Why Does My Cat Get Mad When I Sneeze?

Right now there is a mean heat wave hitting Europe and Italy where we live, so we have had to use the airconditioner quite often. This has unfortunately led to both me and my fiancé picking up a cold, which means a lot of sneezing. And Freja is non to happy about that.

In fact, she seems to hate it, meowing aggressively almost every time one of us sneezes. If we keep sneezing she might get so offended that she walks away! 

This is not a universal cat pet peeve as our cat Thor, doesn’t react in the slightest when either of us sneezes. A quick search online revealed that there are plenty of other cat owners who have cats that exhibit a similar hate towards their humans sneezing however.

It is difficult to get an exact answer since we can’t ask Freja directly why she reacts the way she does, but we can infer a few things based on feline behavior and off of her reaction.

A cat may get mad when you sneeze because they perceive the noise to be aggressive or threatening. They might think you are scolding them, and as such want to protest this grave injustice, or they might simply be telling you that you should stop with these sudden loud noises, since that is something most cats really do hate.

Other cat owners have written that their cats react with a submissive or almost scared meow to their owners sneeze. Since cats can perceive the meaning of the sounds differently, and humans also sneeze differently, we can theorize that some cats may simply be asking their owner if they are okay, or might be sad because they think they are getting scolded.

But to summarize the most likely reason is that cats are creatures of habit and don’t like loud, sudden noises and or that they may perceive the sneeze as being a form of aggressive behavior / scolding from their owner.

Why Do Cats Open Their Mouth When Smelling?

black and white cat with yellow eyes picking up scent and exhibiting the flehmen response

Cats open their mouth as part of the flehmen response/reaction. The flehmen response is a behavior where the cat elevates their upper lip and opens its mouth for about 5-10 seconds allowing the transfer of pheromones and other scents to the Jacobson’s organ/vomeronasal sensory organ (VNO) located just above the roof of the mouth, behind the teeth in the nasal septum.

The VNO triggers an appropriate behavioral response from the cat when it comes into contact with specific pheromones and scents, like the scent of another cat.

image of black and white cat with yellow eyes picking up scent and exhibiting the flehmen response
close up of a black and white cat picking up a scent on a grey background

When do cats perform the flehmen response?


A cat performs the flehmen response when investigating sites of particular interest to it, odors or tastes. This can help the cat identify the presence of another cat or food.  It also has a variety of other uses: Male cats use it to identify the presence of a female cat in heat, whilst female cats use it to track the whereabouts of their children to name a few examples.

Cats also use the VNO when performing scent rubbing to help distinguish between similar smelling substances before performing the rubbing.

The Flehmen response in other animals

The Flehmen response is also seen in other animals such as dogs, horses, cattle, pigs, goats, big cats, snakes and lizards to name some..Differently from cats, horses and other hoofed animals curl their upper lip and reveals their teeth rather than opening their mouth as cats do.

Snakes also has a similar response when they stick their tongue out to facilitate the transfer of scents by gathering them with the tongue and touching the tongue to the opening of the organ.

What is the Jacobson’s organ / vomeronasal organ?

The Jacobson’s organ was named after the Danish surgeon Ludwig Lewin Jacobson when he rediscovered the organ in the human nose. The organ had first been discovered by Frederick Ruysch prior to 1732. Jacobson announced his findings to the world in 1809. 

Although present in humans, the organ is non-functional. 
The organ got its other name, the vomeronasal organ (VNO for short) from it’s adjacent unpaired bone (the vomer bone in latin) and its location in the nasal septum.