Post-traumatic Stress Disorder (PTSD) is a trauma and stressor-related disorder resulting after an individual has been exposed to a traumatic event, including, but not limited to: death, threatened death, actual or threatened serious injury, or actual or threatened sexual violence either directly or as a witness to these traumatic events. PTSD can also manifest as a result of intense feelings of fear and helplessness. The most common types of trauma resulting in PTSD include sexual assault, military combat, serious accidents, and the unexpected death of a loved one (Reznikov, 2016).

This results in a series of behavioral symptoms, including

– Intrusion symptoms

– Recurrent, involuntary and intrusive recollections of the event

– Flashbacks

– Traumatic nightmares

– Persistent avoidance of stimuli associated with the trauma (e.g. people, places, conversations, activities, objects or situations).

– Negative changes in the way of thinking and mood that are associated with the traumatic event:

– Inability to recall key features of the traumatic event

– Persistent, and often distorted negative beliefs and expectations about oneself or the world

– Persistent distorted blame of self or others for causing the traumatic event or for resulting consequences

– Persistent negative trauma-related emotions (e.g. fear, horror, anger, guilt, or shame) (

– Markedly diminished interest in significant activities that were previously enjoyed.

– Feeling alienated from others (e.g. detachment or estrangement)

– Constricted affect: persistent inability to experience positive emotions.

– Alterations in arousal and reactivity that are associated with the traumatic event

– Irritable or aggressive behavior

– Self-destructive or reckless behavior

– Hypervigilance – Exaggerated startle response

– Problems in concentration – Sleep disturbance

(American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.))

In 2008, the RAND Corporation, Center for Military Health Policy Research, published a population-based study that examined the prevalence of PTSD among previously deployed Operation Enduring Freedom and Operation Iraqi Freedom (Afghanistan and Iraq) service members (Tanielian et al., 2008). PTSD was assessed using the PCL, as in the Gulf War Veterans study. Among the 1,938 participants, the prevalence of current PTSD was 13.8% (US Department of Veterans Affairs).

The endocannabinoid system has been identified as key player in the adaptation to stress. Interactions between endocannabinoids and other physiological systems have been shown to be necessary for regulating emotional memories, which may suggest that the endocannabinoid system is involved in the development and treatment of PTSD. A research group examined this and found that circulating endocannabinoids were significantly reduced among individuals meeting diagnostic criteria for PTSD (Hill et al., 2013). This may be why supplementing exogenous cannabinoids helps to alleviate the symptoms of PTSD.

A recent retrospective study in civilian patients with PTSD patients (Greer, Grob, & Halberstadt, 2014), and a case study in a patient with severe sexual abuse-related PTSD (Passie, Emrich, Karst, Brandt, & Halpern, 2012) showed that consistent cannabis use significantly reduces PTSD symptoms. In addition, a clinical trial is currently being run with 76 Veterans with chronic, treatment-resistant PTSD to determine the therapeutic utility of the whole cannabis plant.