their jaws closed but leave their tongues hanging out of the space between their teeth!


Several different medical issues might result in a cat’s mouth being left open and dangling off to the side.

If you notice that your cat is breathing via its mouth and that it keeps its mouth open for more than a few seconds at a time, this might be a sign that he or she is enduring some kind of health problem.


If a cat is suffering from any one of several different medical conditions, its nose may become partially or blocked, forcing the animal to breathe via its mouth instead of its nose. The following constitutes each of these prerequisites:


A bacterial or viral infection


Tumors in the nasal cavity


In other situations, the cat’s nose is OK, but its mouth is experiencing some kind of pain. Stomatitis and gingivitis are both unpleasant conditions that may damage a cat’s mouth. Stomatitis is more common. Stomatitis is a more serious form of gingivitis than gingivitis.


If you notice that your cat keeps its lips open for no apparent reason, you should bring this up with your pet’s veterinarian as soon as possible. Mention any other symptoms that may serve as a signal that there is a problem, in particular, the following:


Swelling in or around the face

Loss of appetite


Lethargy or excessive sleeping

Any change in the cat’s behavior patterns


What should you do if you notice that your cat is breathing heavily?

If your cat is wheezing, it is a sign that it is having trouble breathing and should be sent to the vet. A cat can exhibit this behavior when they are experiencing a substantial amount of mental or emotional stress; but, it may also be a symptom of more major health concerns. You may see the following:


Panting and difficulty breathing

Lowered head with elbows pulled away from the body

Apathy and refusing to move



A blue color might be seen in the gums (indicating low levels of blood oxygen)

All of these signs point to the fact that your cat is having a lot of problems breathing and may need more oxygen at this very moment. Maintain your calm and do all in your power to prevent the cat from becoming nervous, as this might make an already difficult situation a great deal more so. Put the cat in the carrier with caution, and then take it to the veterinarian as quickly as you can.


What might be causing cats to breathe so quickly in this manner?

It is quite improbable that you would ever come across a case of acute respiratory distress in a cat because this ailment is so rare. Some of the most frequent reasons are as follows:

Cats are prone to developing cardiac conditions, one of which is the accumulation of fluid in the lungs.

Any condition that affects the lungs


The chest of the cat has been injured in some way.

Your cat may have a condition known as Feline Infectious Peritonitis or FIP for short. This condition may lead to fluid accumulation in the belly and chest, which prevents the lungs from expanding as they normally would.


Maintain a state of constant readiness in the event of a medical emergency, and if one does arise, be aware of where you may seek aid. In the case that your veterinarian does not provide service around the clock, you should inquire with them in advance about who you should get in touch with in the event of an urgent situation. Get your pet ready for the trip to the vet by getting them into a carrier and deciding how you will take them there.


You do not seem to have any comprehension as to the reason why your cat’s mouth is drooping open, do you?

Put this book down right away and contact your veterinarian to schedule an appointment if any of the signs or symptoms of a medical illness have shown themselves to you.


In any other circumstance, be sure to get in touch with us! You should make an effort to record a video of your cat while he or she is exhibiting the Flehmen response, and then you should upload the video to an online community that is dedicated to cats. Other cat owners in the community may be able to identify the condition as a Flehmen reaction, or they may offer an alternative explanation.

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