Marijuana and the Gateway Hypothesis

Smoke pot, shoot smack?

The Great Gateway Hypothesis has had a long, controversial run as a central tenet of American anti-drug campaigns. As put forth by Denise B. Kandell of Columbia University and others in 1975, and refined and redefined ever since, the gateway theory essentially posits that soft drugs like alcohol, cigarettes, and marijuana—particularly marijuana—make users more likely to graduate to hard drugs like cocaine and heroin. What is implied is that gateway drugs cause users to move to harder drugs, by some unknown mechanism. The gateway theory forms part of the backbone of the War on Drugs. By staying tough on marijuana use, policy makers believe they will have much broader impacts on hard drug use down the road.

This notion is virtually an article of faith in the drug prevention community. It just feels intuitively right: Scratch a junkie, and you’ll find a younger, embryonic pot smoker or furtive teenage drinker. Ergo, prevent teen pot smoking, and you will block the blossoming of a multitude of future hard drug addicts.

For years, the gateway hypothesis has had its share of contentious opponents. The countervailing theory is known primarily as CLA, for Common Liability to Addiction, the genetically based approach that lines up with the notion of addiction as a chronic disease entity. Most genetic association studies have failed to record risk variations for addiction that are specific to one addictive drug. Writing last year in Drug and Alcohol Dependence, Michael M. Vanyukov of the University of Pittsburgh, along with a large group of prominent addiction researchers, argued that the gateway hypothesis is essentially a form of circular reasoning. “It is drug use itself that is viewed as the cause of drug use development,” they write. The staged progression from one drug to another “is defined in a circular manner: a stage is said to be reached when a certain drug is used, but this drug is supposed to be used only upon reaching this stage. In other words, the stage both is identified by the drug and identifies the drug. In effect, the drug is identical to the stage.”

The researchers reject any causal claims on behalf of the gateway hypothesis and insist there is no necessary usage of soft drugs at an earlier stage to pave the way for hardcore addiction, however watertight the idea might sound. The high correlations are “artifactual,” they argue, “because they are estimated among hard drug users, without taking into account the large population of those who try or even habitually use marijuana but never transition to harder drugs.” A common cause, such as an underlying vulnerability to all drugs of abuse, seems more to the point, they insist. There is nothing out there to suggest that “these stages are either obligatory or universal, nor that all persons must progress through each in turn… the initiation order is frequently reversed even for the licit-to-illicit sequence.” There is only one stage that universally precedes hard drug use, they argue. And that is non-use. “It is the non-use then, which should be the actual gateway condition.”

The leading theory supporting the gateway hypothesis is that some as yet undetermined mechanism of “sensitization” occurs after using a gateway drug. But there is no science supporting this notion. “If sensitization does occur,” the researchers say, “it is equivalent to an increase in individual liability at the level of neurochemical mechanisms of addiction.”

The paper in Drug and Alcohol Dependence notes that in Japan, where marijuana is used by less than 5 percent of young people, “cannabis is not used first by a staggering 83.2% of the users of other illicit drugs, thus violating the gateway sequence.” Japan also handily knocks down the idea of alcohol as a gateway drug: Whereas the prevalence of aldehyde dehydrogenase deficiency—the so-called alcohol flush reaction—keeps many Asians from drinking alcohol regularly, this does not correlate with lower rates of non-alcohol substance use in that population.

All of this would seem to put the last nail in the notion that “involvement in various classes of drugs is not opportunistic but follows definite pathways,” as Vanyukov et. al. put it. Common sense seems to be ahead of official drug policy in this regard. According to Maia Szalavitz, writing at TimeHealthland, “only 38% of people now agree with the idea that ‘for most people, the use of marijuana leads to the use of hard drugs’ compared to 60% in 1977.”

For proponents of common liability to addiction models, any staged sequencing of drug use is considered opportunistic and trivial. Which, interestingly, is how many addicts tend to view the gateway theory. But the idea of marijuana or alcohol as a gateway drug just feels intuitively correct to many people. Part of the problem is chronological. “At the relatively distal time when genetic relationships are usually evaluated,” the authors maintain, “the role of this early-acting factor may be as difficult to detect as it is to find a match that started a forest fire.” Your genetic endowment is with you from birth, while your first drink or toke of marijuana does not happen for a decade or two. Individual environmental conditions, from epigenetic changes to a move to a different neighborhood, determine how it will play out down the road, but these factors are mostly invisible at the time of addiction.

All of this matters from a policy point of view, because research “may be hindered or misdirected if a concept lacking substance, validity and utility is accorded prominence.” However, even when the gateway hypothesis is taken as a given, different legal and social outcomes are still possible. The best example is found in The Netherlands. The prevailing belief there is that “the pharmacological effects of cannabis increase adolescents’ likelihood of using other drugs,” as stated  by Wayne Hall, a professor of public health policy at the University of Queensland, Australia. Writing in Addiction, Hall says that drug policy analysts in The Netherlands have argued that the fabled gateway “is a consequence of the fact that cannabis and other illicit drugs are sold in the same black market; they have advocated for the decriminalization of cannabis use and small retail sales in order to break the nexus between cannabis use and the use of other illicit drugs.”

This “Marijuana Shop” approach may have direct relevance in the U.S., in the wake of cannabis legalization in Washington and Colorado. James Anthony, a professor of epidemiology at the Bloomberg School of Public Health at Johns Hopkins, writes about the real-world ramifications of the cannabis shop in Addiction: “Do we actually achieve a near-term delay in the time to a young person’s first chance to try cocaine or heroin... [or] do we run the risk of accumulating more cases of dependence on marijuana, or other hazards attributable to non-essential marijuana use?

The true gateways to addiction appear to be behavioral. As part of their genetic endowment, budding addicts are far more likely than other people to exhibit behavioral “dysregulation” when young, in the form of disinhibition, impulsivity, and antisocial behaviors. More than half of all addicts are co-morbid, meaning they also have a psychological or behavioral disorder in addition to addiction. Further analysis of this fact would seem to be a more fruitful research avenue than simply prodding at alcohol or marijuana in an effort to uncover their chemical “secrets” for compelling future drug use.

Photo Credit: http://tcktcktck.org/ Creative Commons: Randi Shooters, 2010

The Economics of Legalization

British study sees annual savings of $20 billion.

Legalizing heroin and cocaine would save Great Britain as much as $20 billion a year, a British drug reform group claims in a 50-page report issued this week. The Transform Drug Policy Foundation said the savings would come primarily in the form of reductions in the cost of government enforcement.

The report, “A Comparison of the Cost-effectiveness of Prohibition and Regulation,” purports to be the first cost-benefit analysis ever undertaken with respect to drug prohibition in Britain. According to an analysis in the Drug War Chronicle, “the British government has relied on mere assertion to justify maintaining prohibition and to argue that the harms of legalization would outweigh its benefits.” The drug reform foundation examined criminal justice, drug treatment, crime, and other social costs, and concluded that “a regime of regulated legalization would accrue large savings over the current prohibitionist policy.”

The Drug War Chronicle reported that the reform group “postulated four different legalization scenarios based on drug use levels declining by half, staying the same, increasing by half, and doubling. Even under the worst-case scenario, with drug use doubling under legalization, Britain would still see annual savings of $6.7 billion. Under the best case scenario, the savings would approach $20 billion annually.”

Specifically, the report says that “even in the highly unlikely event of heroin and cocaine use increasing 100%, the net benefit of a move to regulation and control remains substantial. The economic benefits of regulation identified are also of a magnitude to suggest that even with significant margins of error we can assume that legally regulated markets would deliver substantial net savings to the Treasury and wider society.”

In addition, the report notes that “The Government has also repeatedly failed to acknowledge that prohibition is a policy choice, not a fixed feature of the policy landscape that must be worked within, or around.”

“The most striking conclusion from the analysis of current costs,” the report concludes, “is that prohibition of drugs is the root cause of almost all drug-related acquisitive crime, and that this crime constitutes the majority of drug-related harms and costs to society.”

The full report from the Transform Drug Policy Foundation can be downloaded in PDF format here.

Photo Credit: http://thewhitedsepulchre.blogspot.com

addiction drugs

McCain on Drugs

Full speed ahead on the Drug War.

One issue largely missing in action during the presidential campaign has been the Drug War, and all the policy implications for addiction treatment that go with it. Our thanks go out to OnTheIssues blog for compiling the admittedly skimpy record of public statements about drug policy by both candidates. In this post, we examine the on-the-record views of Republican candidate John McCain.

In his long career in the U.S. Senate, John McCain’s support for the Drug War has never wavered. Campaigning for president in 2000, McCain’s positions were the most hawkish of the four major candidates, the Boston Globe reported. “He wants to increase penalties for selling drugs, supports the death penalty for drug kingpins, favors tightening security to stop the flow of drugs into the country, and wants to restrict availability of methadone for heroin addicts.”

This latter position was embodied in the “Addiction Free Treatment Act” that McCain introduced in the Senate in 1999, which called for defunding any drug program that used methadone, unless the program followed a restrictive set of guidelines.

McCain has criticized the former Clinton administration for going “AWOL on the war on drugs,” and has pushed tirelessly for greater military assistance to drug-exporting nations like Columbia.

In more recent activity, Senator McCain sponsored a a 2005 bill, “The Clean Sports Act,” mandating drug testing in all major professional sports leagues. And in 2006, McCain signed on to the “Safe Streets Act Amendment,” which called for federal grants to Indian tribes to fight methamphetamine addiction.

This year, “McCain met with Mexican President Felipe Calderon to discuss immigration, trade and the recently passed Merida Initiative, a $400 million U.S. aid package to help Mexico fight an increasingly bloody drug war that has claimed more than 1,800 lives this year.”

“Drugs is a big, big problem in America,” McCain said in a fact-finding trip to Columbia in July. “The continued flow of drugs from Colombia through Mexico into the United States is still one of our major challenges for all Americans.”

McCain’s response last year to a New Hampshire police officer’s question about the failure of the Drug War does not bode well for the prospects of responsible changes in drug awareness and addiction treatment in a McCain administration: “Look, I've heard the comparison between drugs and alcohol. I think most experts would say that in moderation, one or two drinks of alcohol does not have an effect on one's judgment, mental acuity, or their physical abilities. I think most experts would say that the first ingestion of drugs leads to mind-altering and other experiences, other effects, and can lead over time to serious, serious problems."

A search of the McCain-Palin campaign website for the term “drug war” came up empty.