A neurotic dog may exhibit chronic anxiety, fear, hyperactivity, obsessive behavior, and inappropriate reactions to stimuli. Truly psychotic dogs, however, are neglected. Their behavior is sharp and unpredictable. It ranges from maniacal highs to deep depression and is usually dangerous and destructive to the dog, as well as to other animals and people the dog is in contact with.

Many of these behavioral characteristics are sometimes manifested by non-psychotic dogs having a « bad day ». Others may be disturbed by some unpleasant illness that temporarily affects their behavior. When the suffering has passed, the behavior returns to normal. The difference between these dogs and truly psychotic animals is that the psychotic animals do not seem to be fully aware of the nature of their destructive behavior. A psychotic dog is not bad behavior; He is simply unable to control his actions.
Dogs suffering from psychosis often experience periods of intense violent rage for no apparent reason. They injure themselves, attack inanimate objects, and attack anyone who is unhappy to embark on their aggressive journey. They often do not respond to external stimuli. Their mood changes rapidly from manic to depressive. Some psychotic dogs do not eat to the extent that they actually die of starvation.

Characteristic behavior of a dog is more likely to be diagnosed as psychotic if one or more of the following conditions exist in the history of the dog: accidental drug overdose, extensive corticosteroid therapy, breakdown before three months of age, serious parasitic infection up to six months of age, severe diarrhea, or head, an extreme psychological trauma.

The pattern of occurrence of psychosis in dogs is quite well parallel to the emergence of psychotic illness in humans. Some dogs have a genetic condition that appears to be destructive early in life. Others lead a normal life until serious psychotic behavior is manifested at a certain age.

Mental health of dogs is of interest and concern to veterinarians. Some specialize in the evaluation and treatment of these mental illnesses, but psychosis in dogs does not enjoy the same level of scientific research that goes into the study of human psychiatric problems. Most owners, though willing to invest significant amounts of money for the treatment of physical ailments with a proven hope for treatment, are reluctant to incur similar costs for the speculative treatment of their dog’s mental illness. Truly psychotic people receive professional psychiatric care in a safe residential facility if needed. Dogs exhibiting serious psychotic behavior are euthanized.