When it comes to cannabis, long-standing prohibition has led to the propagation of myths surrounding the plant. And while is legal in 10 states and medical cannabis legal in 33 (in addition to federal legalization in Canada), these mistruths persist in an attempt to dissuade people from using cannabis.
Thousands of years of use, as well as many studies, have shown that cannabis is a safe substance; however, cannabis use in adolescence has been correlated with mental health problems later in life. Researchers are still trying to untangle this relationship but there is a proven a link. Unfortunately, that is often used as a reason to keep cannabis prohibited, despites its multitude of benefits.
Some people who use cannabis may also experience cannabis use disorder. In terms of myth busting, this condition is widely misunderstood.
The Diagnostic and Statistical Manual of Mental Disorders (DSM) is a guidebook to diagnosing behavioral and mental health conditions, developed by the American Psychiatric Association. According to the latest edition of the DSM (V), cannabis use disorder is defined as “a problematic pattern of cannabis use leading to clinically significant impairment or distress.” This pattern of behavior must be accompanied by at least two types of behavior related to psychosocial or physical problems or signs of cannabis withdrawal or tolerance across a 12-month period.
A person with cannabis use disorder is dependent on cannabis.This is not a myth. And, as it is now included in the DSM, physicians may be more likely to monitor people they suspect are dependent on cannabis. While the DSM does list cannabis use disorder, it remains to be seen what ramifications there are from cannabis dependency. However, the prevalence of this disorder has become a bit of a key item for prohibitionists.
A JAMA Psychiatrystudy based on data from a 2012-13 national survey of 118,497 participants reported that 2.3% of participants had cannabis use disorder in states where medical cannabis was prohibited and 3.1% in states where medical cannabis was legal.  Another study published in The American Journal of Psychiatry found that the lifetime prevalence of cannabis use disorder was 6.3%. In this study, researchers interviewed 36,309 participants using the latest DSM guidelines for diagnosis. 
It is important to note that while these numbers may be a bit lower than what you have seen on certain web sites and channels describing the negative effects of cannabis, the prevalence of cannabis use disorder has increased concurrently with greater legalization, and possibly due to the shift from use of cannabis flower to more potent concentrates. It is also important to note that withdrawal from cannabis is not equal in severity to discontinuing use of alcohol or opiates. 
While there is no therapy approved for cannabis use disorder, it can be treated with psychosocial intervention. Cognitive behavioral therapy, which uses a method of cognitive restructuring and pro-social behaviors, can be very effective.  Additionally, motivational enhancement therapy uses an empathic, non-confrontational approach to promote behavioral changes.
People who use cannabis may experience mental health problems, including dependency on cannabis. However, the prevalence and severity of these conditions are often inflated to paint this substance in a completely negative light – refusing to recognize its benefits. Additionally, whether one becomes dependent on cannabis or develops associated mental health conditions is determined by many different factors, including genetics, age, and environment. To make this situation more complex, those who are dependent on cannabis are more likely to also be dependent on another substance – and those who later develop mental health conditions may self-medicate with cannabis earlier in life before being diagnosed, suggesting a chicken or egg paradox. 
Stay vigilant when reading stories about cannabis-associated mental health conditions and cannabis use disorder. Yes, these are conditions that anyone consuming cannabis should be aware of – but, keep in mind that different studies report different results. And even if data are published on trusted sites, informed consumers should always fact check to verify all cited data.
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