US experts reviewed research into the possible causes of OCD and the potential for using cannabinoids in treating the condition.
Obsessive-compulsive disorder (OCD) is a mental illness in which the sufferer has unwanted intrusive obsessive thoughts that make them extremely anxious and distressed. These thoughts are combined with repetitive compulsive behaviors that they act out in an attempt to relieve obsessive thoughts. For example, a common obsession in OCD is anxiety about contamination or dirt. This is often combined with compulsive hand-washing and cleaning behaviors.
Current treatments for OCD are not effective in some patients
OCD goes far beyond the normal anxious thoughts and behaviors that most people experience to some degree. It is a disabling mental illness that interferes with normal daily life. OCD is estimated to affect around 2-3% of people worldwide over the course of their lifetime. Certain antidepressant and antipsychotic medications can relieve OCD symptoms. However, these drugs are not effective in some patients and may have unpleasant side effects, so new therapies are needed.
The underlying causes of OCD are not fully understood but may be linked to disruptions in pathways and signaling systems in the central nervous system (CNS). Experts in New York, USA, reviewed research into the neurological causes of OCD and the potential use of cannabinoids in treating the condition. They recently published their review in Cannabis and Cannabinoid Research.
Disruption of the Endocannabinoid System (ECS) may underlie OCD
Growing evidence from animal experiments and neuroimaging studies in humans suggests that disruption of Endocannabinoid System (ECS) in the brain could have a role in anxiety, fear, and repetitive behaviors. The ECS is widely distributed in the CNS and is made up of multiple nerve pathways, endogenous (produced in the body) cannabinoid neurotransmitters (eCBs), eCB receptors, and enzymes that make and breakdown eCBs. Broadly speaking, the ECS prevents excessive nerve activation, appearing to “act as a brake mechanism” and support the brain’s ability to “relax, sleep, forget, and protect”.
Cannabinoids or agents targeting the ECS could provide new OCD treatments
Exogenous (present in the environment) cannabinoids include “phytocannabinoid” compounds found in the cannabis plant and synthetic cannabinoids made in the laboratory. Animal experiments have found that exogenous cannabinoids can relieve OCD-like symptoms. Furthermore, some OCD patients who smoke cannabis have anecdotally reported relief from their OCD symptoms. Preliminary clinical studies with cannabinoids in OCD patients have supported this observation.
These findings suggest that developing new medications that target the ECS could be useful in treating OCD. The reviewers point out that careful consideration should be given to the selection of test cannabinoid agents, since eCB receptors are found widely in the CNS, so there is potential for unwanted side effects. Agents targeting other ECS components, such as eCB enzymes, could provide other test treatment options. “Only further exploration of this topic will determine whether cannabinoids pass the most important test: Helping more patients with OCD to achieve wellness,” concluded Dr. Reilly Kayser, the lead author of the review.
Written by Julie McShane, MA MB BS
- Kayser RR, Snorrason I, Haney M, et al. The endocannabinoid system: a new treatment target for obsessive compulsive disorder? Cannabis and Cannabinoid Research 2019;4(2):1-11).
- Mary Ann Liebert Inc.(Publishers), Press release 31 May 2019. “Can cannabinoids help treat ovsessive compulsive disorder?” https://www.eurekalert.org/pub_releases/2019-05/mali-cch053119.php