There has been substantial debate regarding whether marijuana use can be risky and possibly act as a gateway to more powerful drugs, such as heroin. Gateway drugs are substances believed to be habit-forming and may lead to experimentation with other substances.
The gateway drug theory posits that marijuana is likely to be used before an individual progresses to harder drugs, such as opioids, cocaine, or meth. Moreover, using a drug like marijuana may increase the desire to use other drugs, resulting in more use. Also, when an individual who uses marijuana associates with others who also do, the likelihood they will be exposed to other substances increases. In other words, more potent drugs may become available.
This theory is based on the notion that those who use substances gradually advance through escalating stages. These stages begin when an individual uses legal, socially-accepted substances, such as nicotine and alcohol. Later, they start to experiment with relatively mild drugs, such as marijuana. Eventually, they advance to the use of more potent drugs, such as heroin.
However, research has challenged this idea and revealed that many individuals do not follow this series of steps.
How Does the Gateway Hypothesis Work?
Supporters of this hypothesis for drug and alcohol use point to two underlying conditions that could lead to certain substances making an individual more vulnerable to using other substances.
1) A gateway drug would presumably affect brain neuropathways.
Studies have shown that animals that begin to use certain substances early in life are at an increased likelihood of developing addictive behaviors related to other substances. When these animals are examined postmortem, findings show that some brain regions are altered. Also, the results of these experiments are comparable to observational data witnessed in humans.
2) There is an interaction between genetics and the environment.
Two studies in humans found a significant genetic component related to drug abuse. This component was shown in those who abuse multiple substances. Therefore, certain intrinsic factors may contribute to altering neuropathways and account for the gateway hypothesis.
Researchers who study drug abuse have identified several environmental and individual factors associated with polysubstance abuse. Thus, the gateway theory suggests that the interaction of intrinsic factors with personal experience may lead to circumstances that support its hypothesis.
Evidence That Supports the Gateway Drug Theory
Some research implies marijuana use is likely to precede abuse and addiction to other substances. For instance, one study revealed that adults who reported using marijuana during the first phase of the survey were more likely than marijuana-free subjects to develop an alcohol use disorder within three years.
Marijuana use has also been linked to other substance use disorders, such as nicotine addiction. But there is more to be considered. Many factors may contribute to substance abuse, such as the following:
- Community and neighborhood environment
- Level of parental supervision in youth
- Unique individual characteristics, including genetics and experiences
Also, an individual who uses marijuana may be influenced by the enjoyability of their first exposure and whether they believe that marijuana use is risky or not.
Evidence Against the Gateway Drug Theory
A 2016 study focused on the link between gateway drug use in the early adolescent years and drug use later in life. They found that, indeed, this behavior was indeed strongly linked to marijuana and illicit drug use, including cocaine, later in the teenage years.
However, these relationships were inconsistent in adulthood. Investigators reported that “a history of higher depressive symptoms was associated with higher frequencies of psychoactive drug use over time.”
They also reported that “users of mental health services in adolescence were less likely to use drugs in older adolescence and in adulthood.”
Is Marijuana a Gateway Drug?: Conflicting Research
Overall, studies focused on the gateway drug theory has yielded conflicting results. While some research does support this idea, others bring it into question. For example, one study from the RAND Corporation failed to identify a meaningful gateway effect related to marijuana use.
However, RAND theorized another possibility, stating there is “some support for such a ‘common-factor’ model in studies of genetic, familial, and environmental factors influencing drug use.”
Investigators also reported that marijuana use often heralds the use of harder drugs, primarily because marijuana is more available earlier in life than, say, heroin or cocaine. Nevertheless, this may be a case in which correlation does not equal causation.
Finally, a 2017 review found moderate evidence of an association between marijuana use and the development of substance dependence or substance use disorder related to alcohol, tobacco, and other psychoactive substances. However, it did not lead to sufficient evidence for a direct causal relationship.
Is Marijuana a Gateway Drug?: Other Problems
Those who support this theory may not consider the widespread availability of certain legal substances, such as alcohol. Also, both medical and recreational marijuana legalization has become increasingly prevalent throughout the United States.
Suppose an individual consumes alcohol or ingests marijuana. In this case, they are likely to do so earlier in life because these substances are more easily accessible than harder drugs, such as heroin or cocaine. Of note, few individuals contend that caffeine or prescription drugs even used as directed can prompt one to use other substances.
Aside from potential effects on the reward pathway and an increase in dopamine, there is little reason to assume that the use of one substance would serve as a gateway to others. Different types of drugs act on different brain receptors that are responsible for addiction. For example, it is reasonable that an individual dependent on oxycodone would progress to heroin because the same opioid receptors are affected. However, marijuana use interferes with cannabinoid receptors, which are not at all involved with opioid use.
Finally, those who support the gateway drug theory use may use statistics misleadingly. For instance, these supporters may point to a high percentage of heroin users using marijuana in the past. They may contend that this suggests a high rate of marijuana users progress to heroin abuse, which is not correct.
Even if it were confirmed that all of those who abused heroin had used marijuana in the past, it would not logically follow that marijuana was the causative agent in their progression to heroin use. It also does not show that all marijuana users or even a significant percentage of them later abused heroin.
So, is marijuana a gateway drug? Although marijuana use tends to come before the use of other drugs, this, in no way, indicates that an individual who smokes marijuana will progress to harder drugs. There are many factors involved, and it could simply be that an individual who uses one drug may gravitate toward substance use of all types.
Treatment for Drug Addiction
Although the gateway drug theory is still under considerable debate, there’s no question that drug abuse in and of itself can become problematic and may require professional treatment.
Just Believe Recovery center addiction programs are comprehensive, evidence-based, and include essential services, such as behavioral therapy, group support, counseling, art and music therapy, and more. We provide those we treat with all of the tools they need to recover fully and foster the healthy and satisfying lives they deserve.