Anxiety

Millions of Americans live with anxiety and panic disorders. Though everyone experiences anxiety and stress from time to time, people with anxiety disorders feel an irrational–and sometimes paralyzing–fear of everyday events. The five most common disorders are generalized anxiety disorder, obsessive-compulsive disorder (OCD), panic disorder, post-traumatic stress disorder, and social anxiety disorder. There’s debate on whether cannabis has a positive or negative impact on those suffering from anxiety, but recent scientific research suggests that it may change the brain’s response from what it would consider “threatening” situations and thus contribute to alleviating these disorders.

THC and the brain’s ability to analyze rational and irrational fear

In a paper published in the Journal of Neuroscience (March 2008), K. Luan Phan, M.D., assistant professor of psychiatry at the University of Michigan, and his former University of Chicago colleagues concluded interesting results from a study using THC, the main ingredient found in cannabis. The study looked at how THC effects response to threat in a brain region called the amygdala - the area that processes signs of danger or warning and decides how to respond. Other researchers have shown this to be a region that’s rich in a receptor called CB1, part of the brain’s “cannabinoid” system. The researchers found that when the volunteers received THC, their brain’s response to “threatening” faces was less than it was when they received a placebo. This suggests that cannabis could be helpful in processing what is rational and irrational fear in the brain of someone suffering from anxiety.

Cannabis use in treating Post-Traumatic Stress Disorder

PTSD, as defined by the National Institute of Mental Health (NIMH), is an anxiety disorder that can develop after exposure to a terrifying event or ordeal in which grave physical harm occurred or was threatened. Traumatic events that may trigger PTSD include violent personal assaults, natural or human-caused disasters, accidents, or military combat. The U.S. military has stated that some 40,000 soldiers sent to Afghanistan or Iraq from 2002-2007 have been diagnosed with PTSD. And according to the NIMH, over 7.5 million Americans are affected by the illness. People with PTSD may startle easily, become emotionally numb (especially in relation to people with whom they used to be close), lose interest in things they used to enjoy, have trouble feeling affectionate, be irritable, become more aggressive, or even become violent.

Giovanni Marsicano, Ph.D., Group of Molecular Genetics of Behaviour Max-Planck-Institute of Psychiatry
Munich, has studied the effects of cannabinoids - the compounds found in cannabis, particularly on the area of the brain that processes fear. His research, published in the science journal Nature (August 2002), found “that a process involving activation of the CB1 receptors by endocannabinoids is essential in the extinction of conditioned fear.” The article goes on to say:

“The finding that the endocannabinoids contribute to extinction raises the possibility that drugs that target these molecules and their receptors could be useful new treatments for anxiety disorders. Finally, there is much anecdotal evidence of patients using cannabis heavily in the early stages of psychiatric illness. This has often been thought to contribute to acute illness. But it seems possible that it may instead be a form of selfmedication for the sometimes extreme anxiety that these people experience.”