Many a dog owner has come home to find her couch cushions turned into piles of fluff or her favorite pair of shoes no longer wearable. Unwanted chewing is a common problem in pet dogs -- but chewing on inedible items is a natural behavior for dogs. They have to be taught what they can and can't sink their teeth into around the home.
Normal Chewing Behaviors
It's perfectly natural for both adult dogs and puppies to want to chew, sometimes for several hours a day. It helps to keep their teeth clean and plaque-free, and it strengthens their jaw muscles. Puppies use their mouths to explore the world around them -- and chewing generally relieves soreness in their gums when they're teething. Provide a range of chew toys for your canine friends so they can safely and appropriately fulfill their urge to chew.
Destructive Chewing Behaviors
The problem comes when your dog engages in destructive behavior, chewing objects that he shouldn't be chewing. In an adult dog, this is usually due to anxiety or fear, or is a result of not being taught at an earlier age what he is and isn't allowed to chew. A common cause of stress chewing is separation anxiety, but it's also prevalent in dogs who've had a traumatic past.
What to Do
If your dog chews due to anxiety or fear, you may have to consult a dog behavior specialist to work through his issues. Training the dog the "leave it" command will teach the dog what to drop or leave alone, and may have some residual effect, but that won't necessarily guarantee the dog won't eat your belongings when he's home alone. Take ownership of your belongings, making sure not to leave anything in reach of your dog that you don't want to get chewed. You can also leave lots of chew toys around the house for when the urge strikes him, but make sure they're easy to tell apart from regular household items so he doesn't get confused. Play toy-based games with him often so he becomes more interested in them and prefers to chew them over other items. Make sure he gets plenty of physical and mental exercise and that he's not hungry.
What Not to Do
It's important not to punish your dog verbally after the fact. If you punish him for destroying an item he's chewed even a couple of minutes ago, he won't connect what he has done with his punishment. You should never punish your dog physically under any circumstances. Not only is it cruel, it will make him more fearful, which can lead to escalating behavioral issues. If you catch him in the act, a firm "no" or "leave it" will do, assuming the dog knows the command, followed by a treat or praise for dropping the item. You can then redirect his attention to something he is allowed to chew.