Stronger Marijuana Increases Addiction Risk
Current evidence indicates that the THC content of the marijuana available in the U.S. has increased significantly since the 1980s. Since repeated exposure to THC comes with very real risks for the onset of addiction, the spread of higher potency marijuana could potentially lead to an increase in addiction rates. In a study published in March 2014 in the journal Addiction, researchers from three Dutch institutions investigated the connection between the use of high-potency marijuana and the chances of becoming an addict. These researchers concluded that certain factors related to the use of high-potency marijuana do affect addiction risks.
Like basically all classic substances of abuse, marijuana triggers problems because repeated exposure to the drug can produce long-term changes in the brain’s chemical balance that lead to physical dependence (a term used to describe the brain’s reliance on the presence of a substance to function “normally”). In turn, marijuana dependence is highly associated with marijuana addiction, a condition that appears when a dependent person starts to orient his or her daily routine toward use of the drug and experiences such things as recurring drug cravings, an increasing tolerance to THC’s effects and withdrawal symptoms when THC levels fall below expectations. Roughly one-quarter to one-half of all people who smoke marijuana every day will ultimately meet the criteria for diagnosing cannabis use disorder, a condition that includes all forms of cannabis abuse and addiction, including those linked to the use of hashish or hashish oil.
Some media reports in recent years have suggested that the marijuana commonly available today has a THC content as much as 30 times higher than the marijuana available in the 1970s or 1980s. These reports exaggerate the rise in THC potency, but the trend toward stronger and stronger forms of marijuana is very real. According to research evidence compiled by the National Institute on Drug Abuse, the average THC content of the marijuana available in the 1980s was roughly 4 percent. As a result of widespread changes in growing methods, the average THC content of the drug had increased to 15 percent by 2012. New marijuana users exposed to this much THC may experience a range of unforeseen drug reactions. Regular users of this higher potency marijuana may develop higher risks for addiction; however, they may also adjust their intake patterns and offset the increase in potency by consuming less of the drug.
Increased Risks for Addiction?
In the study published in Addiction, the Dutch research team used an experiment involving 98 heavy marijuana users to help determine if an increase in THC potency can boost the chance that any given person will develop a cannabis addiction. During this experiment, the study participants smoked their own marijuana in a monitored but fairly natural setting. Beforehand, the researchers measured the THC content of each participant’s batch of the drug. While the participants smoked marijuana, the researchers observed their behavior and recorded details such as the number of inhalations for each individual during drug use and the overall volume of the inhaled smoke. Over an 18-month follow-up period, the researchers analyzed the connection between THC potency, specific drug-using behaviors and the chances that any given study participant would ultimately qualify for a cannabis dependence/addiction diagnosis.
After completing their analysis, the researchers came to several conclusions. First, heavy marijuana users do typically reduce their intake of the drug in response to higher THC content. However, compared to users of lower-potency marijuana, they still receive a higher overall dose of THC. When only raw figures are considered, use of higher-potency marijuana does directly increase the odds of developing a diagnosable case of cannabis dependence/addiction. However, the researchers concluded, when all factors are taken into consideration, it appears that only specific habits of high-potency marijuana use play a role in heightened addiction risks. In other words, when users of high-potency marijuana offset drug potency with reduced intake, their addiction risks don’t rise. However, when users of this stronger marijuana don’t use reduced intake to offset drug potency, their addiction risks do rise.
Significance and Considerations
The authors of the study published in Addiction do not state their conclusions in definitive terms. Instead, they note that the results of their work suggest that specific details of high-potency marijuana intake play a bigger role in boosting addiction risks than an increase in the raw amount of THC consumed by a marijuana user on a monthly basis. Future research efforts may help clarify the impact of THC potency on addiction risks.