Cats will casually stick their tongues out when relaxed or content. This is normal and not a concern.
To cool down, cats pant with their mouths open and tongues out to promote evaporation. Provide water and shade.
Dental disease like gingivitis can make it uncomfortable for cats to retract their tongues. Seek veterinary care.
Nausea or oral pain can cause a cat to leave its tongue out. Look for other signs like vomiting or appetite issues.
Nerve damage from an injury can paralyze a cat's tongue. See a vet immediately if the tongue hangs to one side.
Severe dehydration may cause a cat's tongue to stick out as they pant and try to increase saliva. Give fluids.
Tumors in the mouth or on the tongue can make it hard for cats to retract their tongues. Seek vet care.