How do I stop my dog from barking all the time?
Barking is a common behavioral problem and is of special concern for people who live close to their neighbors. Barking is a natural behavior, and you should allow your dog to bark in some controlled circumstances.
A dog who barks excessively at the sound of a car in the driveway or the ring of the doorbell may be protecting his territory. While this behavior seems desirable, your dog may not be able to tell friend from foe or know when to curb his aggression, especially if you encourage his watchdog antics. Some dogs are not territorial but simply enjoy the excitement of visitors and bark at them for entertainment.
Let your dog announce the arrival of a visitor, but allow him no more than three barks, then interrupt his barking (by shaking an aluminum can that contains a few pennies, if necessary) and tell him to sit and stay. Reward him with praise or a food treat for proper behavior. Practice having him sit and stay often, even when no one is at the door, until your dog learns to comply.
If your dog barks or howls when left alone inside your home or yard, he may be bored, lonely, distressed at being separated from you or attempting to interact with other dogs in your neighborhood. Be sure he is getting plenty of exercise and attention. Younger dogs (less than three years of age) and dogs whose ancestors were specifically bred to be highly active, such as northern breeds, herding breeds, and sporting breeds, are especially susceptible to boredom. Consider these solutions: buy a dog toy designed specifically to entertain a dog who is left alone; hire someone to take your dog for an energetic walk during your daily absence; or take your dog to a doggy day care center one or more days each week, so he’ll be able to exercise and play to his hearts content.
Several types of antibark (also called bark-control) collars are currently available. Some of them spray citronella (pungent aromatic oil extracted from the Asian grass Cymbopogon nardus), some collars emit a high-pitched noise, and some emit a static shock. These products have variable effects, depending on how they are used, but they do not address the underlying problems that are causing the dog to bark. Likewise, debarking surgery, in which the dogs vocal chords are altered so that he can no longer bark at full volume (although many debarked dogs can still make a significant amount of vocal noise) will not change the dogs behavior.
— Leslie Sinclair, DVM