Contact : EDPLetters@ecn.co.uk
Comment : Dr. Ian Gibson is former Dean of Biology at the University of East Anglia and now Labour MP for Norwich North.
Ian Gibson MP, House of Commons, London, SW1A 0AA
Time to unlock the secrets of cannabis
Cannabis has for years been branded an illegal and harmful substance but Labour MP Ian Gibson says the Government should take a fresh look at the drug and its uses.
In a recent interview on the Breakfast with Frost programme, Home Secretary Jack Straw said: "The evidence is strong about cannabis. If you look at the journals, it's all there, about the long-term (detrimental) effect of cannabis."
Mr Straw's remarks demonstrate how the whole cannabis debate has become highly polarised with the public being presented with totally-opposite arguments on the health effects of cannabis.
Some advocates of the decriminalisation of cannabis claim that the drug is "safer than aspirin" while others adopt Mr Straw's line and argue that the drug is a deceptively-dangerous substance. It may seem obvious that policy on the use of cannabis should be based on scientific evidence, factual information and common sense.
However, an in-depth look at the scientific evidence demonstrates that the certainties on which Mr Straw bases his argument, and the Government's position, are difficult to support.
The tragic death of a young Norfolk girl was linked to the drug Dianette, which is a contraceptive drug also prescribed for the treatment of acne. Up until January this year, six deaths were attributed to adverse reactions to this substance.
Yet hundreds of thousands of people have benefited from taking Dianette.
This is a stark illustration that there is no such thing as a totally safe drug, be it for medical or recreational use. Dianette, like so many prescribed drugs, presents a small risk of side effects and highlights the need for ongoing research and risk / benefit analysis.
So what does science tell us about cannabis? A technical report, which was conducted for the United States Toxicology programme, looked at the toxic effect of 1-transdelta9-tetrahydrocannabinol (THC, which is the major psychoactive component of cannabis).
The study revealed no evidence of carcinogenic activity in rats and only equivocal evidence in mice. Furthermore, the report found no human epidemiological or case reports linking THC with cancer.
There is little doubt that cannabis is significantly less likely to cause cancer than tobacco, a drug sold over the counter in the House of Commons. However, this and many other studies demonstrate a less favourable picture of the neuro-behavioural effects of THC, which reveal problems with mood swings, impairment of short-term memory and altered perception of visual and auditory stimuli.
Other detrimental findings recorded in several different studies on chronic cannabis users included problems with reduced sperm count and a decrease in T cells and interferon levels which effect the ability of the body's immune system to ward off infection.
Conversely, other studies have reported that cannabis smoking has no effect on the immunity system, or that cannabis is in fact a slight stimulant to the immune system.
Cannabis has been used successfully for a number of applications. Theses include reducing pain and inflammation; lowering the intraocular pressure in glaucoma; relieving the nausea associated with chemotherapy; stimulating appetite; calming diarrhoea; and relief from muscle spasm.
It is, however, debatable as to whether the medical benefits of cannabis have been replaced by more sophisticated drugs which have been developed in recent years.
For example, the use of beta-adrenoceptor blockers or pilocarpine to treat glaucoma has reduced interest in the use of THC for this application.
Cannabis still ahs a lot of pharmaceutical secrets for scientists to unlock and it is crucial that the stigma surrounding this substance is not allowed to prejudice further research.
Given what we know about the toxicity of tobacco, I have some sympathy with Mr Straw when he said: "If we were to start from scratch we would certainly say that tobacco is a bad idea... we would, I think, have banned it."
HOWEVER, it was his remarks about alcohol which I believe inadvertently point us in the direction of a sane and workable drugs policy.
Mr Straw said: "Alcohol, it's a drug, yes, it is a drug but it is one we are used to dealing with."
Of course the misuse of alcohol is a problem that deserves our attention, indeed the lethal cocktail of alcohol and the motor car has lead to the deaths of many thousands in road accidents, and one could argue that factor alone makes it more dangerous than cannabis.
However, it is true to say that the vast majority of people who take alcohol do so without causing medical or social harm. Most people in society have learned to use a potentially-dangerous substance, which shares certain negative effects with cannabis, in measures which are both tolerable and in some ways efficacious.
There is a strong case for treating the smoking of cannabis in much the same way as we treat the consumption of alcohol.
The commonly-articulated goal of a "drug-free Britain" is a highly desirable one - however, it is no more achievable than a crime-free Britain" or indeed a "risk-free" drug.
Of course the Government should design policies aimed at reducing the use of drugs, but these policies must be flexible, allowing all the agencies to tailor their approach to suit individual drug cases.
Heavy-handed methods could lead to users avoiding seeking help through fear of Draconian penalties.
President Jimmy Carter said: "Penalties against a drug should not be more dangerous to the individual than the use of the drug itself; and where they are they should be changed. Nowhere is this more clear than in the laws against the possession of marijuana."
President Carter's words were in response to the Shafer Commission which in the early 70s conducted a massive survey of drug use in the USA.
I believe our Government should commission a similar, but broader-based study of drugs and drug use. The conflicting scientific information on cannabis suggests that the commission should include an extensive review of the science in its remit.
I hope that the House of Lord's inquiry, which is to reopen the whole question of continuing to outlaw cannabis, acts as the catalyst needed to bring about this wider debate.
When Mr Straw next trawls through the journals he will find as many different research papers as there are opinions, but through the fog of debate he will find one fact stands out: pumping more and more money into law enforcement has not made the drug problem go away, and it probably never will.
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