Cannabis Instead of SSRI for OCD?
Researchers are working out which cannabinoids will be able to help patients stop repetitive behaviors associated with OCD.
Cannabis is a fighter. It takes on epilepsy, auto-immune disorders, glaucoma, cancer, constipation, pain and so much more—dealing powerful, defeating blows to each. But could it also take down a different sort of opponent, a merciless disease of the mind?
Obsessive Compulsive Disorder is a life stealer. Although people use the term “OCD” in common parlance to refer to a desire to keep an orderly living space, the disorder is very serious. Unstoppable repetitive behaviors mark those who live with it. Chemical imbalances in the brain cause these behaviours.
Typically, the disorder is treated through serotonin regulators. Drugs like fluoxetine and citalopram, known as selective serotonin reuptake inhibitors (SSRIs), are prescribed to help even out the brain chemicals in OCD sufferers. These drugs work by preventing the brain from soaking up the excess serotonin it releases, allowing patients to maintain a base level of normal feelings without having to resort to their compulsive behaviors for a neurochemical reward.
The problem with this treatment strategy is that it only sort of works. As patients’ brains become accustomed to SSRIs, they build up a tolerance to the drugs and the therapy stops being effective. Then OCD sufferers will be looking for a new drug.
That’s where cannabis comes in. In two recent research articles, scientists have outlined new OCD therapies involving the use of cannabidiol (CBD), and the possible ways it can be beneficial to people who are at the mercy of their debilitating brain chemistry.
The First Study
The first study tested mice who had occurrences of repetitive behavior that mimics the experience of adults with OCD.
The research was based on a simple idea. Humans with OCD have brains that bear signs of glutamatergic abnormalities (in lay man’s terms: OCD messes with certain neurotransmitters, making some parts of the brain unable to communicate). Because cannabinoids hinder the release of glutamates by the central nervous system, the study decided to test whether or not that hindrance would eliminate the symptoms of OCD.
The scientist rounded up mice that displayed strong compulsory behaviors and dosed them in two different ways. First, they gave some mice a specific cannabinoid that positively affects the CB1 receptors in the endocannabinoid system. That is, doctors dosed the mice with a chemical boosting the part of the central nervous system cannabis affects. After treatment, those mice showed significantly less compulsive behavior.
To double check their work, the researchers also applied an opposite test. They dosed other mice with a molecule that negatively affected the CB1 receptors. The subjects in those tests showed no changed whatsoever in compulsive behaviors.
Together, the two trials confirmed that the endocannabinoid system plays a vital role in the regulation of OCD-like behaviors and that cannabis-based treatment can be effective in treating such behavior.
A Second Study
A second study took a slightly different track, focusing on the role that phytocannabinoids can play in treating obsessive compulsive disorder.
The study considered how four phytocannabinoids functioned when administered to patients in different ways. The goal was gaining a better understanding of the best way for cannabis-based drugs to be given to patients in order to gain the best outcomes (lowering of obsessive behaviors). First, doctors aimed for the study to look at the longest amount of time. Second was gaining the fewest number of side effects (like drowsiness or decreased mental functions).
The Good News
The good news is that all the cannabis-based medicine tested easily crossed the blood-brain barrier. This means that benefits were easy to come by no matter how patients received treatment. The bad news is that the researchers discovered how the body delivers the medicine makes a big difference in results. And, those results are not consistent across different species of animals. Results were also different depending on the type of cannabinoid used.
The paper shows that mice and rats react to treatment differently based on the method of drug delivery. Each cannabinoid also affected the animals’ results. Giving rats an oral dose of CBD or CBDV (cannabidivarine), for example, results in higher concentrations of those drugs in their brains relative to mice. But for the cannabinoids CBG (cannabigerol) and Δ9-THCV (tetrahydrocannabivarin), the results reverse. That means there’s no good way to extrapolate which way would be more beneficial to humans.
Together, these studies provide an illuminating, but frustrating picture of cannabis’ effect on OCD. Doctors assure the occurrence of OCD involves the endocannabinoid system. However, the exact way this happens is not yet fully understood. What’s more, the existing data indicates that the human brain may react to cannabis-based treatments differently than animal brains. This complicates the issue for future testing.