Why Does My Dog Smack His Lips. Why does my dog smack her lips in the middle of the night? As well as seizures, ocd, or dementia.
In the most harmless cases your dog may simply be dreaming about food, causing them to smack their lips during sleep. Dogs may lick their lips when you pet them as a signal that they are nervous or stressed by the behavior. Constant smacking or licking of lips can act as an instinctual calming behavior that helps your dog relax, but it can also signify a poor or irregular diet.