Cannabis — The Truth

By Mary Brett, Head of Health Education, Dr.Challoners Grammar School, Amersham. Bucks.

Paper presented at the Maxie Richards Foundation Conference Glasgow Oct 2003.
Cannabis or marijuana, is our commonest illegal drug, currently used in Britain by around 3.2 million people. Most of them are totally unaware of its damaging effects, especially on the brain.

There are now in excess of 15,000 scientific papers on cannabis. None of the ones I have read say it is a safe drug, and I am assured it is the same for the rest.

We need to know how this damage is caused, and will start with the cells of the brain. Messages pass along the nerve fibres as minute electrical impulses and cross the gap, the synapse, between nerve cells in the form of chemicals called neurotransmitters. These are the brain’s natural drugs and there are dozens of them Each neurotransmitter molecule has a particular shape that fits into its own receptor site on the next cell, as a key fits into a lock.

The mind-altering drugs that people take operate at these synapses. They either mimic the neurotransmitter by shape, increase the rate at which they are released block them or prevent them from being re-absorbed. They take control point out to my pupils that no person can do that, no parent, no teacher or friend. But drugs can.

The psychoactive ingredient in cannabis is a substance called tetrahydrocannabinol, THC for short. It mimics a neurotransmitter called anandamide, from the Sanskrit word, ananda, which means bliss, Receptor sites for anadamide, and therefore THC, exist in many regions of the brain and in other organs of the body. So the actions of cannabis are many and varied.

In the brain, CBI receptors are in the cerebral cortex. In the sensory areas, sound and colour perception are distorted. Muscle coordination and psychomotor skills like driving are impaired in the motor areas, judgement, reasoning and logical thought are also affected. They are also present in the hippocampus where memory and the appreciation of time and space are situated, There are other areas with receptors, but the lack of them in the brain stem which controls automatic functions like respiration, is thought to explain the absence of overdosing. In the rest of the body the receptors are called CB2 receptors.

But it is in .the limbic region of the brain, a circular area in the centre, which suffers the greatest impact from cannabis. This is the seat of the emotions, and its activity determines our moods, whether we are happy or sad anxious or peaceful. Anxiety, depression, panic attacks and even paranoia can be triggered if it is disturbed. It also houses the ‘pleasure ‘or ‘reward’ system. Many drugs affect this area to give a high e.g. cocaine, ecstasy, amphetamines, alcohol and nicotine. Cannabis is no exception. The reason people give for taking cannabis is to get a high or a feeling of euphoria. All these drugs release the neurotransmitter, dopamine. However, THC acts on the CB1 receptors more strongly and for a longer time than anandamide so the effects are enhanced, THC has to be entirely eliminated from the body whereas anandamide is quickly recycled.

One experience of a high leads to another and another. Tolerance develops, receptors need more stimulation and more are produced. Dependence occurs, both psychological and physical. Withdrawal symptoms have been seen, shaking, insomnia, irritability, anxiety and aggression. Not so dramatic as the ‘cold turkey’ of heroin withdrawal since the fat-soluble cannabis remains so long in the body.
Fifty per cent of the THC from a joint will still be there five to six days later and ten per cent after a month, traces can be detected in the hair and urine for weeks after that. Compare this with water-soluble alcohol which disappears at the rate of one unit an hour, the amount in half a pint of beer a glass of wine etc.

In September, 2002, out of the six million drug addicts in the United States, sixty per cent were dependent on cannabis, and more youngsters were being treated there for marijuana dependence than for alcohol. An Australian researcher, Professor Wayne Hall, estimates that of those who ever try cannabis, ten per cent will become addicted, roughly the same as for alcohol.

There is no foolproof cure for any type of addiction.

The effects on the brain are not limited to addiction. People don’t always get the desired euphoria they are seeking. The most common adverse effect is anxiety or even panic. Symptoms can range from restlessness to loss of control to paranoia and fears of impending death. Although these are usually short-lived, occasionally they persist for several weeks.

An American paper in 2001 using nearly 2,000 participants, reported a four-fold increased risk of major depression. The same risk factor emerged in an Australian study of daily teenage female users. A paper in the British Journal of Psychiatry May 2002, found the increased risk for depression was 26 times in teenagers who use cannabis, alcohol and tobacco.

Acute psychosis can occur. A ten-year experiment with decriminalization in Alaska was terminated in 1991 by a public referendum after over 2,.000 people had to be hospitalized and treated in the previous two years for cannabis psychosis. The four to six week treatments were carried out at the taxpayers expense, fuelling anger and resentment. I personally know of six people in some way connected with my school, who have young relatives or friends who have become psychotic due to cannabis use.

A friend of mine lost a son to drugs 2 years ago. He had started using cannabis at the age of fifteen at his public school. And as so often happens progressed through all the other drugs and spent the last few years of his life in care homes and psychiatric institutions. He died of a particularly pure dose of heroin at the age of 45. Shortly before he died, he told his mother he could handle any drug now except cannabis. It made him paranoid and terrified him.

Swedish studies which followed the progress of over 50,000 conscripts, aged eighteen to twenty-five, over fifteen years, discovered that the risk of developing schizophrenia was increased by a factor of six for those who had used cannabis more than fifty times. This was when the concentration of THC was much lower than it is today. In the sixties, the average THC content was 0.5%, now at 5%, it is ten times stronger. Skunk and nederweed, selectively bred varieties from Holland can have THC contents of anything from 9% to 27%. This is a very different drug from the one that fuelled the ‘hippy’ generation.

Other studies have confirmed these findings of mental illness, and one from New Zealand by Dr Louise Arsenault of the Institute of Psychiatry in London in 2002, found a correlation with cannabis and violence. Young males were five times more likely to be violent than non-users, the increased risk for alcohol was three. So much for the cry of the pro-legalisers that youngsters are better off stoned and peaceful than drunk and violent. Whether cannabis actually causes schizophrenia is still to be discovered, but it certainly triggers and exacerbates the condition in vulnerable people. It is interesting to note that increased dopamine activity is implicated in schizophrenia, and other dopamine releasing drugs like amphetamines and cocaine can cause a schizophrenic psychosis. Could this give us a clue as to how cannabis operates?

In a Swedish investigation into suicides, users of alcohol, amphetamines and heroin were compared with marijuana users. More cases occurred in cannabis users than in any other group and the methods used were more violent, No other group jumped from high buildings or murdered others before taking their own lives. There have been several tragic tales in the press in the last year or so, of young people committing suicide after taking cannabis. Maybe people don’t die of an overdose, a common cry of the pro-legalisers but in 1999, in the United States, out of 664 marijuana related deaths, in 187 of them the only drug involved was marijuana.

There is increasing suggestive evidence, both from animal experiments and scans of the human brain, that some cells may die. Brain cells are never replaced. Permanent brain damage is a distinct possibility. It would be slow, subtle, insidious but cumulative.

High densities of CB1 receptors in the cortex and hippocampus cause concentration and the learning and memory processes to be badly impaired. The persistence of THC in the membranes for a long time, compounds the problems. As a schoolteacher, this is the area that causes me most concern.

Even on one or two joints a month, a cannabis personality develops. Users become inflexible, can’t plan their day properly, their problem-solving skills deteriorate, they can’t take criticism and they feel misunderstood. School grades take a nosedive and they often miss out on their chosen university places. At the same time they are lonely and miserable, Trying to talk sense to them becomes a futile exercise. Few children, using cannabis even occasionally, will achieve their full potential.

A few years ago, a former pupil came to see me. He was in his last year of a degree in pharmacology and wanted to do his dissertation on cannabis. Having been a user of cannabis while at school, he had only just managed to scrape into university with C and D grades Most of his friends didn’t make it. “What stopped you”, I asked. He looked surprised. “You did”, he said, “I could quote every word you ever said about cannabis, and all of it came true.”. He also managed to stop some of his friends. He got a first for his dissertation, spent a year with a friend of mine, a toxicologist as a technician, did an MSc in neurology, and is now researching brain diseases towards a PhD.

Because CB1 receptors are in the motor area of the cortex, psychomotor performance and muscle control are affected. People should not drive. Airline pilots, on flight simulators could not land their planes properly even up to and beyond twenty-four hours after a joint and had no idea that anything was amiss. If you have a joint today, you should not be driving tomorrow. Cannabis has been implicated in more vehicle accidents in some American surveys than alcohol, although ten times as many people drink. One ‘spliff’ is thought by some experts to have the same effect as the amount of alcohol needed to just exceed the drink-drive limit.

THC, by dissolving in the fatty cell membranes, expands them, it is a partial anaesthetic, and so interferes with their structures and alters other receptor sites. The transmission of other neurotransmitters is therefore disrupted. It is a multi-faceted drug.

CB2 receptors are found in the cells of our immune system and THC disrupts the copying of DNA into new cells being made in the body. Fewer white blood cells are produced and some are abnormal. As a result, people are more likely to fall ill, their sickness will be prolonged and more severe. AIDS patients, with an already weakened immune system would be well advised to steer clear of this drug.

The heart also contains CB2 receptors. The heart rate is increased and blood pressure rises. A report from an Athens hospital in 2000, found three young men, heavy cannabis users, average age twenty-five, with heart attacks that could not be explained away except by their use of cannabis. A report in 2002 found that middle-aged people were 5 times more likely to have a heart attack in the hour following the smoking of a joint.

Cannabis smoke contains more of some of the carcinogens found in tobacco smoke and deposits three to four times as much tar in the airways. Even 20 years ago, lung biopsies of young French and American soldiers were finding pre cancerous cells, not usually found till middle age in tobacco users. As well as lung cancers, rare head and neck cancers are now being seen in young cannabis users, not found in tobacco smokers till the average age of sixty-four.

Doctors in Sweden are advised to suspect cannabis use when young people present with bronchitis, the link is so common.

Cannabis smoke burns at a higher temperature, the smoke is inhaled deeper and held longer in the lungs. One joint in cancer terms is thought to be the equivalent of five cigarettes. The British Lung Foundation was planning recently to start warning young pot-smokers of these dangers by text messages. Collapsed lungs, lungs shot through with holes and young people needing transplants are all part of the sorry saga.

Sperm have very high concentrations of CB2 receptors, and the female uterus is rich in anandamides, so it is hardly surprising that cannabis can have significant effects on the reproductive process. THC also interferes with the production of the sex hormones.

Human sperm have consistently been seen to be lower in numbers, and with decreased mobility. Surveys on young male pot-smoking patients, twenty years ago in Kingston Hospital, Jamaica, found 20% complaining of impotence and 35% with a sperm count so low, it would render them sterile. And that was when the strength of cannabis was a tenth of what it is today.

A very recent report from Buffalo in The States, showed sperm of cannabis users were less likely to be able to fertilise eggs. The sperm were swimming too fast too soon and burning themselves out long before they could reach the eggs. It also confirmed the significantly reduced numbers of sperm and seminal fluid in cannabis smokers.

In the late seventies and early eighties, a rash of papers found various abnormalities and even stillbirths in the offspring of mice and rats exposed to cannabis. Some of this older research has been criticized for various reasons but in 1994, the eminent cannabis researcher, Australian Professor Wayne Hall said, ‘It would be unwise to exclude cannabis as a cause of malformations until larger studies incorporating better controls have been carried out’.

One thing that is consistent in the research of today and twenty years ago, is the reduction in weight and length of the baby, the equivalent of smoking ten to fifteen cigarettes a day. Low birth weight relates in later life to diabetes, heart disease and high blood pressure. These babies also had mild symptoms of withdrawal. Three studies in the nineties linked cannabis use to a ten-fold increase in cases of one form of leukaemia, and increases in two other forms of childhood cancer.

In December, 2002, one in every eight babies born in The Princess Royal Maternity Hospital in Glasgow, had been exposed to cannabis before birth. Seventy-five per cent of babies exposed to drugs in the womb have medical problems later in life compared to twenty-seven per cent who are not exposed.

Just as I was preparing this talk about a month ago, I met a woman whose daughter had become schizophrenic from cannabis use. She then became pregnant and had a baby at the age of seventeen. She begged her mother to take in the little boy as she could not look after him herself. Grandparents have very few rights so they had to fight through the courts which took most of their savings. The baby suffered from epilepsy for some time after it was born, her daughter will be on medication for life.

The progress of babies born to cannabis-using mothers is being followed in a long-running investigation in Ottawa by Peter Fried and others:

The parents reported above average problems with behaviour, decreased attention and more impulsiveness. Fried has also warned of the delayed maturing of the visual system.

Deficiences in neurological behaviour are not really apparent till the age of four. This is when children start using their ‘executive functions’ (the ability to plan things and solve problems). By the age of 12 these problems were still apparent. Fried also warns that today’s stronger varieties will almost certainly make things worse.

Other researchers have come up with supporting evidence. In two studies of three year-olds, one found the results of intelligence tests to be below normal, the other, investigating sleep patterns, found more problems, more arousals and low sleep efficiency.

I would like now, to address a few of the controversies surrounding cannabis.

The first is the medical argument.

In 1979, a pot-using American lawyer, Keith Stroup, said, “We will use the medical marijuana argument as a red herring to give pot a good name”. In the early nineties, Richie Cowan his successor at NORML, the National Organization for the Reform of the Marijuana Laws, echoed this by saying, “Medical marijuana is our strongest suit. It is our point of leverage which will move us toward the legalisation of marijuana for personal use. This campaign is still ongoing.

There may well be some ingredients in the cannabis plant that may prove beneficial in medicine. But that is the point — the ingredients. Medicines, by law, have to be pure single chemicals so that their actions are predictable and controllable. Heroin and cocaine fall into this category. THC is already available as Nabilone in Britain and Marinol in the USA. The pro-legalisers don’t tell you this — they want their joints. These prescription drugs however are unpopular with doctors because of their side effects. Currently the BMA is testing some of the other cannabinoids, there are around sixty of them in the plant, and no one should have a problem with this. It is estimated that people suffering from glaucoma would need six joints a day to maintain reduced pressure in the eyeball. Hardly useful members of the community. It’s like saying to someone, “take up smoking to get your weight down”. Nicotine suppresses the appetite. Any GP giving this advice would be severely censured.

In November 1996, Proposition 200 permitted physicians in Arizona to prescribe marijuana with no limitation on the age of the patient or the disorder involved. Two months later, in January, 1997, a poll revealed that 85% of the voters believed it should be changed, 60% wanted it repealed and 70% said it gave kids the impression that it was OK to smoke pot. In 1998, 109 distinguished scientists from all over the world, held a conference in New York on medical marijuana. In 1999 their conclusions, published in Marijuana and Medicine, stated, ‘Marijuana or THC do not qualify as safe or effective medications which aim at restoring or maintaining physiological functions of cells, organs and organisms .They have no place in a modern pharmacopoeia from which cannabis was eliminated in the first part of the century’.

A more recent ‘ploy’ of the pro-legalisers is the promotion of hemp. Hemp is cannabis. They claim its needed for everything from ropes to cloth and newsprint. In reality it’s twice the price of the finest linen, paper from trees is much cheaper and ropes rot, and are not so strong as the synthetic ones we use today. Why? — It is a very simple chemical process to extract the 0.25% THC from hemp, purify and concentrate it to a very powerful 40% which they call CHAW.

There is a strong movement for the legalization of cannabis. So who are these people?

Most are users, or their children are. Some, like Richard Branston, would make a lot of money selling it, Others are libertarians. “We can do what we like with our bodies, it’s no one else’s business”. That’s fine as long as it doesn’t affect or interfere with anyone else. But, stoned drivers can and do kill others. Addicts get treatment at taxpayers’ expense. Stoned workers are inefficient and unproductive, and yes, passive smoking does occur. And where’s the liberty in making yourself a slave to a toxic drug for life?

Another controversy is the gateway theory. “Does cannabis lead onto other drugs’ ? Well it can! Lots of surveys in America by Denise Kandel point to this being the case. Level of usage is closely correlated. She found that, of those using mar between 10 and 100 times in their lifetime, 51% went on to harder drugs. From 100 to 1,000, it rose to 79%, and over 1,000 times it was 90%. Studies more recently from Australia and New Zealand, always controlled for confounding factors, have found that weekly users are sixty times more likely to progress, and the trend is confirmed by research on twins.Of course not everyone will go down this route, but almost one hundred per cent of heroin users started on cannabis.

People often compare the cannabis situation today with prohibition in the 30’s. The comparison is false. An attempt was made then to make a drug that was legal, illegal A drug that was used by most of the population, could be used without damage to health and had been around for centuries.

Cannabis is currently illegal, and even when it was legal, was only used by a minority of individuals. Use over the centuries has always been patchy. Regular use of cannabis today is around 8 to 9%, not the 30 to 40% of people who have tried it. How many children try smoking? — 90%? We’re stuck with tobacco and alcohol, If introduced now, they would almost certainly be controlled drugs. We are desperately campaigning to stop people from smoking and abusing alcohol, do we really need another easily obtainable legal drug to add to the misery caused by the other two? Pulling the genie back in the bottle is not an easy task.

In fact, from a health point of view, prohibition was a spectacular success. Alcohol consumption declined, deaths from cirrhosis of the liver fell by one third, cases of alcohol-induced psychosis plummeted. Child neglect, juvenile delinquency and alcohol-related divorces all dropped by 50%.

Now I want to tell you, at least in my view, why we are in such a mess with drugs.

Parents must naturally assume that drug education in schools strongly discourages children from starting to use drugs. They could not be more wrong.

The vast majority of drug educators teach harm reduction and have done so for the past fifteen years or so, Harm reduction has its legitimate place when dealing with known users to try to limit the damage with the aim of getting them to stop. They can be encouraged to ‘chase the dragon’ inhale the fumes from heroin rather than inject it, and so avoid all the blood-borne diseases like AIDS and hepatitis. It has no place in the classroom where around 90% of pupils have no intention of following that way of life.

One of the favourite phrases of harm reductionists is “informed choice There should be no choice — drugs are illegal. Surely teachers of all people should be seen to be upholding the law. And anyway, they are currently not being informed properly, especially about cannabis, to make a choice, more on this later.

Harm reductionists don’t tackle” drugs, they accommodate them. Adults are opting out and abrogating their responsibilities. The first duty of parents, and indeed all adults, is the protection of vulnerable youngsters from anything that puts them in danger. We don’t let our offspring cross a busy road till they are old enough, or run towards a fire and burn themselves, why abandon them to drugs? Nor do we let them choose to break the law in other ways, e.g. speeding or petty pilfering.

It’s not surprising in this climate of acceptance, that drug use is rising, Preventing children from starting to use drugs is, after all not the aim of harm reduction, Children need rules and regulations. The only way they feel safe and secure is when they have boundaries to kick against. They often use their parents as an excuse when they want to opt out. “Dad would kill me”, is a phrase frequently overheard. They have no time for teachers who can’t control a class or try to be trendy. Often the boys who come back to see me after they have left are the ones I have had to discipline most severely.

I never say, “Don’t do drugs” or “just say no”. I simply point out, in biological terms, what can happen to their brains and bodies. I add to that all the social, family, emotional, educational and employment consequences of that way of life and they begin to appreciate its futility of it. Nor am I above a bit of emotional blackmail. I remind the boys that when they were pregnant, their mothers would have been fanatical about what they put into their bodies in case it harmed their unborn child. How devastating must it be for parents to have to sit back and watch their offspring ruining their brains and bodies with toxic chemicals.

Prevention does work. The most spectacular success of a prevention programme was seen in the United States between 1979 and 1991. This was the famous “Just say no” campaign. Don’t let anyone tell you it didn’t work. Parents got fed up with the trendy excuses for drug taking and collaborated with teachers, the police, social and youth workers, customs and excise and the children themselves, to foster the idea that drug-taking is not normal and was indeed harmful, and it worked ! The number of drug users fell from 23 to 14 million, a reduction of 60%, use of cannabis and cocaine halved, daily cannabis taking fell by 75%.

In surveys at the time, the most common reason for abstaining from, or quitting cannabis use was 70% with concerns over physical and psychological damage. Parental disapproval played a large part with a surprising 60%, as did the law, 40%. In 1991, they thought they had licked the problem and took their eyes off the ball. Inevitably usage once again rose, but now, under a new preventionist drug tsar, John Walters, once again it is on the decline.

The Swedes have always had excellent prevention programmes in place, and their whole culture is anti-drug. Sweden has a very low level of drug use.

Harm reduction literature consistently trivializes cannabis. Schools are bombarded with harm reduction literature, some of it is unbelievable and quite shocking. Here are some examples of the Manchester-based charity, Lifeline’s approach. Their leaflet on cannabis shows how a joint is rolled, The last line reads, “A lot of people who are now both parents and grandparents smoked cannabis during the sixties and seventies The first piece of advice they give to kids when their parents find out they are using drugs is ‘Don’t get caught in the first place”. Other street-wise pamphlets are full of graphic pictures of sex and four-letter words.

When I gave evidence to the Home Affairs Select Committee on cannabis, I showed them some of this stuff. They were, to give them their due, collectively shocked, and initiated an inquiry into their funding, which incidentally comes from central government and health authorities. The Sunday Telegraph at that time, took up the story. The latest catalogue had “self-funded” beside many of the pamphlets, so it would appear that something has been done, it would have been nice to have been told.

Drug scope, currently advising the government on all aspects of drugs, distribute a cannabis leaflet with two young men in a field of marijuana, on the policeman’s helmet of one it says, ‘Have fun, take care. They consistently deny that cannabis is physically addictive in spite of abundant scientific evidence to the contrary, and fail to mention some of its effects, while playing down the significance of others. They demand conclusive proof of the long-term effects. We don’t have conclusive proof that cigarettes cause lung cancer, but because of animal experiments and statistical correlations we accept the fact. Why is it different with cannabis? They don’t want anyone arrested for the possession of small quantities of drugs — any drugs! Needless to say, they are enthusiastically endorsing David Blunkett’s ill-advised proposal to down grade cannabis. On Radio 4 on the 27th May this year, Roger Howard, then Head of DrugScope, called for the reclassification of ecstasy and LSD as well as cannabis.

For a government that banned beef-on-the-bone with its infinitesimal risk of causing CJD, it is incomprehensible that they are contemplating a move that will inevitably result in more people using a substance proved to be harmful ‘We must err on the side of caution’, said a government spokesman at the time, Indeed we must, Have we learned nothing from the lawsuits brought by tobacco users?

Since David Blunkett’s ill-advised announcement to down grade cannabis, taking of the drug by 14 to 15 year olds has shot up 50%, from 19 to 29%.

Connexions, an organization now charged by the government to give advice to schools on such matters as careers, counselling and drugs, recently sent drug leaflets to my school, They were written in trendy ‘street-cred’ language by ‘The Clued-up Posse’ a group of kids from Kirkcaldy, Fife. The one on cannabis contained virtually no information on the dangers of pot, but masses on risk reduction. My sixth form thought it was patronizing, useless and positively encouraging of drug use. They also pointed out that it mimicked a Rizla packet. What sort of message does that send out? I made a fuss and The Sunday Telegraph, The Daily Mail and even The Sun took up the story. The leaflet has now been withdrawn.
Talking of messages, this is a worksheet from a book specially written for PHSE in schools. No comment!

Then we have all the blatant promotion of cannabis with logos on T-shirts, jackets and bags and on the front of magazines like Ministry. We have pop-stars and even MPs openly boasting about using cannabis, and songs that glorify drugs. Pro-legalisation articles vastly outnumber those against in the national press, and information about where to get cannabis seeds and paraphernalia is freely available in magazines and on the web. Propaganda like this makes my job a never-ending uphill struggle.

Drugs are illegal because they are dangerous, not dangerous because they are illegal.

The war on drugs has not failed. It has yet to be fought. And it must start with children. Remove the demand and you remove the problem.

I want to finish with two quotes.

Dr Robert Dupont, founder of the National Institute for Drug Abuse in The United States said, ‘I have been apologizing to the American people for the last ten years for promoting the decriminalization of cannabis, I made a mistake. Marijuana combines the worst effects of alcohol and tobacco and has other ill-effects that neither of these two have”.

He also said, ‘In all of history, no young people have ever taken marijuana regularly on a mass scale. Therefore our youngsters are in effect making themselves guinea pigs in a tragic experiment. Thus far our research clearly suggests we will see horrendous results’.

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