Dr Charles Tannock

Member of the European Parliament for London

Cannabis could Cure

Wall Street Journal - 21st November 2001

One by one, European governments are beginning to reconsider their positions on the recreational use of cannabis. The British government reopened the debate this month by announcing it would reclassify simple possession of the drug so that it will no longer be an arrestable offense. While the recreational use of cannabis remains controversial, I believe that the evidence for medical use is so strong that I will be investigating in the European Parliament whether a EU-wide medical license through the EU's European Medicine Evaluation Agency is legally feasible.

In the U.K. following a recommendation in November 1998 by the House of Lords select Committee to re-allow medical use for the first time since 1971, a number of therapeutic trials are taking place, particularly for multiple sclerosis and pain relief. One such trial, at Hammersmith Hospital in London, is investigating its use as a natural plant extract given sublingually to relieve post-operative pain.

So is cannabis really dangerous? In my previous professional life, as a practicing doctor, I used to oppose any moves to decriminalize its recreational use (due to my own reservations against any kind of drug abuse). But my review of the literature and extensive clinical experience as an inner-city consultant psychiatrist has changed my views. My reasoning is based first on the theoretical grounds that the toxicity of the drug itself is probably smaller than that of aspirin, in terms of lethal dose or therapeutic ratio. Second, it is based on the lack of proven addiction potential cannabis or ability, unlike alcohol, to engender dangerous criminal behavior.

I am particularly skeptical of the findings of the often-quoted Swedish study that allegedly provides evidence that heavy cannabis users have a higher chance of going on to develop schizophrenia, suggesting a causative role for serious mental illness. An equally likely explanation of this finding (if it can be replicated) is that persons with a tendency to schizophrenia are likely to have abnormal personality types and be attracted to all types of drugs. Cannabis in their case may be sought to dampen down some of the unpleasant mood-disorder symptoms of schizophrenia that occur early on, a number of years before the full illness emerges.

In fact, in my years of medical practice I never encountered a true cannabis psychosis in a psychiatrically normal person. Instead I occasionally witnessed the triggering or precipitation of a breakdown in someone with the underlying predisposition to major mental illness (particularly schizophrenia), which is almost invariably due to genetic factors and, less frequently, to other undetected subtle brain damage such as birth trauma.

Sadly, if understandably, many distressed parents of mentally ill offspring are inclined to erroneously blame their children's soft drug taking as the origin and cause of the subsequent mental illness. In fact, considerable scientific doubt exists whether cannabis, in normally consumed doses, is actually hallucinogenic at all for mentally healthy individuals. I certainly found alcohol to be a far more likely and frequent precipitant of dangerous behavior amongst mentally ill patients than cannabis, while alcohol's role as neurotoxin to the human brain (where it can eventually lead to dementia) is, unlike cannabis, undisputed.

As a doctor, I am all too aware of the damage that drugs, and particularly class A drugs such as cocaine and heroin, can inflict on people's lives. Nor can one deny that cannabis has its dangers, especially when taken in excess; as with tobacco, the tar has carcinogenic properties (although the quantity smoked is usually far less) and no doubt the carbon monoxide in the smoke causes heart disease too. (Interestingly, in some countries such as the Netherlands it is deliberately consumed in foods such as cake so as to avoid these recognized dangerous long-term toxic effects).

But the argument that cannabis is a "gateway" to harder drugs is medically unproven. If a statistical relationship exists it may be due to nonmedical factors such as criminal suppliers targeting cannabis-users rather than the general population. That is why the relaxation of laws governing cannabis possession will almost certainly have to be accompanied by much stricter (and enforced) penalties for those dealing in hard drugs and especially for those caught in or nearby schools.

Another major consideration is the fact that the current law in several European countries has become a dead letter given the difficulties in enforcing it. Paradoxically, I believe there are now more cannabis users per capita in the U.K. than in Holland, where its use has been decriminalized.

The U.K. had also become increasingly out of step with other European jurisdictions in the theoretical severity of the sanctions that could be applied (up to five years in jail) to otherwise law abiding people who have to rely on criminal suppliers to indulge their habit. This perversely facilitates dealers who have an incentive to get users hooked on more addictive and dangerous drugs. Nonetheless, as Conservative politician Peter Lilley has rightly pointed out, the U.K. government's limited proposals, which prevent the legal sale of cannabis, will still leave people having to get their softer drugs from pushers who deal in hard drugs - unless, of course, they are prepared to grow their own.

No one can pretend that this is an easy debate. I do not myself use cannabis and would not recommend its recreational use to anyone else. However, we must acknowledge that, despite its illegal status, as many as 40% of young British people have reportedly used cannabis, and that simple prohibition may not be the best solution. Moreover, many young people regard it as hypocritical for those who use and abuse alcohol and tobacco to restrict them in their use of cannabis. This, in turn, has helped to encourage a disrespect for the law and to alienate them from the political process, which itself should be a cause for concern.

That said, those advocating liberalization should be prepared to accept that if governments introduce reforms that only serve to worsen the situation, then those reforms should be reversed. However, in Belgium, where I work, and following experience in Holland, Spain, Italy and Portugal, cannabis was quietly legalized last year with no fuss, and, contrary to some dire predictions, there has been no epidemic of hard drug use, visible increase in street cannabis consumption or rise in violent drug related crime, giving at least some cause for optimism.