New Horizons Veterinary Behavior Solutions

300 Somonauk St.
Park Forest, IL 60466


are FEARFUL dogs!



Reactive dogs are dogs who wildly pull, lunge, bark, growl, and snap when they see something that triggers arousal in them.  Triggers are often unfamiliar people or unfamiliar animals who they encounter when on a walk, at the park, while they are in the yard, or when strangers enter the home. 


It is important to realize that when a dog reacts this way, he usually does it out of uncertainty, anxiety and fear. In some situations, well socialized dogs may react this way because barriers (tight leashes, fences, enclosed in a car) inhibit their ability to greet and communicate with new unfamiliar dogs or people.  This is referred to as barrier frustration and reactivity escalates as miscommunication continues. 


Rough Guide to the Stress Response in Dogs an explanation to what happens in the brain of a stressed out dog.


Emotion vs. Intellect in the Fearful Dog 


When dog are reactive it is important realize they are in a conflicted emotional state of high arousal and not reacting badly by a conscious choice.  Because this behavior is usually anxiety and fear based, punishment for this behavior will only heighten anxiety and worsen the problem.  


Trigger Stacking can make reactivity and arousal worse and can increase the risk of an aggressive event.



Dogs fear new or novel things for many reasons including their genetics, early developmental deficiencies, lack of positive socialization exposure before 12 weeks of age, and poor previous learning experiences.   Although dominance and pack hierarchy are often discussed as causes of reactivity in the popular media,  dominance is definitely not a cause of dog reactivity and punishment should play no role in changing it. 


Commonly attempted corrections such as leash tightening, jerking, or scolding "No" are ineffective teaching methods for reactive dogs.


To learn more about why Dominance Theory is false and should not be used when working with reactive dogs read Position Statement on the Use of  Dominance Theory and Behavior Modification of Animals from the American Veterinary Society for Animal Behavior (AVSAB). 


Click to download the PDF


And to learn why punishment plays no role in changing reactive behaviors also read the AVSAB Position Statement on the Use of Punishment in Behavior Modification of Animals.

Click to Download the PDF


Before you start working with a reactive dog, a reality check and realistic expectations are important.  To learn more click HERE for a reality check!




Conflict Aggression handout We want to avoid this!




The first step to take to stop reactive behavior is management of the situation.  This means taking the dog out of the situation that triggers the reactivity and avoiding ALL the triggers that start the behavior in the future.  We do not want the reactive dog to continue to practice this high arousal behavior.  The more a dog continues to react, the better he will become at it, until it becomes an ingrained automatic default behavior or habit. The dog can learn that when he reacts, the trigger walks away.  This teaches the dog that his actions are successful and worth repeating.


For some pet owner's avoidance is a satisfactory solution to the problem.  For others, changing their dogs emotional state from fear to joyful anticipation, followed by desensitizing to the triggers; is an important goal they are willing to work toward.  We recommend scheduling a behavior consult appointment with us or a Board Certified Veterinary Behavior Specialist to learn how to modify the anxious dog's behavior through counter conditioning (CC) and desensitization (DS) protocols.  Some dogs with severe reactivity may also benefit from medications.  


We recommend making a list of the dog's triggers, for example: 

  • Tall men
  • Men with beards
  • People with hats  
  • People in Uniforms
  • Children
  • Black dogs
  • Large Dogs
  • Any unfamiliar dog
  • Squirrels and rabbits
  • Cats
  • Things with wheels--strollers, bikes, skateboards, wheelchairs


We also recommend identifying reactivity threshold distances.  Can the reactive dog remain calm three blocks away from the trigger?  How about at two blocks?  Is he going ballistic at one block?   If you can identify the critical distance where arousal begins you can work to keep the dog under threshold.  Staying under threshold will help you manage the problem initially and can also serve as a starting point for future behavior modification training.


The importance of staying below Threshold


Identifying the triggers will help avoid them to manage the problem or until  behavior modification can be done. It may be impossible to remove all triggers (for instance squirrels) but do your best.  For instance avoid public parks, walk late at night, exercise your dog in your own yard.  If barrier frustration is involved avoid allowing your dog unsupervised time outdoors to run the fence line.  Teach your dog to relax away from the door when visitors come.  Avoid high arousal greetings until behavior modification can be done.


Before behavior modification can start the reactive dog will need to learn some foundation behaviors.  To communicate clearly to the dog we recommend using reward marker training or Clicker Training.  Clicker training is easy to do, but also easy to do incorrectly. It is best to working with an educated and experienced trainer such as a Karen Pryor Academy Certified Trainer to learn the mechanics of this wonderful teaching tool. To learn more explore some of the examples on our Clicker Training Webpage



Video: You do not need to use Corrections when working with Reactive Dogs!


EMERGENCY U-TURNS:  How to get out of a problem when an unexpected trigger suddenly appears


This is a very important behavior to have in your tool box and is a variation of “Let’s Go”.  No matter how hard we try to set up a reactive dog for success by working to keep him under threshold as we gradually desensitize him, surprises and accidental encounters will always happen.  So we teach a behavior that will prepare to get him safely out of the situation.


Below is a video that demonstrates a student learning how to teach a loose leash U Turn to a reactive dog:




Trainer and Veterinary Technician Sara Reusche's Reactive Dog Blogs


Eileen Anderson explains Desensitization and Counterconditioning on humans


Video: Desensitization & Counter Conditioning--The details are important  A great lecture on the topic from Veterinary Behaviorist Dr. Chris Pachel, DACVB


Pinterest Video Collection on Counterconditioning and Desensitization 


 C.A.R.E. for Reactive Dogs  the website and Protocol from Jennifer Titus


Managing Triggers Counter Conditioning Response Substitution and Desensitization


Printable Summary Handouts from the CARE Website are below:


A Video Example of Counter Conditioning and Desensitization a dog to a scooter



More Articles and Websites on Reactive Dogs


ASPCA Leash Reactivity


Behavior Modification tips by JulieShaw


Let's Talk Paychecks for Reactive Dogs


Creating a Positive Conditioned Emotional Response.doc


The Practice of Self-Interrruption: The Engage-Disengage Game


Compendium Article on Desensitization and Counterconditioning


Awesome Dogs Shareables Counterconditioning Collection


WDJ Canine Behavioral Anxieties Article  This excellent article by the Whole Dog Journal's Pat Miller has a great explanation on how to counter condition a dog to something that scares him.


Grisha Stewarts BAT website


Podcast: The Challenge of Generalizing Calm Behavior in Reactive Dogs



Training Equipment for Reactive Dogs





We recommend NOT using retractable leashes, choke, prong, or shock collars!




Desensitization & CounterconditioningDesensitization & Counter Conditioning