The most common problem with anxiety in dogs is destructive behavior by the dog when the dog is left alone. There are many reasons a dog may misbehave when left unsupervised and most of them are NOT from anxiety. If your dog ONLY chews destructively or eliminates inside when you are not home, and never makes a mistake any other time, anxiety could be the problem. 

Destructive behavior or house soiling when left alone is NOT spiteful behavior. Don't fall into the trap of thinking your dog KNOWS what she did is wrong because she avoids you when you come home. Slinking around is just canine appeasement behavior. You can prove this to yourself by putting one of your socks on the floor. Now, point to it, put your hands on your hips and start yelling. Appeasement behavior. You know she didn't do anything and so does she. Why is she acting "guilty"? She is appeasing you to avoid conflict. If you are her leader, appeasing you is her job.

When dogs are anxious they feel the urge to eliminate. The more anxious they get, the less likely they are to be able to wait. Additionally, some scent marking that occurs with elimination is reassuring to a dog. So elimination, temporarily, makes the dog feel better. Chewing also makes a dog feel better. It's distracting and helps relieve nervous energy. In fact dogs sometimes chew things that smell the most like you, a chair you sit in, a shoe or your clothing. A reliable indication that destructive behavior is related to anxiety is that the dog, if offered a treat when the owner leaves (good idea), doesn't eat it until the owner comes home. Once the owner arrives, the dog immediately runs to get the treat and wolfs it down. This indicates the dog's level of anxiety when alone is high enough to preclude eating. This is a pretty high level of anxiety which could result in destructive behavior.

If your dog is suffering from separation anxiety he or she probably has experienced one or more of the following past experiences:

	Loss. If a puppy loses his or her mother before 8 weeks of age (if the puppy also lost her littermates anxiety is even more common), anaclitic depression can occur. This "depression" can cause an extreme fear of being alone that results in refusal to eat or relax when alone as well as generalized anxiety or neediness even when you are with her.
	Isolation. Lack of companionship between 8 and 16 weeks of age, such as being caged alone at a pet store or kept in a kennel that does not allow puppies to play together, can contribute to anxiety later in life. Puppies raised without toys or grass and sticks can be afraid of new things and generally insecure.
	Abandonment. If a dog is abandoned by her previous owner, she knows that sometimes people leave forever. Separation is more difficult for these animals.
	Life on the Streets. Stray dogs have to pay attention to everything. Over attention, called hyper-vigilance, is necessary to acquire food and avoid getting attacked or trapped. You may see this expressed as excessive energy or a barking at too many activities that are normal household events.
	Breeding. Some dogs are bred to watch and notice everything so their hyper-vigilance is instinctive and genetic. Sheepdogs, guard dogs and in some cases, sporting dogs inherit this type of obsessive attentiveness. This can make them nervous or easily bored. These breeds are designed to work with a human companion all day. They may not be prepared for hours alone in a working family.
	Schedule Changes. An owner previously at home becomes a full time worker and the dog has no time to adjust to staying alone. When you adopt a dog from the shelter or a rescue organization you can pretty much count on changing her schedule.

TREATING SEPARATION ANXIETY
You can't undo the experiences your dog has already had. That's ok. Dogs are born to learn. If the damage done by your dog is severe enough that you need to confine her to protect her from harm and your house from damage, click the crate link here to read about introducing your dog to a cage properly. A crate will keep your dog from hurting herself or your belongings during a retraining period of two months. However, a crate cannot be used to confine a dog for 8 hours and can't be introduced suddenly. As an alternative, teach your dog using a tie down, described below. 

SEPARATION TRAINING
Make your coming and going rituals less emotional. No long goodbyes and no excited greetings. In fact ignore your dog for 5 minutes before you leave and 5 minutes after you arrive. Try not to jingle the keys and don't rush out of the house with coat and shoes flying. Keep it mellow. You can even help your dog by jingling your keys for no reason throughout the day so this noise is no longer a signal to panic. Don't serve dinner to your dog immediately after you arrive home. This just makes an association between your arrival and hunger and dinner....you don't want to create a need for dinner as well as your company.

When you leave for the day add white noise to your dog's environment, especially for hyper-vigilant dogs or point of access destruction (windows and doorways). You might have success with TV or radio if they are likely to be on when you are home. Tune to the station you listen to or try talk radio.

Even if your dog will not eat when alone, offer her a Kong or Buster Ball stuffed with treats whenever you leave. Put the treat away as soon as you come home--during the ignoring. Your dog needs to learn this special treat is only available while she is alone but you should make it available anonymously and not as a signal that you are leaving.

Hire a dog walker to break up the day. You may also consider doggie day care. It's no joke. The dogs have a great day, make friends, and are tired from a hard day just like you. Great solution for those herding and working breeds. 

The dog must have exercise each day (more is better) in which the he becomes tired (health conditions accounted for). Joining a dog play group at a local park is a fitting activity. A structured activity, like fly ball or agility training is also good. It may surprise you that chasing a ball uphill for 15 minutes is more than enough for your retriever while jogging for 3 miles is not quite enough for your Husky. You may have to be creative finding the right activity that suits your dog and fits your time constraints but with dog powered scooters and skijoring you can do it.

Teach your dog to accept confinement while you are home with a crate or tie down. A tie down is simply a leash that is too short to tangle, anchored to the floor or wall in your home. Attach your dog to the tie down within reach of his comfortable bed. Sit just out of reach and read a book. Reward your dog for lying down, playing with toys or ignoring you by petting him or tossing treats in his direction the instant he is not whining or pulling against the tie down. Once your dog is offering quiet to get the treat, add a phrase that will become a command later, such as "Relax".  Gradually move farther away and then be close again until you are out of view without panicking your dog. Don't use a tie down to confine a dog when you are not home. It's a training aid for correcting behavior and useful when you are home and require the dog to rest quietly. 

You may want to consult with your veterinarian about temporarily medicating your dog. Sedating her is NOT what I recommend. Tranquilizers keep her asleep but do nothing for her state of mind. Valium will make it difficult for her to remember anything so she will not learn that staying home is ok. These types of drugs won't help you in the retraining process. However, there are many medications that may help. Your vet can discuss all your options.