Potential Medical Issues Causing Behavior Change in Your Dog

Undiagnosed or untreated medical conditions can have a huge impact on your dog’s behavior and is often responsible for sudden changes in irritability and aggression. If the cause of behavior change is medical, training exercises and behavior modification will NOT be successful.

Here is a list of potential underlying medical conditions and symptoms that can impact your dog’s behavior.

Pain or Discomfort:

  • Gastrointestinal issues
  • Wounds
  • Injuries
  • Recent Surgeries
  • Recovering from a medical procedure
  • Hip-dysplasia
  • Arthritis (joint pain or limping)
  • Back injuries
  • Soft tissue injuries
  • Allergies, extreme skin irritation

Internal Organs:

  • Toxins in bloodstream
  • Increased thirst or urination
  • Urinary Tract Infection
  • Kidney/bladder stones
  • Liver ailments
  • Enlarged spleen
  • Pancreatitis
  • Colitis
  • Heart issues (may result in lethargy)

Neurological Symptoms:

  • Seizures
  • Tremors
  • Brain Tumor
  • Personality Change
  • Light sensitivity

Hormonal Disorders/Variation:

  • Hypothyroidism
  • Cushing’s Disease
  • Addison’s disease
  • Reproductive cycle flucatuion


  • Canine Cognitive Dysfunction
  • Vestibular disease
  • Loss of hearing, vision, or smell
  • Change in sleep cycles
  • Mobility
  • Intervertebral disc disease

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