There are many reasons that dogs develop a fear of other animals or people.  The most common is poor socialization, which means that exposure to other animals and people was limited or minimal when the dog was young.  Dogs are very impressionable—after one intense or traumatic experience, many dogs “generalize” their reaction to many similar situations.

Fears can arise in several developmental stages during the first few years.  These fears can slowly become more intense over the years or can suddenly intensify, especially if there has been a particularly unpleasant experience.  However, fears that begin to show up well into the adult or senior years might be related to medical problems that lead to painful conditions, changes in neurologic function, reduced vision or hearing loss, or other illnesses.

Socialization is the key to raising a dog without fearful responses.  Early, frequent, and pleasant encounters with people of all ages and types can help prevent fears later.  In addition, dogs should be exposed to as many different places, sights, and sounds as possible so that they become accustomed to different environments early, before fears emerge.

Dogs that are frightened can show aggression, attempt to run away, fidget, or freeze.  When attempting to avoid a real or perceived threat, a dog may cower, look away, tuck its tail, and perhaps tremble or pant.  At other times, it may only duck its head and look away, tolerating petting at first—but then snapping.  It is important to watch your dog for signs of uneasiness such as backing up, hiding behind you, and licking its lips.  These signs combined with raised hairs on the back (hackles), growling, or snarling, can indicate fear-related aggression.

When interacting with a dog that is exhibiting fear and anxiety, two critical issues must be addressed immediately.  First, with the potential for danger or injury to the dog or others, safety is always the overriding concern.  Your response to the dog is the second important factor.  Threats or punishment are counterproductive, serving only to further aggravate the dog’s fear and anxiety.  To decrease your dog’s fearful responses, you will need to control and train your dog with techniques that calm and settle.  If you find yourself in a situation in which your dog is fearful or anxious and cannot be settled, the best response is to calmly and quickly leave the area.

Usually consultation with a veterinary behaviorist is needed for dogs that are showing extreme fears or aggression.  The cause of the problem needs to be identified, followed by a behavior modification program that has been specifically designed for your dog’s circumstances.  Such programs often include counter-conditioning and desensitization techniques to acclimate the dog to the stimuli that usually cause the fearful response.

Written and reviewed by John A. Bukowski, DVM, MPH, PhD and Susan E. Aiello, DVM, ELS