Is Marijuana Addictive?
It’s Rare, but Addiction Can Happen
Steven Gans, MD is board-certified in psychiatry and is an active supervisor, teacher, and mentor at Massachusetts General Hospital.
The majority of pot smokers do not develop a marijuana addiction, but some smokers do develop all the symptoms of an actual addiction after chronic marijuana use.
Most marijuana users never come close to being addicted to weed. They do not lose control of its use; they generally use the amount they want to use and when they want to use it. When they use marijuana, they get the exact results they expect and intend to get.
The fact that most users never develop an addiction doesn’t mean that it never happens. Some marijuana users will exhibit all the classic behaviors of someone who has an addiction.
The National Institute on Drug Abuse previously reported that about one in seven marijuana users would develop problematic use with the drug. Now the agency is reporting that 30% of marijuana users will develop problems with its use, known as marijuana use disorder.
Users who begin smoking marijuana before they reach the age of 18 are four to seven times more likely to develop a disorder compared with those who wait until after 18 to smoke, according to the NIDA.
Higher Potency Factor
The NIDA also reports that the higher potency of marijuana available today may be another factor in the rising number of people who develop a problem. Marijuana confiscated by law enforcement today contains an average of 9.6% of THC compared to 3.7% in weed confiscated in the 1990s.
Marijuana that is consumed in products that are made from marijuana extract can contain from 50% to 80% THC. Researchers are investigating if higher potency is the reason for an increase in emergency department visits by people testing positive for marijuana.
Marijuana Abuse v. Dependence
There is a difference between marijuana abuse and marijuana dependence. Marijuana abuse occurs when someone continues to use the drug despite negative consequences, such as losing a job, poor academic performance or getting arrested.
Just as with other drug use disorders, people who continue to use marijuana in spite of continued negative consequences, by definition, have a marijuana use disorder.
But, is it an addiction?
Classic Addictive Behavior
Someone who becomes addicted or dependent upon marijuana has a cannabis use disorder, but will also display some of the classic behavioral symptoms of addiction:
- Will begin to lose control, needing increasing larger amounts
- Will spend more time thinking about using
- Will deny claims from those close to him that he has changed
- Substance use will begin to take a central role in life
- Will spend more time and money acquiring more marijuana
- Will become irritable or agitated if they run out
- As negative consequences mount, they will continue to use
Most experts agree that dependence on a substance is accompanied by a build-up of tolerance to that substance, requiring increasing larger amounts, and withdrawal symptoms when someone stops using the substance. Most marijuana smokers do not experience either tolerance or withdrawal.
Most early research into marijuana addiction revealed that marijuana use rarely produced tolerance and withdrawal. But the marijuana that is available today is more powerful than the marijuana of the 1960s, containing higher levels of the active ingredient THC.
Today’s research shows that tolerance does develop to THC and that withdrawal symptoms do occur in some users. Studies of chronic marijuana users who quit smoking show that some experience these withdrawal symptoms:
- Anxiety and insomnia
- Loss of appetite
- Excessive salivation
- Decreased pulse
- Increased mood swings
- Increase in aggressive behavior
Researchers believe that because today’s pot is much more potent it makes it more likely to develop physiologic dependence in some users.
Even if not physically or chemically dependent on marijuana, some users will at the very least develop a psychological dependence upon the drug.
Whether marijuana has become more addictive or not, the number of people seeking treatment for marijuana abuse has increased significantly. According to studies, the number of children and teenagers in treatment for marijuana dependence and abuse has increased by 142% since 1992.
As with most substances of abuse, people who abuse marijuana usually decide to seek help when their use of the drug becomes painful due to increasing negative consequences. Many who seek treatment for marijuana do so due to pressure from family, friends, schools, employers or the criminal justice system.
If you or a loved one are struggling with substance use or addiction, contact the Substance Abuse and Mental Health Services Administration (SAMHSA) National Helpline at 1-800-662-4357 for information on support and treatment facilities in your area.
For more mental health resources, see our National Helpline Database.
The vast majority of marijuana smokers do not develop an addiction, but some do develop all of the symptoms of an actual addiction after chronic use.
Mixing tobacco and marijuana may seem like a good idea, but here’s the dangerous truth about blunts
Researchers believe such smokers would be well advised to consider giving up both drugs at once, rather than one at a time, according to an upcoming study in the journal Addiction.
Clinical trials of adults with cannabis use disorders suggest that “approximately 50% are current tobacco smokers,” according to the report, which was published in the journal Addiction, and authored by Arpana Agrawal and Michael T. Lynskey of Washington University School of Medicine, with Alan J. Budney of the University of Arkansas for Medical Sciences.
“As many cannabis users smoke a mixture of cannabis and tobacco or chase cannabis use with tobacco, and as conditioned cues associated with smoking both substances may trigger use of either substance,” the researchers conclude, “a simultaneous cessation approach with cannabis and tobacco may be most beneficial.”
A blunt is simply a marijuana cigar, with the wrapping paper made of tobacco and the majority of loose tobacco removed and replaced with marijuana. In Europe, smokers commonly mix the two substances together and roll the combination into a single joint, the precise ratio of cannabis and nicotine varying with the desires of the user.
“There is accumulating evidence that some mechanisms linking cannabis and tobacco use are distinct from those contributing to co-occurring use of drugs in general,” the investigators say. Or, as psychiatry postdoc Erica Peters of Yale put it in a press release, “There’s something about tobacco use that seems to worsen marijuana use in some way.”
The researchers believe that this “something” involved may be a genetic predisposition. In addition to an overall genetic proclivity for addiction, do dual smokers inherit a specific propensity for smoked substances? We don’t know—but evidence is weak and contradictory so far.
In the few studies available, for every dually addicted participant who reported greater aggression, anger, and irritability with simultaneous cessation, “comparable numbers of participants rated withdrawal associated with dual abstinence as less severe than withdrawal from either drug alone.” So, for dual abusers, some of them may have better luck if they quit marijuana and cigarettes at the same time. The authors suggest that “absence of smoking cues when abstaining from both substances may reduce withdrawal severity in some individuals.”
In other words, revisiting the route of administration, a.k.a. smoking, may trigger cravings for the drug you’re trying to quit. This form of “respiratory adaption” may work in other ways. For instance, the authors note that, “in addition to flavorants, cigarettes typically contain compounds (e.g. salicylates) that have anti-inflammatory and anesthetic effects which may facilitate cannabis inhalation.”
Studies of teens diagnosed with cannabis use disorder have shown that continued tobacco used is associated with a poor cannabis abstention rate. But there are fewer studies suggesting the reverse—that cigarette smokers fair poorly in quitting if they persist in cannabis use. No one really knows, and dual users will have to find out for themselves which categories seems to best suit them when it comes time to deal with quitting.
We will pass up the opportunity to examine the genetic research in detail. Suffice to say that while marijuana addiction probably has a genetic component like other addictions, genetic studies have not identified any gene variants as strong candidates thus far. The case is stronger for cigarettes, but to date no genetic mechanisms have been uncovered that definitively show a neurobiological pathway that directly connects the two addictions.
There are all sorts of environmental factors too, of course. Peer influences are often cited, but those influences often seem tautological: Drug-using teens are members of the drug-using teens group. Tobacco users report earlier opportunities to use cannabis, which might have an effect, if anybody knew how and why it happens.
Further complicating matters is the fact that withdrawal from nicotine and withdrawal from marijuana share a number of similarities. The researchers state that “similar withdrawal syndromes, with many symptoms in common, may have important treatment implications.” As the authors sum it up, cannabis withdrawal consists of “anger, aggression or irritability, nervousness or anxiety, sleep difficulties, decreased appetite or weight loss, psychomotor agitation or restlessness, depressed mood, and less commonly, physical symptoms such as stomach pain and shakes/tremors.” Others complain of night sweats and temperature sensitivity.
And the symptoms of nicotine withdrawal? In essence, the same. The difference, say the authors, is that cannabis withdrawal tends to produce more irritability and decreased appetite, while tobacco withdrawal brings on an appetite increase and more immediate, sustained craving. Otherwise, the similarities far outnumber the differences.
None of this, however, has been reflected in the structure of treatment programs:
“Emerging evidence suggests that dual abstinence may predict better cessation outcomes, yet empirically researched treatments tailored for co-occurring use are lacking.”
The truth is, we don’t really know for certain why many smokers prefer to consume tobacco and marijuana in combination. But we do know several reasons why it’s not a good idea. Many of the health-related harms are similar, and presumably cumulative: chronic bronchitis, wheezing, morning sputum, coughing—smokers know the drill. Another study cited by the authors found that dual smokers reported smoking as many cigarettes as those who only smoked tobacco. All of this can lead to “considerable elevation in odds of respiratory distress indicators and reduced lung functioning in those who used both.” However, there is no strong link at present between marijuana smoking and lung cancer.
Some researchers believe that receptor cross-talk allows cannabis to modify receptors for nicotine, or vice versa. Genes involved in drug metabolism might somehow predispose a subset of addicts to prefer smoking. But at present, there are no solid genetic or environmental influences consistent enough to account for a specific linkage between marijuana addiction and nicotine addiction, or a specific genetic proclivity for smoking as a means of drug administration.
Agrawal, A., Budney, A., & Lynskey, M. (2012). The Co-occurring Use and Misuse of Cannabis and Tobacco: A Review. Addiction DOI: 10.1111/j.1360-0443.2012.03837.x
"People who smoke them may be reacting to some unidentified mechanism that links the two drugs."