By Cole Miller
The simple answer is that it’s ambiguous. No one definitively knows the answer to this issue. Cannabis was deemed a Schedule I drug in 1970, classified by the Controlled Substances Act, as being prone to abuse, non-medical, and unsafe to use without supervision. As of today, it is still federally illegal; however, four states have legalized marijuana for adult recreational use (Oregon set to take effect July 1). In addition, twenty-one other states and the District of Columbia currently have laws legalizing marijuana in some fashion, indicating that an abundant number of U.S citizens believe that the drug has beneficial effects or that it’s innocuous enough to be considered legal. But the question still remains: is cannabis addictive? Sources such as the National Institute on Drug Abuse (NIDA) claim marijuana to be undeniably addictive, supporting their opinion with studies showing that 9% of users have a lifetime dependence risk on marijuana. On the other hand, national epidemiological surveys show that a large proportion of people who have had experience with marijuana do not become physically addicted. Controversy has become pervasive and rampant now that an increasing number of U.S states have permitted marijuana in some form.
But how exactly do we define addiction? Is it physical or psychological dependence? Physical dependence refers to a state of negative physical symptoms of withdrawal after sudden cessation of the substance. Psychological dependence involves a craving for the drug and production of emotional symptoms after withdrawal. By examining both sides of the argument surrounding cannabis addiction, as well as the criteria for Cannabis Use Disorder defined by the DSM-III-R, I believe that marijuana should not be defined as an addictive substance.
Some estimates assume up to 9% of marijuana users become addicted; however, this statistic comes from studies based on potentially biased and false criteria for cannabis dependence, which raises questions about its validity. One such study, published in 1994 by the NIDA in the journal Experimental and Clinical Psychopharmacology, bases cannabis dependence on criteria defined by the Diagnostic and Statistical Manual (3rd edition-Revised) in 1987. The sample consisted of 8,098 subjects between the ages of 15 and 54. The study diagnosed respondents as being dependent on cannabis if they met at least three criteria regarding their cannabis use within a one-month period. These criteria, however, were inherently full of bias that ignored the reality of non-problematic or beneficial cannabis use.
At the time of this study, cannabis was still illegal, even for medicinal purposes. Rather than the dependence on cannabis, it could have been the illegality of it that was causing problems. This observation was not accounted for in the criteria developed by the DSM-III-R. For example, criterion 3 specifies, “a great deal of time was spent in activities necessary to get the substance, taking the substance, or recovering from its effects”. Cannabis is prohibited and therefore unavailable for quick and easy production and consumption, necessitating more time to acquire it. Consumers of weed will therefore fulfill this criterion; however, they are not necessarily addicted to the substance. Criterion 1 of cannabis dependence indicates “it was taken in larger amounts or over a longer period than intended,” but if marijuana were being used for medicinal and therapeutic justifications, a user may meet this requirement even if they were not addicted. Often, many individuals discover the helpful, relaxing, and/or medicinal benefits of marijuana after initially consuming it in moderation under the restrictions of prohibition. Once this therapeutic realization is made, like any other pharmaceutical, more medication will be demanded than was previously proposed, supporting the inflated statistic that 9% of users become addicted.
Furthermore, one may go to greater lengths to procure it, similar to the lengths that any individual may go to in order to purchase any palliative medication, even if the benefit is soothing rather than medicinal. Given the laws against cannabis and the significance of consumption to maintain one’s health, the time and effort involved in acquisition may cut into time that could be used for doing other activities. It is not surprising that cannabis use, by virtue of its illegality alone, could lead to foregoing “important social, occupational, or recreational activities… because of substance use,” as defined in criterion 5. Individuals who were not cannabis-dependent were most likely included as such, thereby yielding an inflated result of 9% (approximately 1 in 11 people) for the prevalence of Cannabis Use Disorder among self-identified marijuana users. This is why this statistic is based on biased and erroneous criteria used to measure cannabis dependence and cannot be considered reasonable.
Any substance, from cheeseburgers to Facebook to sex, can essentially be used in an addictive manner; however, for any drug to be recognized as addictive, there needs to be evidence of a substantial proportion of users who show signs of physical and/or psychological dependence after use. National epidemiological surveys indicate that many users of marijuana do not become addicted. For example, Donald Tashkin, a pulmonologist who has studied marijuana for 30 years, of the University of California at Los Angeles, recently published a study at the American Thoracic Society International Conference and found no connection between marijuana and lung cancer – even with regular and heavy marijuana smokers. This is surprising, but reliable, considering that this is a drug that is typically smoked. There is only scant evidence that cannabis use produces physical dependence and withdrawal in humans. Another study, published on October 6 2014, reviews 20 years of existing research into the health effects of marijuana use. In the published paper, Professor Wayne Hall, Director of the Centre for Youth Substance Abuse Research at the University of Queensland, concludes the same statistic that was disproved above: 9% of cannabis users become life-dependent on the drug. However, Hall focuses almost exclusively on the effects of long-term or heavy marijuana use, rather than occasional or moderate use. This important distinction is critical to answering the question of marijuana addiction. As mentioned earlier, this statistic is inflated and skewed due to erroneous criteria as well as an emphasis on heavy cannabis users. There is simply not enough statistically significant evidence to suggest that users of marijuana become physically and/or psychologically dependent.
To answer the original question, is marijuana addictive, the answer is technically still obscure. We don’t know yet. It’s not due to faulty individuals or poor science, but rather due to a limitation in our technology and understanding. However, we can obtain a pretty close estimate. A myriad of people believe that it is addictive, but only 9% of users become dependent. This statistic, based on criteria of the DSM-III-R published in 1987, is most likely inflated and does not hold; therefore we can dismiss this definition of Cannabis Use Disorder. When we define addiction, we ask ourselves if the substance is physically or psychologically dependent. After examining published studies that address the dynamics of cannabis addiction and withdrawal, we can conclude that the use of marijuana does not fall under the categories of physical and/or psychological addiction. Under these criteria, I believe that marijuana consumption cannot be classified as addictive.
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