How much is too much?

While medical cannabis helps many people, there are rare cases of people who experience cannabis use disorder from an increased tolerance of THC

According to a 2016 study by the National Institutes of Health, CUD is believed to affect 2.5% of American adults (nearly 6 million people) each year, and 6.3% of adults over the course of a lifetime.

According to a 2016 study by the National Institutes of Health, CUD is believed to affect 2.5% of American adults (nearly 6 million people) each year, and 6.3% of adults over the course of a lifetime.

illustration by maria ratinova

Medical cannabis helps many people suffering from chronic pain, seizures, appetite loss, anxiety and post-traumatic stress disorder. And for others, cannabis is a tool for relaxation that comes with fewer side effects and long-term health impacts than alcohol.

But what about the rare cases in which cannabis can harm its user?

In the past, many advocates shied from acknowledging the risks of cannabis dependence for fear of lending credence to the prohibitionists who use pseudoscience and fear-mongering to support an anti-cannabis agenda.

Even if few advocates are talking about it, cannabis use disorder has been categorized in the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders since 2013. According to a 2016 study by the National Institutes of Health, CUD is believed to affect 2.5% of American adults (nearly 6 million people) each year, and 6.3% of adults over the course of a lifetime.

To be clear, there is no evidence that cannabidiol, or CBD, causes dependency, as it does not elicit a psychoactive response in the brain—i.e. its health benefits come without a “high.” THC is the main cannabinoid associated with altered states; therefore cannabis use disorder primarily concerns the intake of THC.

Many consider THC, and cannabis as a whole, one of the lowest-risk and most health-promoting drugs around (far more, many would argue, than any number of pharmaceuticals).

But as a substance that alters the body’s dopamine system, it poses some risks for dependence and addiction. Dopamine is the neurotransmitter that regulates reward, motivation and self-control, and it’s well-established that any substance or activity that affects dopamine—including alcohol, opioids, caffeine and other stimulants such as food and sex—can induce dependency or addiction.

Definition and diagnostics

Cannabis dependence is a physical condition defined by increased tolerance to THC and the presence of withdrawal symptoms such as irritability, depression, digestive issues, nightmares and heart palpitations when a person stops using. Addiction, on the other hand, is a psychological condition when a person loses control over when and how frequently to use. A person with CUD may have a physical dependence or a psychological addiction to cannabis, or both.

What CUD feels like

A.B., a San Diego resident who has been in recovery from CUD for two years, describes feeling like he had to smoke cannabis multiple times every day to function at a basic level.

“At its worst, it was strange for me to be sober. I couldn’t stand it,” he said. “The lights were too bright, the sounds too loud … all the things you would associate with being on a drug—that was me not smoking.”

He resolved many times to quit, but his willpower would last only a day or two. A.B. (SN&R is withholding his full name to protect his privacy) described a moment when he realized that his sense of reality was deteriorating. He had just driven to a work event in a nearby city. After parking, he smoked a bowl, then threw the weed and the bowl away, telling himself—as he had many times before—that he would never smoke again.

“Then, I stepped out of the parking structure and it occurred to me that I had no idea which building to go to,” A.B. said. “Then I realized I actually had no idea where I was at all. I had to sit down for awhile to figure out if it was in L.A., or San Francisco, or even another country—that’s how addled my brain was.”

These kinds of experiences continued for the next couple of years, but when his cannabis use finally cost him his job and threatened his long-term relationship, he sought help. He attended a residential drug and alcohol treatment program for five weeks, when therapy and peer support helped him through the initial stages of withdrawal.

Abstinence from THC, he said, is the only thing that works for him, but that isn’t easy with adult-use cannabis now legal in California. But just like many others recovering from drug or alcohol dependency, A.B. believes in the power of group support and in replacing habitual use with other habits such as playing guitar or exercising.

A.B. also uses sublingual CBD oil to help offset the side effects of quitting THC. He says that has helped him cope with the anxiety, insomnia and nightmares that resulted when he stopped smoking cannabis.

A.B.’s experience is validated by experts. According to Bill Code, an anesthesiologist and integrative medicine specialist who works with medical marijuana patients in Canada, cannabis addiction is possible for certain people who use it habitually.

“But thankfully,” he told SN&R, compared to opioids, alcohol and many other substances, “it’s a relatively simpler addiction to solve.”

Who’s at risk?

The 2016 NIH study showed that men are twice as likely as women to develop CUD, and younger users are more susceptible than those older than 45. Those who start using cannabis as teenagers are also thought to be more likely to develop dependency and addiction. Genes may play a role in predisposition to CUD, and there could be a link between the disorder and pre-existing mental health conditions or family histories of them.

CUD on the horizon

Brian Couey, director of outpatient services at the Betty Ford Center in San Diego, told SN&R that he has observed a slight increase in the number of patients with CUD since recreational legalization took effect in California.

“Anything that’s given more latitude legally sees a small increase in usage,” he said. And since a certain percentage of the population who uses cannabis will develop problems, more usage leads to more dependency.

Rav Ivker, an osteopath in Boulder, Colorado, who frequently prescribes medical marijuana for chronic pain patients, told SN&R that the increasing availability of heavily concentrated products that contain as much as 95% THC, such as shatter, wax and resins, are partly responsible for the rise of CUD. Because “dabbing” delivers a strong and rapid high, it affects the dopamine system more dramatically and poses a larger risk for addiction.

Education, prevention and treatment

Despite growing awareness, CUD remains under-recognized and undertreated. Certain pharmaceuticals show promise in helping address the disorder, though it’s unclear whether they will come with unintended consequences.

Doctors and addiction specialists say that education and prevention are two of the most important factors. Guiding teens and young adults to avoid heavy cannabis use as well as products with high concentrations of THC is key. When prescribing medical marijuana, Ivker said, “in the strongest possible terms, I tell my young patients, ’You’ve got to avoid using high THC products on a daily basis.’”

Treatment for cannabis use disorder often includes abstinence from THC along with cognitive behavioral therapy—much like the solution A.B. found. Though he believes in the healing power of the plant for those who need it and feels nostalgic for the times when cannabis felt like a good fit for him, he hopes that people will become more aware of the potential risks of heavy use.

“At its best, weed was something that made me more creative, more social—a better version of me,” he said. “But at its worst, I was unable to function or to have any real relationships in my life.”