PTSD attained formal recognition by the psychiatric profession after the Vietnam War. PTSD was formally recognized as a disorder in the DSM in 1980 and psychiatric casualties are now seen in the same light as medical casualties, that is, worthy of diagnosis and treatment.


PTSD is a psychiatric disorder that can develop after the direct, personal experiencing or witnessing of a traumatic event, often life-threatening. The essential characteristic of PTSD is a cluster of symptoms that include:

  • Re-experiencing—intrusive recollections of a traumatic event, often through flashbacks or nightmares,

  • Avoidance or numbing—efforts to avoid anything associated with the trauma and numbing of emotions,

  • Hyperarousal—often manifested by difficulty in sleeping and concentrating and by irritability (APA 2000).

If those symptoms last for a month or less, they might be indicative of acute stress disorder; however, for a diagnosis of PTSD to be made, the symptoms must be present for at least a month and must cause “clinically significant distress and/or impairment in social, occupational, and/or other important areas of functioning” (APA 2000).

Although the onset typically occurs shortly after exposure to a traumatic event, the lag time between exposure and full manifestation of the condition can be variable and in some cases long; if the onset of symptoms occurs more than six months after the trauma it is referred to as delayed onset. Over the long term, PTSD can also be chronic or recurrent (Friedman 2003). In some cases, PTSD occurs alone, but most people who have PTSD also have other psychiatric disorders, such as major depressive disorder (Black et al. 2004; Kessler et al. 1995), that occur either with or after the development of PTSD.

Numerous traumatic events or stressors are known to influence the onset of PTSD; however, not everyone who experiences a traumatic event or stressor will develop PTSD. Its development depends on the

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