Sidebar: Cannabis Use Disorder
An estimated 8% to 12% of individuals continue cannabis use despite negative effects.
Cannabis use, both medicinal and recreational, has increased as legalization at the state level has expanded. In the United States, 33 states now allow the medical use of cannabis, while 11 allow both medical and recreational use. The Journal of the American Medical Association (JAMA) Network Open reported on a 2019 survey findingthat 35% of respondents acknowledgecannabis use for medical reasons, 45% fornonmedical reasons, and 20% for medicaland nonmedical purposes.1
Research has shown that cannabis may be helpful to manage pain, depression, anxiety, inflammatory bowel disease, seizure disorders, insomnia, inflammation, posttraumatic stress disorder, and many other conditions.2,3 A retrospective cross-sectional survey of patients with chronic pain, as well as other studies, found that states that have legalized cannabis have witnessed a decrease in opioid use and reduced mortality from opioid overdose.4,5
A widely held belief that cannabis use in adolescence negatively affects IQ scores was contradicted by a 2020 twin study, which concluded that there’s little evidence of a causal effect of cannabis on cognition.6 This isn’t to say that there isn’t a potential downside for some cannabis users.
Although cannabis has the potential to provide significant relief for many, if used in excess or at an early age it may cause negative effects. Short-term effects of excessive use may include increased heart rate, distorted perception, loss of coordination, and problems with memory and learning.7 The amount of cannabis used, the potency of the cannabis, and the duration of use will determine the effect on the body. THC is the primary cannabinoid in the cannabis plant responsible for the intoxicating and reinforcing properties of cannabis. The potency of cannabis is determined by the percentage of THC and can range from as low as 1% to 30%.
Much of what’s known about cannabis is based on research pertaining to THC, yet the cannabis plant also contains additional cannabinoids, including CBD; terpenes; and flavonoids.2 CBD has numerous health benefits and has been shown to temper the intoxicating effects of THC.
Those who use cannabis frequently over the long term may experience complications that can affect the neuropsychiatric, physical, and social aspects of health. Negative effects may include dependence, altered brain development, and cognitive impairment. Altered brain circuitry has been seen with prolonged and heavy cannabis use. More research is required to more fully understand the pathophysiological mechanisms.2
Cannabis Use Disorder
Furthermore, some long-term, heavy cannabis users (estimated at 8% to 12%) may develop cannabis use disorder (CUD),8 defined as the continued use of cannabis despite clinically significant distress or impairment that affects behavior and physical and psychosocial aspects of their lives.2
In 2013, the Diagnostic and Statistical Manual of Mental Disorders outlined new criteria or diagnosing CUD, which is “defined by nine pathological patterns classified under impaired control, social impairment, risky behavior, or physiological adaptation.” Manifestations of CUD include cannabis intoxication, cannabis withdrawal, cannabis intoxication delirium, and cannabis-induced psychotic, anxiety, and sleep disorders. Previous terms for these diagnoses were cannabis abuse and cannabis dependence.2 CUD now includes both and is meant to clarify that people can be negatively affected by their cannabis use without necessarily being addicted.
CUD is indicated by the existence of at least two of the following symptoms within a 12-month period9:
• taking more cannabis than was intended;
• difficulty controlling or cutting down on cannabis use;
• spending a lot of time obtaining and using cannabis;
• craving cannabis;
• problems at work, school, and home as a result of cannabis use;
• continuing to use cannabis despite social or relationship problems;
• giving up or reducing other activities in favor of cannabis;
• taking cannabis in high-risk situations;
• continuing to use cannabis despite physical or psychological problems;
• tolerance to cannabis; and
• withdrawal when discontinuing cannabis.
The severity of the disorder is categorized by the number of symptoms a person demonstrates, as follows9:
• mild: two to three symptoms;
• moderate: four to five symptoms; and
• severe: six or more symptoms.
The above criteria for CUD must be carefully considered before making a diagnosis for those individuals using cannabis for medical reasons or under medical supervision. When considering a diagnosis of CUD, clinicians should also examine additional substance use, mental health, family history, medical history, medications, and environmental stressors.2
According to the Substance Abuse and Mental Health Services Administration (SAMHSA), there are 4.1 million people in the United States with CUD. To put this number into context, SAMHSA reports that 14.4 million suffer from alcohol use disorder.10
Treatment of CUD
Treatment may include providing support during detoxification, access to psychiatric services, and counseling to help patients understand their behaviors and develop more healthful coping skills.2
A systematic review of various psychosocial interventions for problematic cannabis use was undertaken in 2016. The review included 23 randomized controlled trials with participants who frequently used cannabis. The intervention types consisted of cognitive behavioral therapy (CBT), a motivational intervention—motivational enhancement therapy (MET)—a combination of MET and CBT, contingency management, social support, mindfulness-based meditation, and drug education and counseling. The study included 4,045 participants with an average age of 28.2. The review included 15 studies from the United States, two from Germany, two from Australia, and one each from Brazil, Canada, Switzerland, and Ireland. The main findings from this review indicated that the intervention type and duration of sessions influenced the outcomes. The most effective outcome was the combination of MET + CBT with sessions numbering more than four and treatment lasting longer than one month.11
Heavy or chronic users of cannabis are more likely to report a decreased sense of life satisfaction and achievement in comparison with the general population.12 As stated previously, MET and CBT have been most effective in reducing the frequency and quantity of cannabis use. Improved outcomes have been observed with longer durations of psychotherapy. There are, however, challenges to treatment that include limited access to evidence-based psychotherapy, low adherence to therapy, and lack of insurance coverage for sessions.
Although research is ongoing, there’s no FDA-approved medication to treat CUD.2 A promising randomized clinical trial found that administration of a nabixmols (Sativex) buccal spray containing a 1:1 ratio of THC and CBD during an inpatient admission for CUD resulted in a significant reduction in craving, irritability, and depression, with concomitant positive improvements in sleep, appetite, restlessness, and anxiety.13 A 2015 review of preclinical and clinical data looked at the use of CBD alone on addictive behaviors. CBD has an effect on several neurotransmission systems involved in addiction and has therapeutic benefits that could indirectly be helpful in treatment, including decreasing anxiety and cravings. Studies have found a decrease in withdrawal symptoms with the use of CBD. The authors conclude that further studies are needed to evaluate the potential of CBD as a treatment for addictive disorders.14
Complicating efforts to research treatment for CUD (and cannabis in general) is the fact that in 1970 cannabis was classified by the Controlled Substance Act as a Schedule I substance. Other Schedule I substances include heroin and LSD (lysergic acid diethylamide). This classification states that cannabis has no currently accepted medical use and a high potential for abuse.15 Many medical experts have long argued that this scheduling is inaccurate. It leads to limited access and restrictions on funding for much-needed scientific research.
While CUD is a potential health issue for a small subset of cannabis users, many people use cannabis with no negative effects and achieve statistically significant benefits, such as reduction in pain, anxiety, inflammation, muscle spasms, and insomnia. Descheduling cannabis will allow further investigation into the positive as well as potentially negative effects of cannabis use.
— Janice Newell Bissex, MS, RDN, FAND, is a certified holistic cannabis practitioner at JannabisWellness.com.
1. Devitt M. Survey examines marijuana use among U.S. adults. American Academy of Family Physicians website. https://www.aafp.org/news/health-of-the-public/20191016marijuanasurvey.html. Published October 16, 2019.
2. Patel J, Marwaha R. Cannabis Use Disorder. Treasure Island, FL: StatPearls Publishing; 2019.
3. Kinnucan J. Use of medical cannabis in patients with inflammatory bowel disease. Gastroenterol Hepatol (N Y). 2018;14(10):598-601.
4. Boehnke KF, Litinas E, Clauw DJ. Medical cannabis use is associated with decreased opiate medication use in a retrospective cross-sectional survey of patients with chronic pain. J Pain. 2016;17(6):739-744.
5. Sarlin E. Study links medical marijuana dispensaries to reduced mortality from opioid overdose. National Institute on Drug Abuse website. https://www.drugabuse.gov/news-events/nida-notes/2016/05/study-links-medical-marijuana-dispensaries-to-reduced-mortality-opioid-overdose. Published May 17, 2016.
6. Ross JM, Ellingson JM, Rhee SH, et al. Investigating the causal effect of cannabis use on cognitive function with a quasi-experimental co-twin design. Drug Alcohol Depend. 2020;206:107712.
7. Buddy T. The negative health effects of marijuana. Verywell Mind website. https://www.verywellmind.com/the-health-effects-of-marijuana-67788. Updated August 20, 2019.
8. Brezing CA, Levin FR. The current state of pharmacological treatments for cannabis use disorder and withdrawal. Neuropsychopharmacology. 2018;43(1):173-194.
9. Hasin DS, O’Brien CP, Auriacombe M, et al. DSM-5 criteria for substance use disorders: recommendations and rationale. Am J Psychiatry. 2013;170(8):834-851.
10. McCance-Katz EF; Substance Abuse and Mental Health Services Administration. The National Survey on Drug Use and Health: 2017. https://www.samhsa.gov/data/sites/default/files/nsduh-ppt-09-2018.pdf
11. Gates PJ, Sabioni P, Copeland J, Le Foll B, Gowing L. Psychosocial interventions for cannabis use disorder. Cochrane Database Syst Rev. 2016;(5):CD005336.
12. Volkow ND, Baler RD, Compton WM, Weiss SR. Adverse health effects of marijuana use. N Engl J Med. 2014;370(23):2219-2227.
13. Allsop DJ, Copeland J, Lintzeris N, et al. Nabiximols as an agonist replacement therapy during cannabis withdrawal: a randomized clinical trial. JAMA Psychiatry. 2014;71(3):281-291.
14. Prud’homme M, Cata R, Jutras-Aswad D. Cannabidiol as an intervention for addictive behaviors: a systemic review of the evidence. Subst Abuse. 2015;9:33-38.
15. Drug scheduling. US Drug Enforcement Administration website. https://www.dea.gov/drug-scheduling