Is it medical or behavioral?  Both!

If your dog has become easily annoyed, anxious, or reactive don’t just assume that he is being difficult.  Many physical ailments can trigger changes in your dog’s behavior.
Here is a true story from Lisa Radosta DVM, DACVB

(Read the article or listen to the audio track. Don’t miss the videos!)



Waffles, a silver Labradoodle with long eyelashes and a carbon black nose eyes me suspiciously from the other side of the exam room. He came to visit me today because he has for several years lunged and barked at things that pass him on walks. Jules, his pet parent, is loving and attentive. She shares her story with me of the stress to Waffles and to herself dealing with this problem. She has worked with several good trainers and Waffles is not significantly better. As I observe  Waffles I notice that he shifts his weight from one foot to another instead of standing fully on both hind feet. It is clear to me that Waffles has pain in his hind legs. When I shared my suspicion that Waffles was painful, Jules was in disbelief. She reminded me of why she was here. He pulls, lunges, and rears up. He never limps. How could he possibly be painful? It turns out that Waffles was painful, very painful. We took x-rays and found that he had moderate arthritis in both hips. 


Waffles’ case isn’t rare. Matter of fact about 50% of dogs who are brought to veterinary behaviorists have an undiagnosed physical disease. That’s right if your dog has a serious behavior problem, he has a 50% chance of also being sick or painful.  You may be thinking that you know your dog and you would know for certain if he was sick! Even loving attentive pet parents like Jules (and you!) very often have no idea that their dogs are painful or sick. 


As a veterinary behavior specialist, I am often asked how to tell if a dog’s behavior was brought about by a medical or behavioral cause.  It makes sense to want to separate the medical from the behavioral. Placing the problem into a category helps us understand what to do next to help our dogs feel better. Even veterinarians are taught to rule out all medical problems before considering a primary behavioral cause for a pet’s undesirable behavior. However, recent studies have shown that behavioral and medical problems are so closely linked that it can be impossible to separate one from the other as the cause of a behavior problem. 


Behavior problems can contribute to medical problems too. Behaviors like aggression, reactivity, panic, fear, stress, anxiety, frustration, and overexcitement cause a physiological stress response affecting your dog from nose to tail. Your dog’s blood glucose shoots up, his heart beats faster, he starts to pant and his immune system kicks into gear almost immediately in step with the behavior that you see. In the short term, this physiologic response helps your dog to escape from, scare off or cope with what stresses him. In the long term, the build-up of neurochemicals can cause detriment to his health and contribute to physical problems. 


 G.I Issues

Problems such as gastrointestinal upset (diarrhea, vomiting, food intolerance/sensitivity), itchiness (allergies, skin infections), and orthopedic disease (arthritis)  also cause a stress response and inflammation. When physical problems and anxiety, fear, and/or stress are present, the body is overwhelmed. Something’s got to give and often it is the dog’s behavior. 

In this video, Dr. Lisa Radosta, board certified veterinary behaviorist, discusses how physical ailments can affect your dog’s behavior.

Gastrointestinal distress, pain, and discomfort can lead to behavior problems such as fear of the food bowl, taste aversion (refusal to eat certain foods), fear of a certain place in the house, and even fear of the pet parent. Pet parents may perceive that the behavior problem does not have an underlying gastrointestinal cause potentially viewing the pet as stubborn, manipulative, or picky. The gastrointestinal tract and the brain have a magical, unique two-way hotline of communication like no other part of the body. When there is emotional stress, the brain can cause gastrointestinal upset, nausea, hypermotility (food moving too fast through the gut), and decreased appetite. Just as powerfully, when there is disease in the gut, signals are sent to the brain which can contribute to anxiety, stress, and fear. The gut microbiome (bacteria in your dog’s gut) play a role in the production of essential calming neurotransmitters which help to modulate fear, anxiety, aggression, hypervigilance, muscle tension, and stress. The brain and gut are talking to each other minute by minute exchanging information. Matter of fact, the microbiome in your dog’s gut can change significantly within 24 hours of a stressful event!


Skin Maladies

Another player in the physical-emotional game is skin disease. Dogs with allergies to the things in the environment are more likely to show fear, anxiety, and stress, more often engaging in hyperactivity, chewing, mounting, coprophagia, begging for food, stealing food, attention seeking, excitability, and excessive grooming when compared with their non-itchy counterparts.  Think about it, would you be in a sunny mood if you were itchy all the time? The itch-behavior communication flows in the opposite direction too. Dogs with certain types of fears and separation anxiety have been reported to have more incidence of skin disease and more severe skin problems.

Imagine how grouchy you would be if you were dealing with constant itchiness or pain!

 Musculoskeletal Problems

Orthopedic and muscular problems are common contributors to behavior problems with up to 82% of dogs brought to veterinary behaviorists having undiagnosed (their pet parents had no idea!) orthopedic pain. The big misnomer is that dogs who are painful always limp. Not so! Have you ever had pain in your hip, knee, or elbow and no one knew? Do you always cry out or change your body position when you are painful? Of course not. In the same way, dogs don’t always show us when they are painful. Look for signs such as slow to get up or lie down, uneven nail wear, shifting weight onto one leg from the other, splayed toes on alternate feet, and fear or aggression when touched. 


If your dog is showing undesirable behaviors, follow these easy steps:
  1. See your veterinarian and ask for a physical examination. 
  2. Watch your dog closely. Look at old images or pictures of him. Does he move differently? Is he less muscular? If so, talk to your veterinarian about pain. You may not be able to assess your dog without x-rays so don’t forget to ask about those. 
  3. Think about his eating, urination, defecation, and sleeping habits; have they changed? If so, he may have an endocrine or gastrointestinal disease. Ask your vet for baseline labwork. 
  4. Is he licking himself? Most likely he is itchy. Talk to your vet about an evaluation of the skin. 


Behaviors are physical and physical problems contribute to behaviors.  They are inseparable. You are your dog’s best advocate. If your dog is acting differently, turn every stone over until you find the causes. Are you wondering what happened to Waffles? After 2 weeks of treatment with pain medication, Waffles’ behavior is 90% better. True story.


[Editor’s note: If your dog is still showing signs like Waffles’ of stress or aggression on walks, register for our online course, Your Reactive Dog: From Anxious to Zensational.]