Could Cannabis be the Solution to PTSD?

While it may be regarded by some as a ‘soldiers’ disease studies have found that post-traumatic stress disorder (PTSD) affects about 9%  of the U.S population and almost 8% of the European population. Furthermore, almost a third of patients who receive a diagnosis of PTSD will not see recovery even after many years of treatment. While monoamine oxidase inhibitors (MAO-I) have previously used with some success to reduce some of the symptoms of PTSD, new research has suggested a different type of pharmacological approach might achieve substantially greater success. This new approach centres on the endocannabinoid system which can be triggered by agonistic ligands such as the Colorado favourite, cannabis.

This research has stemmed from the data that shows that cannabis abuse is higher amongst Vietnam veterans who have been diagnosed with PTSD and the notion that the abuse could be stemming from some attempt to self-medicate.

Cannabis is known to work by activating the CB1 and CB2 receptors in the brain that are usually regulated by the endocannabinoid anandamide (ANA). Studies have shown that these receptors are linked to the consolidation, retrieval, and extinction of emotionally charged memories. Furthermore, these studies have shown that patients with PTSD tend to have an upregulation of CB1 receptors in the brain that coincides with low levels of ANA. The studies then sought to see what occurred when the administration of an ANA agonist did to the formation of PTSD in a subject. The studies found that, in rodents, ANA agonists did disrupt the retrieval while facilitating the extinction of emotionally arousing experiences. However, some did discover that too early of an administration caused the agonist to actually exacerbate the original consolidation of the experience.

There is also some research going into whether or not the activation of CB1 and CB2 receptors have some downstream effect on glucocorticoid production through interaction with the HPA axis.

While cannabinoids seem to be a promising treatment for PTSD much more research is needed in order to discover their true ability to heal as well as their potential to be abused. I think that the administration of a agonist that helps regulate ANA levels without producing the psychogenic effects of cannabis would most likely be the best candidate for a viable treatment in those suffering from PTSD. However, since the popularization of cannabis will it be the more sought after/cheaper treatment or will sufferers look to a less abused option? Also why is there a possibility of ANA agonists making PTSD more severe when taken too soon after a traumatic experience, is it a difference between the two receptors? If there is a difference between the receptors could an antagonist at one be used to prevent the consolidation of the memory immediately after the traumatic event and the agonist of the other be used to prevent its retrieval?

References

Hauer, D., Kaufmann, I., Strewe, C., Briegel, I., Campolongo, P., & Schelling, G. (2014). The role of glucocorticoids, catecholamines and endocannabinoids in the development of traumatic memories and posttraumatic stress symptoms in survivors of critical illness. Neurobiology Of Learning & Memory, 11268-74. doi:10.1016/j.nlm.2013.10.003

Neumeister, A., Seidel, J., Ragen, B. J., & Pietrzak, R. H. (2015). Translational evidence for a role of endocannabinoids in the etiology and treatment of posttraumatic stress disorder. Psychoneuroendocrinology, 51577-584. doi:10.1016/j.psyneuen.2014.10.012

Trezza, V., & Campolongo, P. (2013). The endocannabinoid system as a possible target to treat both the cognitive and emotional features of post-traumatic stress disorder (PTSD). Frontiers In Behavioral Neuroscience, 7doi:10.3389/fnbeh.2013.00100