Pubdate: Mon, 26 Nov 2001 Source: New Scientist (UK) Copyright: New Scientist, RBI Limited 2001 Page: 54 Contact: http://www.newscientist.com/ Details: http://www.mapinc.org/media/294 Authors: Robert Sharpe, Maia Szalavitz, Don Churms, Galen Ives, Rod MacQueen, Dan Grubbs Note: These were the lead letters in the letters column, with Robert Sharpe's given a prominent shaded "side-bar" area at top of page. Referenced: http://www.mapinc.org/drugnews/v01/n1866/a04.html Referenced: http://www.mapinc.org/drugnews/v01/n1910/a03.html DOPE ON DOPE You're absolutely right. Even if every myth about cannabis causing "reefer madness" were true, the harm caused by the drug would not justify sending users to prison (3 November, p 3 and p 12). The zero tolerance approach both victimises users and harms society at large. Prisons transmit violent habits and values rather than reduce them. Most non-violent drug offenders are eventually released with dismal job prospects due to their criminal records. Turning cannabis smokers into hardened criminals is a senseless waste of tax dollars. Hopefully the common sense coming out of Britain will rub off on the US. More Americans were arrested for cannabis in 2000 than all violent crimes combined. For a drug that has never been shown to cause an overdose death, the amount of resources used to enforce cannabis prohibition is outrageous. The effectiveness of zero tolerance is dubious at best--despite harsh penalties, the US has higher rates of cannabis use than any European country. Sooner or later Britain is going to have to take the next logical step. Decriminalisation acknowledges the social reality of cannabis use and frees users from the stigma of criminal records. What's really needed is a regulated market with enforceable age controls. Separating the hard and soft drugs markets is critical. As long as cannabis distribution remains in the hands of organised crime, consumers will continue to come into contact with hard drugs. Robert Sharpe, The Lindesmith Center Drug Policy Foundation, Washington, DC - ----- David Fergusson was quoted as saying that he "can't explain away" the correlation between marijuana use and subsequent hard drugs use found in his study in New Zealand. But the hardly radical Institute of Medicine, part of the US National Academy of Sciences, discredited the "gateway theory" that marijuana leads to hard drugs use in its recent report to Congress on the potential dangers of medical marijuana. The report said, "There is no conclusive evidence that the drug effects of marijuana are causally linked to the subsequent abuse of other illicit drugs." Even Fergusson's paper qualifies his comments more than your reporter suggests. His abstract ends with the statement: "Findings support the view that cannabis may act as a gateway drug that encourages other forms of illicit drug use. None the less, the possibility remains that the association is non-causal and reflects factors that were not adequately controlled in the analysis." Let me suggest just one major confounding factor. Perhaps some people simply like taking drugs, and some of those people like to take them more often than others and like to try many different ones. This could explain why two-thirds of cannabis smokers don't use other drugs--and why heavier smokers are more prone to use other drugs--better than any pharmacological idea about pot changing the brain. Occam's razor needs to be applied with particular sharpness to research on illicit drugs, which tends to serve political agendas far more than scientific ones. Maia Szalavitz, New York - ----- You report that: "Although two-thirds of cannabis users [in the New Zealand study] did not progress to other illicit drugs, nearly all hard-drug users started off on cannabis." Could it not be that most teenagers--and also most adults--use some sort of mild drug, such as cannabis, nicotine and alcohol, and that a smaller subset of people progress to harder drugs? The causal relationship for cannabis may appear a little stronger because its illegality (and reputation) probably keeps some potential users away, but I suspect most hard drug users also began smoking cigarettes and drinking alcohol. Don Churms, Charlottesville, Virginia - ----- I was sorry to see you fall for an old statistical (or philosophical) chestnut. "The link is undeniable," you say of the New Zealand study that showed 99 per cent of hard drug users started with cannabis. An unpublished study of my own reveals that 100 per cent of all drug users and alcoholics started on milk, and by the same logic it is clearly high time some action was taken to restrict access to this dangerous white liquid. Galen Ives, Sheffield - ----- My experience as a clinician, for what it's worth, is that most cannabis users who come to our attention--a minority of users who experience trouble with the drug--have many other problems. This is consistent with the literature. As recently as last week, at the Australian Professional Society on Alcohol and other Drugs Conference in Sydney, we heard of the high rate of association between problematic cannabis use or "dependence" (I'm never sure what that is) and other problems, but no evidence of a causal link. There was a call for more treatment for cannabis misuse, but no evidence to suggest that this would work any better than treatments of distress from violence, abuse, mental health issues or chronic hopelessness. Given that we have successful and cost-effective treatments for anxiety and depression, and given that the benefits of early intervention have been proven, this seems an unfortunate oversight. When users' other problems are addressed, often by quite brief interventions, cannabis use rarely continues to be an issue. This, again, is consistent with results from studies of both laboratory animals and humans. But it seems easier to keep bagging cannabis, revealing the triumph of dogma over evidence. Susan Greenfield, the Oxford pharmacologist who opposes the legalisation of cannabis, seems to have fallen into this trap. Prohibition increases both the cost of this substance and the anxiety associated with obtaining and using it, which often makes these people's problems worse. But it does not seem to prevent or reduce use. What should an intelligent, evidence-based policy look like--surely not more of the same? Rod MacQueen, Orange, New South Wales - ----- I would like to refer you to a study done on the gateway effect in the Netherlands. "Keeping off, stepping on and stepping off: the steppingstone theory reevaluated in the context of the Dutch cannabis experience" by Stephen Sifaneck and Charles Kaplan (Contemporary Drug Problems, vol 22, Autumn 1995). They found that the so-called gateway effect is more likely due to criminalisation because of interaction with dealers who often sell harder drugs as well, and that, as your reporter Claire Ainsworth stated, separating markets does appear to weaken the gateway effect. This study also found that alcohol abuse was more likely to precede hard drug use than marijuana. For example, alcohol abuse preceded 94 per cent of heroin use in the study population, in contrast to 30 per cent having used marijuana. So can we really say cannabis is THE gateway drug? Dan Grubbs, Address supplied - --- MAP posted-by: Richard Lake