During the Vietnam War, U.S. soldiers often smoked Southeast Asian cannabis to deal with the horrors of combat. After returning home from the war, many veterans continued to use cannabis to deal with the post-traumatic stress of their experience in Vietnam.142 Data from the National Comorbidity Study demonstrated that adults suffering from PTSD were three times more likely to have cannabis dependence as compared with those without PTSD.143 Recent research underscores a strong connection between the endocannabinoid system and how the brain processes traumatic memories.

In 2012, a petition with over 8,000 signatures from a veterans’ group was submitted to the White House asking to legalize the use of cannabis for PTSD. The director of the Office of National Drug Control Policy denied the petition. Yet just one year earlier, on April 28, 2011, the U.S. Food and Drug Administration accepted a protocol design from the Multidisciplinary Association for Psychedelic Studies for their study of cannabis as a treatment for symptoms of PTSD in war veterans.