Anecdotal feedback from those using cannabis to treat Post Traumatic Stress Syndrome (PTSD) has been very positive and promising, but physicians continue to be wary without scientific evidence. However, two new studies provide evidence on how cannabis and cannabinoids are able to treat PTSD so effectively.
Researchers at Wayne State University in Detroit, MI, looked at how cannabis use impacts the amygdala response of those dealing with trauma-related anxiety like PTSD. Previous research has shown that cannabis has the potential to reduce anxiety. But no previous studies had investigated this response in adults dealing with trauma such as PTSD.
The Wayne State University researchers studied the amygdala responses in three groups of participants — 1) healthy controls who had not been exposed to trauma, 2) trauma exposed adults without PTSD, and 3) trauma exposed adults with PTSD. Using a randomized, double-blind procedure, the 71 participants were either given a low dose of THC or a placebo. They were then exposed to threatening stimuli and their amygdala responses recorded. The study revealed that those exposed to THC had lowered threat-related amygdala reactivity.
Results showing measurable signs of reduced fear and anxiety were found in all three groups, which suggests that even those with PTSD were able to experience less fear with THC in their system.
The authors conclude that the research suggests that, “THC modulates threat-related processing in trauma-exposed individuals with PTSD.” The authors add that the drug “may prove advantageous as a pharmacological approach to treating stress- and trauma-related psychopathology.”
A second study, from researchers at Brazil’s Federal University of Paraná, focused on how cannabis could help those with PTSD by extinction of the memories of their trauma. Yale associate professor of psychiatry, R. Andrew Sewell, first suggested that cannabis may be able to help PTSD patients “overwrite” traumatic memories with new memories in a process called ‘extinction learning’.
For most of those who experience traumatic incidents, fear subsides after six months or so due to this process. New memories become associated with the action and override the old. But for those with PTSD, extinction learning doesn’t happen. The trauma attached to the old memories continues to cause problems.
Sewell believed that cannabis could help. Cannabis stimulates CB1 – a receptor in the endocannabinoid system that has improved extinction learning in animal studies. Interestingly, those with PTSD show impaired functioning of the endocannabinoid system, which may be why they are unable to go through the normal extinction learning process.
This recent study from Brazil’s Federal University of Paraná takes a deeper look into the questions Dr. Sewell presented. These researchers conducted a thorough review of the cannabis literature from 1974-2020 looking for evidence from controlled human trials to support or refute the theory that cannabis helps with extinction of traumatic memories.
They found that cannabis could help. Low doses of the cannabinoid THC or THC combined with CBD, another cannabinoid, were both able to enhance the extinction rate for challenging memories and reduce overall anxiety responses. Their study shows that THC drives the rate of extinction learning, while CBD can help alleviate potential side effects from higher doses of THC.
The authors concluded that the current evidence from both healthy subjects and PTSD patients suggests that these forms of cannabis “suppress anxiety and aversive memory expression without producing significant adverse effects.”
While these studies provide additional data on how Cannabis can help to alleviate and possibly even cure PTSD, on-going research will reveal even more about the extent of uses for this curative plant.