Is Cannabis Addictive?

How addictive?

There is absolutely no question that cannabis can be addictive, but it is fiercely debated how addictive it truly is. According to the field of addiction psychiatry, a group of specialists who have generally been anti-cannabis for half a century and who have promoted many of the U.S. Government’s mistruths about cannabis in the past, “cannabis use disorder”, (CUD), a term used synonymously with cannabis addiction, is diagnosed objectively when patients fulfill a certain number of criteria over time that have been carefully validated (see below) -- just as is done for addiction to opioids or alcohol.

Some of these symptoms that contribute to a diagnosis of cannabis addiction include tolerance, withdrawal, cravings, inability to control use, use in hazardous circumstances, and continued use despite negative consequences. This is not very different from how we diagnose other use disorders except that there are no provisions for medical cannabis patients who are getting needlessly saddled with a diagnosis of “cannabis addiction” merely because they have ‘tolerance’ and ‘withdrawal’. We all have tolerance and withdrawal to many of our prescribed medications – no one says you are addicted to your SSRI, or your coffee for that matter. When diagnosing opioid use disorder, these two qualifiers – tolerance and withdrawal – don’t count if the opioids are medically prescribed, because all patients would have tolerance and withdrawal but not all of them are addicted. So why wouldn’t the same be true for diagnosing cannabis addiction, for the millions of medical cannabis patient? In short, this is how the addiction specialists, operating under the hangover of the War on Drugs, have been (in my opinion) vastly overestimating the number of people with cannabis addiction, to the detriment of all involved.

According to the addiction psychiatrists, the consequences of having CUD can be quite severe (this is true), especially in teens and young adults who are particularly susceptible (this is true). CUD is associated with lower happiness, an unsatisfying social life, lack of career success, lower socioeconomic status, car crashes, emergency room visits, cognitive decline, problems with other drugs, other psychiatric diagnoses, suicide, and low motivation (though, these are misleading; the concept of “associated” is a big problem – it is not causation; other issues, such as poverty, can be an alternative explanation). According to many addiction specialists, use of cannabis should generally be discouraged, except, perhaps if the use is “medical” which they have been skeptical about (less and less so). They believe all drug use is bad (except, perhaps, the social use of alcohol, which caused 172,000 deaths last year).

Many addiction psychiatrists believe that CUD is extremely common and cite studies that show that CUD afflicts up to a quarter to a third of adult cannabis users (which is untrue). According to the American Society of Addiction Medicine (ASAM), “between 9.3% and 30.6% of American adults who use cannabis have CUD.” The fact that this range is gigantic—more than a factor of three begs the question of whether the criteria are somewhat, or possibly vastly, overinclusive and whether they are sensibly applicable to medical cannabis patients (they aren’t). Many are concerned that the legalization of cannabis will result in more cannabis users (this is true) and, consequently, more people that succumb to cannabis addiction (likely true – a proportion of people using any intoxicant get addicted). Regular cannabis users can get withdrawal symptoms which can make it harder to quit.

Many people in the cannabis community don’t believe that cannabis is addictive at all—they think it is just another bogus U.S. government propaganda point. Of note, it was a propaganda point, but that doesn’t mean it isn’t true. A common story is, “I used it for twenty years and then I was able to stop on a dime without any problems. How can it be addictive?” Others think it can be mildly or infrequently addicting, with an occasional person who goes off the rails. Cannabis proponents point out that the majority of studies of its addictiveness have been funded and conducted under the auspices of the War on Drugs, where there was, and still is, massive institutional pressure to demonstrate harm over benefits. (This is true).

How do we disentangle all of this?

What is the definition of cannabis addiction?

There are eleven criteria for CUD. A patient needs to have two out of the eleven of these criteria for at least a year to qualify as “addicted” to cannabis, accompanied by “significant impairment of functioning and distress.” Keep in mind that if you meet two or three criteria you have mild CUD, if you meet four or five you have moderate CUD, and six or more means severe CUD.

The 11 criteria are:

1. Use of cannabis for at least a one-year period, with the presence of at least two of the following symptoms, accompanied by significant impairment of functioning and distress.

2. Difficulty containing use of cannabis—the drug is used in larger amounts and over a longer period than intended.

3. Repeated failed efforts to discontinue or reduce the amount of cannabis that is used.

4. An inordinate amount of time is occupied acquiring, using, or recovering from the effects of cannabis.

5. Cravings or desires to use cannabis. This can include intrusive thoughts and images, and dreams about cannabis, or olfactory perceptions of the smell of cannabis, due to preoccupation with cannabis.

6. Continued use of cannabis despite adverse consequences from its use, such as criminal charges, ultimatums of abandonment from spouse/partner/friends, and poor productivity.

7. Other important activities in life, such as work, school, hygiene, and responsibility to family and friends, are superseded by the desire to use cannabis.

8. Cannabis is used in contexts that are potentially dangerous, such as operating a motor vehicle.

9. Use of cannabis continues despite awareness of physical or psychological problems attributed to use—e.g., anergia, amotivation, chronic cough.

10. Tolerance to cannabis, as defined by progressively larger amounts of cannabis needed to obtain the psychoactive effect experienced when use first commenced, or noticeably reduced effect of use of the same amount of cannabis.

11. Withdrawal, defined as the typical withdrawal syndrome associated with cannabis, or cannabis or a similar substance is used to prevent withdrawal symptoms.

What’s wrong with this?

This is a nuanced discussion which I go over it in granular detail in my recent book, “Seeing Through the Smoke.” The gist of it is:

There are many reasons why our definition of cannabis addiction is not only broken but has been harmful to people.  It is overly inclusive, which I will discuss below. When you give someone a definition of “addiction” (to anything…) when they aren’t addicted, it harms them. They are treated with stigma and judgment by their healthcare providers and are discriminated against by insurance companies. This can result in tangible harms. For example, it has been demonstrated that people who are labeled with any addiction are prescribed fewer pain medications by their doctors and are not treated with as much compassion. Doctors unfortunately share the same stigma against addiction that most other people do.

Dr. Staci Gruber is a brilliant researcher at Harvard Medical School and is the director of the Marijuana Investigations for Neuroscientific Discovery (MIND) program. As she puts it,

As in the case of opioid use disorder, for example, tolerance and withdrawal criteria are not considered for individuals who are using opioids under appropriate medical supervision. With regard to cannabis, similar exclusions from DSM-5 criteria may need to be applied.

I’d get rid of the “may” part. In fact, in a 2013 paper, “DSM-5 Criteria for Substance Use Disorders: Recommendations and Rationale,” author Deborah Hasin, who has authored several of these studies implicating 30 percent of adult cannabis users as addicted, argues,

An important exception to making a diagnosis of DSM-5 substance use disorder with two criteria pertains to the supervised use of psychoactive substances for medical purposes, including stimulants, cocaine, opioids, nitrous oxide, sedative-hypnotic/anxiolytic drugs, and cannabis in some jurisdictions. These substances can produce tolerance and withdrawal as normal physiological adaptations when used appropriately for supervised medical purposes. With a threshold of two or more criteria, these criteria could lead to invalid substance use disorder diagnoses even with no other criteria met. Under these conditions, tolerance and withdrawal in the absence of other criteria do not indicate substance use disorders and should not be diagnosed as such. (emphasis added) If the patient is using benzodiazepines, opioids, or cannabis for legitimate medical purposes, we ought to completely ditch the criteria of tolerance or withdrawal, as these are intrinsic parts of many medicines that we routinely use.

Even the person giving us studies that demonstrate a 30% addiction rate among adult users of cannabis thinks the definitions are broken. (And what does “in some jurisdictions” have to do with anything? Either cannabis is or isn’t a medicine—it’s a pharmacological thing, not something decided by the legislature or voters in Mississippi or Vermont. If a policeman is chasing me and I make it over the border from Idaho into Oregon, are my tolerance and withdrawal suddenly valid and noncontributory to a diagnosis of addiction?)

For all the reasons cited above, Dr. Gruber concludes,

CUD is likely a unique construct among those using cannabis medically, and existing tools developed for use in recreational consumers do not appear to be reliable, valid measures for assessing CUD in medical cannabis patients.

I believe that estimates of CUD have been wildly inflated by roping in millions who use cannabis medically (often with great benefit). I would abandon the concept of CUD altogether and start from scratch. We need to create an untainted measure of cannabis addiction that accommodates the current realities of the drug to better target (and not mistarget) treatment.

How I would fix the definition of cannabis addiction

Given that no one is going to ditch this definition, and that some people clearly do get into trouble with cannabis, how can we adjust the sensitivity of the definition of CUD so it better reflects reality?

I would start by eliminating the categories of withdrawal and tolerance. This makes sense given how many useful and commonplace medications have tolerance and withdrawal as common features of their use, such as opioids, benzodiazepines, and antidepressants. This change would help avoid ensnaring the many patients who are using cannabis for medical reasons, or for reasons of wellness and enhancement, into an unhelpful category of “addicted.”

Next, I would go back to the widely accepted tradition that addiction is a clinically diagnosed disease. We should get rid of this habit of diagnosing millions of people by computer-assisted telephone interviews which, with cannabis, just appears to create this hypothetically addicted body of people who don’t seem to materially exist.

Next, I would increase the number of criteria one needs to qualify for CUD. There is evidence to suggest that a higher number of criteria results in a more accurate diagnosis. The more criteria you require, the more cases you might miss, but the more diagnostic certainty you have for the cases you have diagnosed. Given that we appear to be over-diagnosing cannabis addiction, this seems like a good trade-off, as it would help us to be more certain about the cases we diagnose. It would also help the patients take the diagnosis seriously. If we get rid of tolerance and withdrawal (so there are now nine not eleven criteria) and made it so that you needed four out of nine to qualify (instead of the current two out of eleven), this would be much more accurate. If we did this, a more reasonable number of people given a diagnosis of CUD would actually have a clinically meaningful CUD.

In fact, some recent studies have shown that it is almost entirely “severe CUD,” meaning six or more criteria met (of the eleven), that is associated with psychosocial problems. In my schema (without withdrawal or tolerance), that would equate to needing to meet four out of nine criteria. The main difference is that if we tightened this up, we wouldn’t needlessly be diagnosing, pathologizing, stigmatizing, and, as a consequence, harming so many people who are using cannabis without problems and with benefit.

Further, I would search for a way to incorporate the positives of cannabis use into our diagnostic considerations, to get a more nuanced view of why someone is using cannabis. I understand that this isn’t a common feature of diagnosing an addiction, but it is the only way to make our approach to cannabis—which is a medicine as well as a drug of potential misuse, and which can have positives and negatives at the same time—remotely coherent. There was a recent, excellent article about this, “Harm reduction isn't enough: Introducing the concept of Mindful Consumption and Benefit Maximization (MCBM)’.

My personal opinion is that cannabis is about as addicting as caffeine. People get extremely dependent on caffeine, yet still manage to enjoy fulfilling lives, not unlike the use of cannabis for many people. Caffeine usually isn’t particularly disruptive, unless you develop palpitations, heartburn, anxiety, or insomnia. Heavy, regular users of either cannabis or caffeine are susceptible to symptoms of cravings, tolerance, and withdrawal symptoms. The use of neither should be stigmatized or criminalized.

Finally – there a misconception that “all drug use is bad”  under any circumstances (except, of course, alcohol…) which I disagree with, but that is for another day.