"Medical" marijuana

Medical Marijuana in Psychiatry

Cannabis has been used for medicinal purposes throughout the world for at least 5000 years. It was used extensively in Western medicine during the late nineteenth century, but fell into decline after potent synthetic medications were introduced in the early twentieth century. Marijuana was also vilified in the popular media, such as in the movie Reefer Madness, an anti-marijuana propaganda film released in the late 1930s.

In recent decades, many proponents of medical cannabis have reemerged, particularly the powerful Marijuana Policy Project, which has been responsible for most of the major state-level marijuana policy reforms. They and others advocate the use of the plant in a smoked or otherwise inhaled form and the cultivation of strains with high concentrations of delta-9 tetrahydrocannabinol (THC) that are claimed to be effective for various ailments.  Even an esteemed judicial representative of the DEA has adopted an ardent stance in favor of medical marijuana…"Marijuana in its natural form is one of the safest therapeutically active substances known to man. By any measure of rational analysis, marijuana can be safely used within a supervised routine of medical care. It would be unreasonable, arbitrary and capricious for the DEA to continue to stand between those sufferers and the benefits of this substance in light of the evidence in this record."- DEA Chief Administrative Law Judge Francis L. Young, Ruling in the matter of Marijuana Rescheduling Petition, September 6, 1988. 

Back to THC…It is the principal psychoactive chemical in cannabis and responsible for the pleasurable effects of relaxation, euphoria and laughter, as well as the negative effects of distorted perception of time and distance, loss of coordination, paranoia and cognitive impairment. Unfortunately, federal regulations, such as the classification of THC as a schedule I controlled substance, as well as the rapid and largely unscientific promotion of medical marijuana nationwide, or what some have called “medicine by popular vote”, have resulted in a scarcity of good scientific evidence on the reputed medicinal benefits of smoked marijuana.

Around the country, medical marijuana cards are routinely given to people suffering from anxiety, depression, insomnia, ADHD, autism and other mental health syndromes. The internet is replete with a growing number of gushing testimonials of successful symptom alleviation through cannabis, including people diagnosed with mood and psychotic disorders such as bipolar and schizophrenia. 

Despite these anecdotal reports as well as misleading advertisements spread by legalization supporters, the reality remains that most of these claims are misguided and unsubstantiated. Sadly, they risk endangering the lives of the very patients they profess to help. Furthermore, no cannabinoid drug has been approved for any psychiatric indication, as the effects of THC are simply too unpredictable to assure any consistent therapeutic response. 


Quite the contrary, according to the National Institute of Drug Abuse, several studies have linked marijuana use in its unprocessed plant form to an increased risk for psychiatric disorders, including schizophrenia, depression, dissociative states, IQ and memory impairment, and substance use disorders, "but whether and to what extent it actually causes these conditions is not always easy to determine...The amount of drug used, the age at first use, and genetic vulnerability have all been shown to influence this relationship." The strongest evidence to date concerns links between marijuana use and other substance use disorders and between marijuana use and psychiatric disorders in those with a preexisting genetic or other vulnerability.  

Interestingly, the antipsychotic effects of cannabidiol (CBD), one of 85 cannabinoids in the Cannabis sativa plant but lacking the psychoactive effects of THC, have been demonstrated in animals and in humans, and supported by functional MRI studies. Additionally, CBD may have potential therapeutic value in PTSD, due to its ability to block “reconsolidation”, in which memories of painful life events are enhanced by exposure to conditioned stimuli. CBD has also been shown to have anti-emetic and anti-inflammatory effects, as well as possible neuroprotective properties. 

In closing, claims for the medicinal usage of marijuana in treating psychiatric disorders are myriad despite the relatively weak medical evidence. However, the potential consequences, especially in young adults, are numerous. Notwithstanding, the human cannabinoid system is widespread and involved in the regulation of several physiological mechanisms, some of which may be beneficial. Targeted pharmacotherapies based on specific cannabinoids found in marijuana, such as CBD, may hold promise in the treatment of psychiatric and other illnesses, if politics can be put aside in the interest of advancing solid medical research. Wishful thinking, I suppose.  

Scott Zentner