Is Aggression a Training Problem?

When a dog growls, snaps, or shows aggression, it’s often labeled as a training problem or a behavior issue. But behavior does not happen in isolation. A dog’s physical health plays a critical role in how they feel, cope, and respond to the world around them.

In many cases, aggression is not a personality trait; it’s a symptom. Dogs experiencing discomfort, pain, or chronic illness may use aggression as a way to cope when their tolerance is reduced and their stress levels are high.

Behavior Is a Reflection of How a Dog Feels

Dogs communicate through behavior. When they are uncomfortable or unwell, they don’t tell us with words; they tell us by avoiding, freezing, growling, snapping, or biting. These behaviors are often attempts to create distance or stop an interaction that feels overwhelming or even painful. Medical issues can significantly lower a dog’s stress threshold, making reactions faster, stronger, and more difficult to predict.

Chronic Itching and Skin Conditions

Conditions such as canine atopic dermatitis cause persistent itching, inflammation, and often secondary infections. Chronic itch is not just irritating; it is exhausting and stressful.

Dogs dealing with an ongoing itch may:

• Become irritable or reactive

• Show aggression during handling or grooming

• Have difficulty settling or sleeping

• Struggle with focus and learning

When a dog’s nervous system is constantly activated by discomfort, even minor stressors can push them past their coping ability.

Pain and Its Impact on Aggression

Pain is one of the most common contributors to aggressive behavior. This includes:

• Joint pain and arthritis

• Soft tissue injuries

• Back or neck pain

• Undiagnosed chronic pain

A dog in pain may react aggressively when touched, approached, or asked to perform physical movements that hurt. What appears to be “disobedience” or "being stubborn" may actually be self-protection. Importantly, pain-related aggression can occur even when the pain is not obvious or constant. Sometimes, the fear of pain is worse than the pain itself.

Gastrointestinal Upset and Emotional Regulation

Chronic gastrointestinal (GI) issues such as food sensitivities, inflammatory bowel disease, or persistent nausea can affect behavior in significant ways. The gut and brain are closely connected, and ongoing GI discomfort can impact mood, stress tolerance, and emotional stability. Do you feel right when you are nauseated? Probably not.

Dogs experiencing GI upset may:

• Be more anxious or reactive

• Have difficulty focusing during training

• Show irritability around people or other animals

A dog who feels unwell internally may have little capacity left to manage environmental stressors.

Joint and Mobility Issues

Joint pain and reduced mobility can make dogs feel vulnerable. When movement hurts, dogs may guard their space more closely or react defensively if they fear being bumped, touched, or forced to move. This is especially common in aging dogs, such as those with arthritis, but it can occur at any age. 

Dental Disease: A Commonly Missed Cause

Dental pain is often overlooked, yet it can be severe. Infected teeth, abscesses, and gum disease can cause constant discomfort.  

Dogs with dental pain may:

• Resist handling of the head or face

• Snap when leashes, collars, or hands come near their mouth

• Avoid food or chew toys

• Show sudden changes in temperament

Because dental issues are hidden, behavior changes may be the first visible sign.

Why Training and Medical Care Go Together

The most successful training happens when your dog’s health is supported at the same time. Medical treatment helps your dog feel more comfortable in their body, while training focuses on teaching skills, building confidence, and creating safer ways to cope with the world. When dogs are in pain or discomfort, learning is harder, and reactions can come faster. Supporting both health and behavior gives your dog the best chance to feel better and to do better. This is one reason why we send Behavior Consultation Reports to your team of Professionals, including your veterinarian.

What Pet Parents Should Do

If your dog shows new or escalating aggression:

1. Schedule a veterinary evaluation to rule out pain or illness.

2. Schedule a Behavior Consultation to de-escalate the behaviors and keep everyone safe.

Aggression Is Often a Cry for Help

Aggression does not mean a dog is bad or beyond help. It often means the dog is struggling, whether it is physically, emotionally, or both. By looking at behavior through both a medical and a behavioral lens, we can address the root causes and create safer, more effective paths forward for both dogs and their humans. When dogs feel better in their bodies, they are far better equipped to learn, cope, and respond well to training.

"I DO NOT feel well. BACK OFF!"