Is There Really Such a Thing as a “Gateway Drug”?

Young man smoking a joint.

Most people have some kind of understanding of the idea of a gateway drug—drugs that are likely to lead to the use of more dangerous, deadly and addictive drugs. While this seems like a logical and intuitive idea—because how many sixteen-year-olds are going to start out using heroin—there are those who have tried to discredit the concept.

For example, in 2015, Newsweek Magazine made a definitive statement in the headline of an article: “Marijuana is not, repeat, not a gateway drug.”

How could they make this claim?

It has everything to do with the careful balancing act they played with their wording. I want you to understand the clever way they wrote this article.

Here’s a key excerpt from that 2015 article by Miriam Boeri: “The gateway theory argues that because heroin, cocaine and methamphetamine users often used marijuana before graduating to harder drugs, it must be a ’gateway’ to harder drug use. The theory implies that there is a causal mechanism that biologically sensitizes drug users, making them more willing to try—and more desirous of—harder drugs.”

The most important words here are these:


Let’s take a look at the word CAUSAL first. Those who want to refute the idea that the use of marijuana opens the door (or the gateway) to more addictive and deadly drugs generally land on that word CAUSAL. Their counter-argument to the gateway concept is based on the absence of scientific, peer-reviewed studies that the use of a drug like marijuana or alcohol causes a person to go on to use a more addictive drug like cocaine, heroin or methamphetamine.

Science has been unable to prove a causal relationship between these drugs because so many people don’t go on to use and/or become addicted to these more powerful drugs. Maybe that’s a valid claim, maybe it isn’t. Please keep reading because we’ll shed some light on this point.

The second word, IMPLIES, is also important. Is the gateway theory really talking about a biological, causal relationship between drugs typically used in adolescence and harder (more addictive) drugs? Does the theory STATE that there is this kind of relationship or does it IMPLY it? What does the theory say?

To find out, let’s go back a few years to a report on gateway drugs that was written in 1994. That was several years before we found ourselves in the middle of a pervasive marijuana-legalization effort. This report is from the National Center on Addiction and Drug Abuse at Columbia University (CASA).

Cigarettes and alcohol

In a report titled Cigarettes, Alcohol, Marijuana: Gateways to Illicit Drug Use, CASA staff reported on the relationship between these three common “starter” drugs and the progression to use of cocaine. In 1994, cocaine was a much more widely used drug than it has been in recent years so, at that time, it served as a good index for the transition to a more addictive substance.

Analyzing national surveys on drug use, CASA staff found that:

  • 89% of those who used cocaine had used all three gateway drugs first.
  • 90% of youth or adults who had used marijuana had previously smoked cigarettes or consumed alcohol.
  • Youth aged 12 to 17 who had smoked cigarettes were 19 times more likely to have used cocaine than those who had not.
  • Youth aged 12 to 17 who had drunk alcohol were 50 times more likely to have used cocaine.
  • Youth aged 12 to 17 who had smoked marijuana were 85 times more likely to have used cocaine.
  • Youth in this age group who had used all three gateway drugs were 266 times more likely to have used cocaine.

The relationship is clear. Is it CAUSAL? That is, did use of a less addictive drug cause the use of a stronger drug? Scientific studies have not yet been able to prove causation because so many people, both young and old, do not progress to the use of more addictive substances.

Do we need to see scientific proof of CAUSATION to realize that there is a significant relationship between tobacco, alcohol and marijuana use and the use of more addictive substances later on? We can wait for science to try to prove this relationship with some kind of brain science or we can just talk to hundreds of people who became addicted and ask them about their experience.

Here’s the way four people described their own experience with gateway drugs. These were people that did become addicted and needed rehabilitation before they could resume sober lives.

  • “Using marijuana opened the door to other drugs, other people. I stopped going to school. I didn’t have goals anymore. I got introduced to heroin, cocaine and I started using that.”
  • “Once I was smoking pot, I was around people who were doing other drugs. So it made it easier to just do those other drugs. I was like, ’Well, these people are doing it and they seem fine.’ So I did it.”
Young man reaches for pills.
  • “If I was stressed, if I had a bad day or just wanted to relax, I could smoke some marijuana then I could chill out. Tune out of life for a minute. But marijuana after awhile just wasn’t cutting it. I would choose to surround myself with people that I knew were doing other drugs so I could do whatever drugs they were doing. And it progressed from there to an addiction.”
  • “Because of smoking [marijuana] and no consequences really happening, I was open to trying new things. That’s when it started to spiral. I was with a group of people and they had Percocet and offered it to me. My thought process was, ’I’ve smoked weed before, that’s a drug, this is another drug. So this is going to be fine. Just a different feeling.’ Then it spiraled downhill before I even realized what happened.”

By rejecting the idea that the use of alcohol, tobacco and marijuana—and the recent addition to this list, prescription drugs—are gateways to more serious drug use, you might make the mistake of thinking a little drinking or smoking a few joints is harmless. For some people, this will be a fatal mistake. I don’t want that to happen to you.


Karen Hadley

For more than a decade, Karen has been researching and writing about drug trafficking, drug abuse, addiction and recovery. She has also studied and written about policy issues related to drug treatment.