Dogs and cats use sneezing as a social signal to communicate playfulness and excitement.

In canine behavior, the 'play sneeze' is a well-documented form of meta-communication first popularized by ethologists like Marc Bekoff in the late 20th century. This involuntary reflex occurs when a dog is highly aroused but in a non-threatening way. It serves as a calming signal to playmates, ensuring that rough-and-tumble play does not escalate into a real fight.The physical mechanism involves the dog wrinkling its nose and taking short, sharp breaths, which triggers the sneeze reflex. This behavior is most common in breeds with shorter muzzles, though it is seen across the species. By sneezing, the dog effectively 'resets' the mood of the interaction, confirming that their bared teeth or pounces are just part of the game.For cats, sneezing is more frequently tied to physical irritants, but feline behaviorists note that it can occur during moments of intense displacement activity. When a cat is conflicted or over-excited, the nervous system may trigger a sneeze as a physical release of tension. This is often observed during vigorous play sessions or when a cat is anticipating a high-value reward like a treat.While social sneezing is normal, veterinary experts at institutions like the Cornell Feline Health Center warn that persistent sneezing can signal feline herpesvirus or calicivirus. If sneezing is accompanied by discharge or lethargy, it usually indicates a medical issue rather than a social one. Understanding these subtle cues helps pet owners better interpret their animals' emotional states and health needs.