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Lord Winston: My Lords, before my noble friend sits down, perhaps I may put one question. First, is he aware that it is possible to administer drugs nasally or by rectal suppository? Secondly, does he agree that if he reads the evidence that is set out carefully in the report one of the matters constantly referred to by many of the people who currently use cannabis illegally is that they try to avoid becoming intoxicated by the drug if at all possible? They want pain relief but do not want the "high" about which my noble friend complains. Perhaps my noble friend would like to address that issue briefly.
Lord Mackenzie of Framwellgate: My Lords, I am grateful that my noble friend raises that point. I am aware that there are other means of administering the drug. My point is that the prescription system will be abused. Unfortunately, doctors, policemen and many other people in society break the rules. In response to my noble friend, perhaps I may quote the words of the British Medical Association:
Lord Butterfield: My Lords, I rise in the lull after that devastating bowling attack on our wicket, but I believe we shall shortly be able, with the passage of time, to recover ground and come back into the game. Perhaps the next speech will achieve that.
I wanted to say first of all, like the others, how much I enjoyed sitting on the Committee with my old friend Lord Perry of Walton. He used to play cricket for me: perhaps that is why I am speaking of great bowling efforts from the last speaker. We used to play cricket together for the Medical Research Council and do our best to defend our reputations and our castles in that way. May I just say also that we were immensely lucky in our Clerk? He had a very clear mind and I do not think anyone could fault the logic of the way he presented the material and the boxes he constructed in the report. In Professor Leslie Iverson, an expert witness, we were very fortunate to have someone who is at the absolute forefront of modern cannabis pharmacological research.
However, as a young group of physiological Army research workers, we were really much more interested intellectually, looking back I now realise, in the effects of the other end of the intensity of the radiant heat story. We became very interested in the pain you can get from radiant heat. You may well, for example, lie for some time in the sunshine in your garden and suddenly be woken up by the sharp focus of light on your leg by one of your naughtier children.
When we were looking at this one of the very first things we realised we had to find out was how big an area of the skin of our volunteers--not policemen but soldiers--should we irradiate to see what were the threshold doses of radiant heat which could produce the effects we might be interested in. This, I now realise, led us to a most interesting situation because we found that if you irradiated an aperture of say 3cm in diameter you got a threshold for pain--you felt it and it hurt--but if you reduced the size of the aperture you could give more heat before you got the painful sensation; and if you reduced it even more you could give even greater amounts.
The only report we could write for the scientific advice of the Army Council--we did not use it very much--was one that we called Studies and Observations in the Royal Army Medical Corps on the Central Summation of Pain. As you can imagine, the authorities wanted to know what on earth that had got to do with the atomic bomb. I now realise in retrospect that this central summation of pain could be a very quick way of looking for an effect from the cannabinoids; I am not going to say smoking marijuana or THC and other products which we could take as a tincture, I suppose, or whatever. In this way we might perhaps be able to come up with a quick piece of evidence that this compound, which is reputedly graced with all kinds of important qualities, indeed has some.
I am pleased to realise that there are people such as Professor Wall at the United Medical and Dental Schools of St. Thomas' and Guy's Hospitals, who is a big worker in the field of pain. While I am not up to date with the names, I wish to have these in the record because people in the research world do not receive their just deserts. There is a lady at Hammersmith called Dr. Holdcroft. Dr. Stewart of Dundee has worked on phantom pain in limbs. There is a Dr. Lambert at Leicester; and Professor Notcutt is very interested in these problems. I wish to have their names in the record
By doing some physiological experiments on pain we may be able to find out whether the cannabis cannabinoids could have an effect on pain. If so, it will give a great thrust to bringing a reasonable proposition to the Government for ongoing research.
I noted the words in the report about there being a certain stigma about research into cannabis. It is most unfortunate. Before too long, I hope that we shall without too much stigma be able to take Professor Mackenzie along with us in the search for suitable preparations. Perhaps patches, pills, or inhalations such as I take for my asthma may bring necessary relief on to the sites--the nerves--for those people who have these painful and worrying conditions.
I feel guilty if I obstruct relief for pain for people towards the end of their years. We have to be careful about cannabis when dealing with young people. However, I think that older folk can take bigger risks with the effects of the compounds. I thank noble Lords for listening to me.
Lord Walton of Detchant: My Lords, it was a particular pleasure to have served on the sub-committee which produced the report for your Lordships' Select Committee on Science and Technology which we are now debating. Like other noble Lords, I wish to pay a warm tribute to the outstanding leadership and chairmanship of the noble Lord, Lord Perry of Walton, whose judicious handling of the evidence and whose guidance was outstanding throughout, as indeed was the advice given to the sub-committee based upon his encyclopaedic scientific knowledge and experience by its adviser, Professor Leslie Iversen. As others have said, we must not overlook the exceptional drafting skills of our clerk, Mr. Andrew Makower, with whom I have had the privilege of working several times in the past. His command of the English language, his ability to interpret evidence and comprehend and analyse complex scientific arguments have been impeccable.
Let me say, first, as others have done, that we were in no doubt that cannabis should continue to be a controlled drug, since, although it is not highly addictive, it can lead to psychological dependence; and in some dependent individuals regular heavy use can produce a state of near-continuous intoxication making normal life impossible. In addition, it is sufficiently intoxicating so as to impair the ability to carry out critical tasks such as flying, driving or operating machinery. That effect lasts for several hours, and possibly for much longer after taking it.
My especial concern relates to the evidence that the drug impairs cognitive function during its use and may indeed, in heavy dosage, produce long-term cognitive decline. From my long experience as a neurologist, I can also confirm that it can clearly exacerbate pre-existing mental illness. Indeed, in heavy dosage, it can produce a delusional psychosis with hallucinations which can lead to a mistaken diagnosis of schizophrenia.
Many years ago I met a bright medical student from overseas in whom such a psychosis developed due to heavy cannabis consumption of which his doctor and family were totally unaware. Schizophrenia was diagnosed. He was treated with powerful neuroleptic drugs and developed severe and irreversible side effects which made it impossible for him to continue what had seemed likely to become a promising career in medicine.
Those who argue that cannabis may be no more dangerous in the long term than tobacco, for example, must recognise that if tobacco were now to be introduced into UK society for the first time, it is my view that because of its appallingly harmful effects, it too would now be a controlled drug.
Those facts indicate clearly that recreational use of cannabis must continue to be illegal. Its effect of lowering blood pressure, a particular risk in individuals with cardiovascular conditions, is another important factor.
If, then, the drug has such important and troublesome side effects, why did our sub-committee recommend that it be moved from Schedule 1 to Schedule 2 under the Misuse of Drugs Act, allowing its prescription by doctors for named patients only? Why did we suggest that, since the synthetic cannabinoid analogue nabilone is licensed for use under Schedule 2 while dronabinol, pure THC, although not yet licensed in the UK, is also in Schedule 2 and could be prescribed for named patients?
I must reluctantly admit, having been a fervent supporter throughout my professional life of the controlled clinical trial, and having organised and conducted several such trials in the treatment of neurological disorders, that there is logic in the suggestion that it might be better to await the outcome of the trials now being planned by the Royal Pharmaceutical Society with the collaboration of GW Pharmaceuticals.
Many scientists and doctors, whose opinion and professional expertise I respect, such as Sir William Asscher, who will be supervising those trials, have argued that the sub-committee should have awaited the completion of those studies and that the Government should delay moving cannabis from Schedule 1 to Schedule 2 until the results have been analysed.
Why then did the sub-committee appear to fly in the face of informed pharmaceutical and clinical opinion by making the recommendations that we did? Our reasons were fourfold. First, there is increasing evidence that cannabis and particularly its constituent cannabinoids have some predictable effects upon the central nervous system where, through their action upon cannabinoid receptors, they may potentiate, as the noble Lord, Lord Perry, said, the effects of analgesics. In consequence, in patients with terminal cancer, the doses of drugs such as morphia or heroin required for pain relief may be less if cannabis can also be given. There would then be a consequent reduction in side effects.
Thirdly, while I must accept that virtually all the clinical evidence presented to us in the course of our inquiry was anecdotal, nevertheless, we found it convincing. Therefore, we think it likely, although by no means certain, that cannabis may be an effective remedy for the painful spasms of MS and that it may also have a significant potentiating analgesic effect as well as offering effective control of the nausea and vomiting which may complicate AIDS and chemotherapy for advanced cancer.
The fourth reason underlying our recommendations was not based solely upon compassion for those suffering from the disorders to which I referred who have found the illegal consumption of cannabis beneficial. But we heard much evidence--yet again anecdotal--strongly suggesting that natural cannabis, however administered (usually at present through smoking), had proved effective when the synthetic tetrahydrocannabinol analogue, nabilone, had not. And for this reason we did not regard it as being fair or reasonable to wait five years for major trials to be completed before making cannabis available.
I understand fully the strictures included in recent statements by officers of the BMA and by Sir William Asscher; they stressed that herbal cannabis, containing a mixture of more than 60 cannabinoids, is not yet available as a pure preparation. In their view natural cannabis, however administered, could have unacceptable toxic effects. In response I can but say that the evidence which we received--for example, on behalf of patients with multiple sclerosis--was, first, that the level of dosage of herbal cannabis required to relieve their symptoms produced relatively few psychoactive effects; and, secondly, that the amount required was not such as to carry a risk of producing the major toxic effects which high doses of cannabis are known to cause.
We were much encouraged in our view by the knowledge that Dr. Geoffrey Guy of GW Pharmaceuticals has obtained a Home Office licence to cultivate natural cannabis with the intention of producing a purified herbal preparation which, it is hoped, will produce consistent or at least reasonably consistent blood levels of THC when specific doses are administered. Proof that this will be feasible will take some little time to achieve; but in the meantime, in the interests of the patients with the conditions I have mentioned, I am now persuaded--against my original
Another powerful reason for suggesting that such a herbal preparation should be made available under Schedule 2 was based on evidence we received that, because of the presumed beneficial effect of natural cannabis, as others have said, some doctors have apparently connived at its illegal use. Whenever evidence of such behaviour on the part of doctors and patients has been brought formally to the attention of the law, the individuals have usually been treated leniently. In other words, much of society seems now to be condoning illegal use specifically for medical purposes; it was our conclusion that that position should now be regularised without waiting for the results of lengthy clinical trials.
The question then arises as to how such a natural preparation should be administered. Here it is clear, as our report confirms, that much research is needed as smoking of cannabis could be tolerated only in the very short term since smoked cannabis carries just as much risk of causing cancer of the respiratory tract as does tobacco smoking; indeed, as Professor Ashton said, it may be even more harmful. Hence any natural preparation made available for prescription must be tested in alternative formulations. Inhalation of an aerosolised extract is the method most favoured but sublingual administration or administration by a pessary or a suppository must not be overlooked. Each of those techniques should produce more effective blood levels of cannabinoids than would ingestion, in view of the inevitable delay resulting from absorption through the gastro-intestinal tract with metabolism in the liver.
Of course, the question will inevitably be raised, as it was raised by the noble Lord, Lord Mackenzie of Framwellgate, as to whether legalisation for medical purposes might be regarded as a stalking-horse for legalising recreational use. I am satisfied, as our report makes clear, that we must reject that suggestion. Similarly, we are well aware that even in the most carefully regulated societies there will always be a possibility that a prescribed drug will be diverted to illegal use as has sometimes happened with morphia, heroin and their analogues. That is a matter of which, as a former president of the General Medical Council, I am only too well aware. But I believe that the professional regulatory authorities are fully aware of that potential problem and would be expected to deal just as harshly with those involved in diverting prescribed cannabis to improper use as they already are in relation to the diversion of heroin, for example.
Like many other members of the sub-committee, I was dismayed by the immediate knee-jerk reactions of the Government and the BMA to our report at a time when surely neither could have read it fully so as to comprehend the cogent reasons underlying our proposals. So compelling, I believe, is the anecdotal evidence which we heard, and to which we have referred in depth, that I firmly adhere to our recommendations.
I urge the Government now to consult the Advisory Council on the Misuse of Drugs and to delay their formal response to our report until after they have received and considered the advice of that council. We trust that that body will agree with our conclusion that an appropriate preparation of herbal cannabis should be transferred to Schedule 2 under the regulations and that the Government should raise the matter of rescheduling the remaining cannabinoids as they become available, with WHO in due course in order to facilitate research into their use.
All who served on the sub-committee were well aware that, in making the recommendations that we did, we were in a sense flouting conventional medical and scientific practice. At the risk of undue repetition, I can only say that we would not have done so were it not for the volume of written and oral evidence presented to us, relating to the experiences of individual patients, but also to current scientific knowledge. We are convinced that it is important for the well-being of many individuals that limited amounts of natural cannabis should soon be made available for prescription by doctors to named patients only. I trust that the Government and those professional bodies in medicine which have commented adversely upon our report, in striking contrast to the almost universal support that it has received in the public media, will now think again.
Lord Rea: My Lords, like other noble Lords, I should like to say, first, what a privilege it was to be yet again co-opted on to the sub-committee and to serve under our excellent and learned chairman and specialist adviser. I say "learned" in this case in the scientific sense. Of course, I shall not neglect to mention the work of our excellent Clerk and his team.
Apart from our report and recommendations, with which I fully agree, I should like to point out that the volume containing the evidence presented to the committee is, as pointed out by the noble Lord, Lord Perry, a fascinating and valuable read in itself. It is extremely cogent and quite difficult to put down, as some of its pages are so fascinating. It will prove to be a most valuable source document in the future for anyone interested in the case for or the case against making cannabis legal and more accessible, whether this be for medical or so-called "recreational" purposes. It is also an accessible and well-referenced account of the whole subject.
Like the noble Lord, Lord Walton, I should like to mention that we looked at the adverse effects of the drug in great detail, as well as looking at its possible medical benefits. Those adverse effects are summarised in paragraph 8.19 of the report. Our final recommendation, which the noble Lord, Lord Walton, iterated--and I shall repeat--is that,
The committee was surprised, at least I was, that there were no deaths--I repeat, no deaths--directly attributable to cannabis toxicity either from acute overdose or prolonged use in the years 1993 to 1995. That is certainly not the case with many medicines which are obtainable over the counter. My noble friend Lord Winston mentioned paracetamol and aspirin, suicides from which we heard about during Question Time about two weeks ago on (I think) 18th November. So cannabis really does seem to be safer from the point of view of its lethal consequences than aspirin. Indeed, this very safety was a major factor in our recommendation that it should be moved from schedule 1 to Schedule 2. But because of its psychotropic power and possible long-term neurological effects, which have been described so well by the noble Lord, Lord Walton, it was felt that it should remain a controlled drug.
I would like to add a personal view here. If the possession of cannabis were ever to be decriminalised or legalised--which some may say is a sensible policy, but that is well outside our committee's remit--its supply should still be controlled and monitored carefully. This would be much easier if it was classified as a controlled substance, only available from licensed sources.
As I have said, the committee's remit did not include consideration of the "recreational" use of cannabis, yet our deliberations and recommendations always had to bear in mind the sort of criticisms that the noble Lord, Lord Mackenzie, has brought forward--that our recommendations might be misinterpreted as being the "thin end of the wedge", a "stalking horse" or, as he said, a "Trojan horse", leading to the medical prescription of cannabis for its psychotropic effects.
There is little or no problem when discussing the prescription of purified cannabinoids since they are not, as far as I know, ever sought by recreational users. But cannabis itself may seem, on the face of it, to be more problematic. This is not necessarily so. As other noble Lords have pointed out, heroin is a prescribable drug, being a schedule 2 preparation, but there is no evidence that it is now being prescribed by doctors in any more than a small number of cases for other than genuine medical reasons. Until the early 1970s it could be prescribed by general practitioners, in the National Health Service or privately, for the treatment of heroin addiction. For the past 15 years that has not been allowed and it has been available only in specialised drug clinics. Whether that is the right policy is arguable, but there is no reason why the same prescribing restrictions should not apply to cannabis, which is not as highly addictive as heroin in any case.
The committee is aware that, despite the considerable anecdotal evidence that was presented to it--and also described in the BMA's report of 1998--the scientific evidence for the effectiveness of cannabis to alleviate the symptoms of a number of conditions is still inadequate and further research is urgently needed. All noble Lords who have spoken have said that. The Government's opinion, however, is that this further research needs to be completed before they can consider altering the present status of cannabis. As many noble Lords have pointed out, that was the knee-jerk reaction of the Home Office.
May I make an aside at this point and ask why it is that the Home Office has the last word on this. When we are considering the therapeutic benefits of a possibly extremely valuable drug, the Home Office should at least consult with the Department of Health before making off-the-cuff statements like this.
However, the Home Office is to be congratulated on its relatively speedy granting of licences for the two important studies by Dr. Guy and the Royal Pharmaceutical Society. But, as many noble Lords have said, it will take at least five years before these trials are completed and fully assessed. Meanwhile, a number of patients--particularly those with multiple sclerosis--have found that cannabis leaf or resin is the only substance or medicine that gives them relief. They will continue to have to break the law while obtaining supplies of variable strength from irregular and illegal sources.
It is interesting to see how the committee, which included such distinguished scientists, reacted to the anecdotal evidence which was presented to it, both personally by actual sufferers and by doctors who described the experience of their patients. I can best illustrate the compelling nature of this evidence by quoting a little from a few cases. Perhaps I may start with a more lighthearted one. Dr. Robson, director of the drug dependence unit at the Warneford Hospital, Oxford, related the following anecdote. He said:
Someone who had a much more severe problem was Clare Hodges, Director of the Alliance for Cannabis Therapeutics. The gist of some of her testimony has already been quoted. She has had multiple sclerosis for 15 years, with spasticity, nausea, poor appetite and great discomfort in her bladder. For some nine years she
Many more examples were given to us. An interesting case was described by Dr. Fred Schon, a consultant neurologist and neuropharmacologist. His patient had a rare eye complication of multiple sclerosis called pendular nystagmus which was resistant to all standard treatments including nabilone. The patient reported a dramatic benefit from smoking cannabis which he said completely abolished his symptoms. In trying to replicate this with cannabis oil capsules, which was the only preparation Dr. Schon was allowed to prescribe by the Home Office, he obtained no benefit. He was unable to get a licence to study the beneficial effects of the smoked product.
When full chemical and pharmaceutical attention is focused on cannabis it may be possible to isolate the most effective cannabinoids in the most effective combination and to administer them by a less crude method than smoking and inhaling this semi-combusted product of cannabis leaf or resin. However, it appears that a significant number of patients with various degrees of neurological damage get remarkable relief from their unpleasant symptoms by inhaling that particular concoction of cannabinoids.
I share the belief of Dr. Robson, as I think do the other members of the committee, that compassionate reefers, despite the adverse effects of smoking itself, are fully justified if a patient has severe symptoms and is suffering from an illness, such as cancer or AIDS, which may shorten life in any case. But I would go further and suggest that these reefers or other preparations of smoked cannabis should be available on prescription on a named basis to patients with less immediately life threatening conditions. Of those, sufferers from multiple sclerosis will be much the most numerous.
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