Canine posttraumatic stress is a diagnosis of exclusion, but an accurate history and specific behavioral and medical signs may indicate that C-PTS may be present. Providers will need to rely on the MWD handler for reporting of a traumatic event exposure and the onset of behavioral signs.

Behavioral signs will vary depending on the personality of the MWD and the perceived intensity of the traumatic event.⁷ They can include any combination of the following: escape or avoidance from work-related environments, increased or decreased reactivity to environmental or social stimuli, positive or negative changes in rapport with the handler, or interference with critical tasks (detection, controlled aggression, and obedience). Medical signs may include any combination of physiological responses to persistent fear, anxiety, or stress. A further description of the potential behavioral and clinical signs is provided Table 1.

NOTE: Possible delayed onset or delayed reporting of clinical signs supporting C-PTS is common, which may then fall into the category of C-PTSD.

Although MWD handlers will most likely seek guidance after acute onset of signs, providers should be aware some MWDs may not manifest obvious signs for some time, or handlers may not seek guidance until the syndrome is advanced. Additionally, some dogs will have been evaluated, and treatment initiated by veterinary personnel, from handlers seeking guidance sometime later. Thus, other keys to C-PTS for providers to be aware of are the continuance of behavioral signs for more than 30 days, resulting in the diagnosis of C-PTSD based on a failure to improve with time or treatment. The behavioral and medical signs are very similar, with the difference being persistence or progression of behavioral signs in addition to the acute versus chronic physiological stress response.