Not all Chihuahuas stick their tongues out all the time. In affected specimens, however, there can be different reasons behind it. Sometimes the Chihuahua’s tongue is simply longer than the muzzle. This is a concomitant of the small, round head and is more common in mini Chihuahuas than full-sized Chis.
So the tongue does not fit completely into the oral cavity and as a result, the tongue sticks out a little. Sometimes it’s just the tip, but often you can see quite clearly how the tongue hangs out in front or to the side. By the way, Chihuahuas with a shortened lower jaw should not be used for breeding.
However, there may be other reasons why Chihuahuas stick their tongues out. Unfortunately, the breed often has problems with its teeth. They are lost at a young age or have to be raised later. Now it can happen that the tongue is no longer blocked and held back by the teeth. If teeth are missing, the tongue simply slips out.
On the other hand, the harmless causes of “tongue out” include panting or excitement.