Is Cannabis Addictive?
There is a difference between addiction and physical dependence, and tolerance for that matter. Clinical trials looking at the harms of Cannabis, largely funded by the National Institute on Drug Abuse (NIDA), often use dependence as the outcome of interest. Dependence does not constitute addiction, but often accompanies it.1 Dependence represents the collection of physiological responses within the body to the withdrawal of a substance after prolonged use or exposure. Addiction is “compulsive drug use despite harmful consequences”.2 Physical dependence, or withdrawal, may also be involved, depending on the drug.
Can physical dependence result from Cannabis use? Yes, but heavy and prolonged use are required and cannabis withdrawal is typically mild, short in duration and self-limited.
Alan Budney PhD, a clinical researcher and Professor at the Geisel School of Medicine at Dartmouth has conducted pioneering research in an effort to characterize Cannabis withdrawal.3,4 According to his, and other research,Cannabis withdrawal is typically mild, short in duration and self-limited, meaning it resolves spontaneously. Common signs and symptoms include: irritability, anger, anxiety, depression, restlessness, sleep difficulty, decreased appetite or weight loss, abdominal pain, nausea or vomiting, muscle aches or twitching, shakiness or tremors, sweating, fever or chills, and/or headache.5,6
This withdrawal pattern is less severe than many other licit and illicit drugs, including opioids, benzodiazepines, alcohol and nicotine. Research shows that withdrawal symptoms tend to occur in 6 out of 10 heavy users, and last up to 2 weeks.6,7
Research is less clear on how long an individual must use Cannabis - and at what dose and frequency - in order to experience withdrawal symptoms after cessation.
Is Cannabis Addictive? Yes, but the risk is low and highly dependent on the dose and frequency of use.
Estimating the number of people addicted to marijuana is difficult for a variety of reasons. Most importantly, many epidemiological studies use dependence as a surrogate for addiction, despite the fact that addiction does not require physical dependency. Two studies conducted in 1994 and 2011 suggest that approximately 9% of people who use marijuana will develop dependence.8,9 The percentage is higher among those who start using in their teens, approximately 17%.10
* Anthony JC, Warner LA, Kessler RC. Comparative epidemiology of dependence on tobacco, alcohol, controlled substances, and inhalants: Basic findings from the National Comorbidity Survey. Exp Clin Psychopharmacol. 1994;2(3):244-268. doi:10.1037/1064-1297.2.3.244.
Clinical Diagnosis
In clinical practice, a patient using Cannabis in large doses and on a regular basis may be diagnosed with a Cannabis Use Disorder, per Diagnostic and Statistical Manual of Mental Disorders (DSM), published by the American Psychiatric Association (APA).11 According to the DSM-V, an individual may be diagnosed with a Cannabis Use Disorder if they meet the following criteria:
A problematic pattern of cannabis use leading to clinically significant impairment or distress, as manifested by at least two of the following, occurring within a 12-month period:
Cannabis is often taken in larger amounts or over a longer period than was intended.
There is a persistent desire or unsuccessful efforts to cut down or control cannabis use.
A great deal of time is spent in activities necessary to obtain cannabis, use cannabis, or recover from its effects.
Craving, or a strong desire or urge to use cannabis.
Recurrent cannabis use resulting in a failure to fulfill major role obligations at work, school, or home.
Continued cannabis use despite having persistent or recurrent social or interpersonal problems caused or exacerbated by the effects of cannabis.
Important social, occupational, or recreational activities are given up or reduced because of cannabis use.
Recurrent cannabis use in situations in which it is physically hazardous.
Cannabis use is continued despite knowledge of having a persistent or recurrent physical or psychological problem that is likely to have been caused or exacerbated by cannabis.
Tolerance, as defined by either of the following:
A need for markedly increased amounts of cannabis to achieve intoxication or desired effect.
Markedly diminished effect with continued use of the same amount of cannabis.
Withdrawal, as manifested by either of the following:
The characteristic withdrawal syndrome for cannabis.
Cannabis (or a closely related substance) is taken to relieve or avoid withdrawal symptoms.
The severity of a Cannabis Use Disorder can be classified into Mild, Moderate and Severity categories based on the number of criteria met:
Mild: Two to three symptoms
Moderate: Four to five symptoms
Severe: Six or more symptoms
The bottom line
Regardless of whether an individual is formally diagnosed with a Cannabis Use Disorder, patients should be aware that physical dependence and addiction are potential risks of frequent and prolonged use, especially at high doses. Importantly, the severity and duration of any functional impairment resulting from Cannabis dependence is milder than many commonly used licit and illicit drugs.
In health,
Dosing and administration of cannabinoids is complicated, despite the favorable safety profile of Cannabis. The process should be highly individualized and is best supervised by a trained healthcare professional. For more information, please consider booking a consultation (telephone or in-person) with Dr. Jamie Corroon, ND, MPH.
References:
1. Is there a difference between physical dependence and addiction? | National Institute on Drug Abuse (NIDA). https://www.drugabuse.gov/publications/principles-drug-addiction-treatment-research-based-guide-third-edition/frequently-asked-questions/there-difference-between-physical-dependence. Accessed March 30, 2017.
2. Is marijuana addictive? | National Institute on Drug Abuse (NIDA). https://www.drugabuse.gov/publications/research-reports/marijuana/marijuana-addictive. Accessed March 30, 2017.
3. Alan J Budney, PHD. https://geiselmed.dartmouth.edu/faculty/facultydb/view.php?uid=4770. Accessed March 30, 2017.
4. Allsop DJ, Copeland J, Norberg MM, et al. Quantifying the clinical significance of cannabis withdrawal. Verdejo García A, ed. PLoS One. 2012;7(9):e44864. doi:10.1371/journal.pone.0044864.
5. Gorelick DA, Levin KH, Copersino ML, et al. Diagnostic criteria for cannabis withdrawal syndrome. Drug Alcohol Depend. 2012;123(1-3):141-147. doi:10.1016/j.drugalcdep.2011.11.007.
6. Budney AJ, Hughes JR. The cannabis withdrawal syndrome. Curr Opin Psychiatry. 2006;19(3):233-238. doi:10.1097/01.yco.0000218592.00689.e5.
7. Cuttler C, Mischley LK, Sexton M. Sex Differences in Cannabis Use and Effects: A Cross-Sectional Survey of Cannabis Users. doi:10.1089/can.2016.0010.
8. Lopez-Quintero C, Cobos JP de los, Hasin DS, et al. Probability and predictors of transition from first use to dependence on nicotine, alcohol, cannabis, and cocaine: Results of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). Drug Alcohol Depend. 2011;115(1-2):120-130. doi:10.1016/j.drugalcdep.2010.11.004.
9. Anthony JC, Warner LA, Kessler RC. Comparative epidemiology of dependence on tobacco, alcohol, controlled substances, and inhalants: Basic findings from the National Comorbidity Survey. Exp Clin Psychopharmacol. 1994;2(3):244-268. doi:10.1037/1064-1297.2.3.244.
10. Hall W, Pacula RL. Cannabis Use and Dependence : Public Health and Public Policy. Vol One. Cambridge University Press; 2003. http://espace.library.uq.edu.au/view/UQ:40493. Accessed March 30, 2017.
11. Diagnostic and Statistical Manual of Mental Disorders (DSM–5). http://www.psychiatry.org/psychiatrists/practice/dsm. Accessed March 30, 2017.
