Post-traumatic stress disorder (PTSD) is a mental problem that develops after experiencing or witnessing a traumatic event. PTSD sufferers experience flashbacks, severe anxiety attacks, nightmares and uncontrollable thoughts associated with the event. These people often feel stressed and in danger, even when there is no real threat. According to the National Institute of Mental Health, other symptoms of Post-Traumatic Stress Disorder include avoiding places or events that remind you of the traumatic experience, feelings of paralysis or guilt, loss of interest in once-enjoyable activities, tension, fear for nothing, trouble sleeping, and outbursts of anger.

PTSD is very common in military veterans, but it can develop as a result of any type of traumatic event, such as a robbery, kidnapping, car accident, plane crash, physical violence or natural disaster.

Currently, PTSD has been treated with psychotherapies, including exposure therapy, which consists of exposing patients to the trauma originally experienced, but in a safe way; cognitive restructuring, which helps patients reinterpret traumatic memories; and stress inoculation training, which teaches patients how to reduce anxiety. Antidepressant medications are prescribed to help curb feelings of sadness, anger, worry, and inertia. These medications often have side effects, such as headaches, nausea, insomnia or drowsiness, agitation and sexual problems.

Effects of cannabis on post-traumatic stress disorder

Cannabis can help patients with PTSD control their symptoms 19. Two of the main cannabinoids found in marijuana, tetrahydrocannabinol (THC) and cannabidiol (CBD), influence the body’s endocannabinoid system, which plays a fundamental role in maintaining emotional homeostasis and regulating memory consolidation, recovery and extension. The cannabinoids found in cannabis activate the CB1 and CB2 receptors of the endocannabinoid system, which modulates the release of neurotransmitters and produces a series of effects on the central nervous system, including an increase in pleasure and alteration of memory processes 2. Cannabinoids block the continuous memory of the traumatic event, reducing the associated anxiety 1, 9, 18.

These effects help patients with Post-Traumatic Stress Disorder control the three main symptoms of the disorder, which include reliving the experience, avoidance and numbing, and acute stress reaction. Patients diagnosed with PTSD showed a 75% reduction in symptoms of the disorder when using cannabis, compared to when they were not using it, as analyzed by the Clinical PTSD Scale (CAPS) 8.

Military veterans use cannabis for the purpose of overcoming their trauma, especially those who have difficulty controlling emotions and tolerating stressful situations 15. An improvement in the sleeping patterns of those suffering from insomnia or nightmares is one of the main reasons why patients with Post-Traumatic Stress Disorder use cannabis 2, 5, 13. The more severe the symptoms of PTSD, the greater the willingness of veterans to use cannabis to deal with their problems 4, 5, 6. Preclinical evidence demonstrates that CBD has significant potential for treating PTSD when administered acutely as symptoms appear, rather than chronically 3.

However, there is evidence to suggest that the benefits of cannabis for patients with Post-Traumatic Stress Disorder go beyond the temporary. Findings support the idea that cannabis has the potential to lessen the strength and emotional impact of traumatic memories 13. Additionally, administering cannabinoids shortly after exposure to a very stressful event may help prevent the development of symptoms associated with PTSD 7.

Recent studies on cannabis as a PTSD treatment

• Patients with PTSD observed a 75% reduction in the symptoms of the disorder when using cannabis, compared to when they were not using it, as analyzed by the Clinical PTSD Scale (CAPS). Reports of PTSD symptoms from patients evaluated for the New Mexico Medical Cannabis Program.
  http://www.tandfonline.com/doi/full/10.1080/02791072.2013.873843?needAccess=true

• Evidence from human studies indicates that the CBD found in cannabis has significant potential as a treatment for anxiety disorders. Cannabidiol as a possible treatment of anxiety disorders.
  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4604171/
• A review of published evidence finds that cannabinoids help PTSD patients control their three main symptoms (reliving the experience, avoidance and numbness, acute stress reaction) and help improve sleep for such patients who suffer from insomnia and nightmares. Cannabinoid use and effects in veterans with post-traumatic stress disorder. http://www.ajhp.org/content/72/15/1279.long

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