Select Committee on Science and Technology Written Evidence


Memorandum from the Advisory Council on the Misuse of Drugs (ACMD)


  1.1  The Advisory Council on the Misuse of Drugs (the Council) was established, as a non-departmental public body, by the Misuse of Drugs Act 1971 (the Act). Its current membership is shown in Annex A.

  1.2  The Council's terms of reference are set out in the Act as follows:

  "It shall be the duty of the Advisory Council to keep under review the situation in the United Kingdom with respect to drugs which are being or appear to them likely to be misused and of which the misuse is having or appears to them capable of having harmful effects sufficient to constitute a social problem, and to give to any one or more of the Ministers, where either Council consider it expedient to do so or they are consulted by the Minister or Ministers in question, advice on measures (whether or not involving alteration of the law) which in the opinion of the Council ought to be taken for preventing the misuse of such drugs or dealing with social problems connected with their misuse, and in particular on measures which in the opinion of the Council, ought to be taken.

    (a)    for restricting the availability of such drugs or supervising the arrangements for their supply;

    (b)    for enabling persons afffected by the misuse of such drugs to obain proper advice, and for securing the provision of proper facilities and services for the treatment, rehabilitation and aftercare of such persons;

    (c)    for promoting co-operation between the various professional and community services which in the opinion of the Council have a part to play in dealing with social problems connected with the misuse of drugs;

    (d)    for educating the public (and in particular the young) in the dangers of misusing such drugs and for giving publicity to those dangers; and

    (e)    for promoting research into, or otherwise obtaining information about, any matter which in the opinion of the Council is of relevance for the purpose of preventing the misuse of such drugs or dealing with any social problem connected with their misuse."

  1.3  A further duty is placed on the Council in the Act to consider any matter relating to drug dependence, or the misuse of drugs, which may be referred to it by anyone of the Secretaries of State (as defined in the Act). The Home Secretary is, moreover, obliged to consult the Advisory Council before making any amendment to the Regulations to the Misuse of Drugs Act 1971.

  1.4  The Council ordinarily meets, in full session, twice each year but it has powers to meet more frequently if necessary. Much of the detailed work of the Council is carried out by its Technical Committee and its Prevention Working Group. Ad hoc working groups, with limited life-spans, are also established from time to time to undertake detailed examinations of specific issues. Over the past 18 months, for example, the Council has had a specific working party to examine the implications of the reports of the Shipman Inquiry. The committees and working groups report to the Council since that is the body responsible for formally advising the Home Secretary.


  2.1  The Council fulfills its responsibilities in various ways:

  2.1.1  The Council advises on whether substances should be controlled under the Act and, if so, into which Class and Schedule they should most appropriately be placed. The initial scrutiny of the available evidence is normally undertaken by the Technical Committee. The Technical Committee's membership is drawn from Council as well as others—co-opted members—with particular expertise. The Technical Committee's members are appointed by the Council, and the Committee reports to Council. Membership of the Technical Committee is shown at Annex B.

  2.1.2  The Council advises on arrangements for the safe custody, prescribing and disposal of medicinal substances controlled under the Act.

  2.1.3  The Council reviews arrangements for reducing the harmful effects of controlled drugs amongst those who continue to use them; and advises on appropriate harm reduction measures.

  2.1.4  The Council undertakes major reviews, through its Prevention Working Group, of problem areas relating to substance misuse. While much of this work relates to harm reduction (secondary and tertiary prevention), it also encompasses primary prevention. Its latest Inquiry report was Hidden Harm: Responding to the needs of children of problem drug users.

  2.1.5  The Council published its Reports, in previous years exclusively in hard copy and more recently, on its webpages at Since 1977, the Council has published 27 reports.


  3.1  Substances controlled under the Act are placed, on the basis of their harmfulness to individuals and society, into one of three classes:

        Class A (most harmful) includes cocaine, diamorphine (Heroin), 3,4-methylenedioxyme- thamphetamine (Ecstasy) and lysergic acid diethylamide (LSD).

        Class B (an intermediate category) includes amphetamines, barbiturates and codeine.

        Class C (less harmful) includes cannabis, benzodiazepines, anabolic steroids and gamma-hydroxy butyrate.

  3.2  This system of classification of drugs, under the Act, is related to determining the penalties for their possession and supply. The current maximum penalties are as follows:

        Class A drugs: For possession—seven years imprisonment and/or a fine; for supply—life imprisonment and/or fine.

        Class B drugs: For possession—five years imprisonment and/or a fine; for supply—14 years imprisonment and/or fine.

        Class C drugs:  For possession—two years imprisonment and/or a fine; for supply—14 years imprisonment and/or fine.

  3.3  The Misuse of Drugs Regulations 2001 (Statutory Instrument 2001/3998) defines the categories of people authorised to supply and possess drugs controlled under the Act. In these Regulations, drugs are categorised under five schedules:

        Schedule 1 includes substances such as lysergic acid diethylamide and cannabis that are not available for medical purposes. Possession and supply are prohibited without specific Home Office approval.

        Schedule 2 includes prescription drugs such as morphine and diamorphine that, because of their harmfulness, are subject to special requirements relating to their safe custody, prescription, and the need to maintain registers relating to their acquisition and use.

        Schedule 3 includes barbiturates and are subject to special prescription, though not safe custody, requirements.

        Schedule 4 includes benzodiazepines and are subject to neither special prescribing arrangements, nor to safe custody requirements.

        Schedule 5 includes preparations that, because of their low strength, are exempt from most of the controlled drug requirements.


  4.1  The Council and its Technical Committee consider evidence, from a variety of sources, about substances that are—or might potentially be—controlled under the Act. Sources of intelligence include information from:

    —  formal surveys undertaken for, or on behalf of, Government including the British Crime Survey, the Forensic Science Service statistics, general population surveys, school surveys as well as international/European surveys such as European School Survey Project on Alcohol and other drugs (ESPAD);

    —  the law enforcement agencies;

    —  voluntary sector organisations with concerns and responsibilities, for those who misuse drugs;

    —  professional bodies;

    —  published and unpublished scientific literature; and

    —  submissions from special interest groups and the general public.

  4.2  Substances considered by the Council and its Technical Committee over the past three years include:

    —  amineptine;

    —  benzodiazepines (as a class);

    —  buprenorphine;

    —  cannabis;

    —  gamma-hydroxybutyrate;

    —  gamma-butyrolactone;

    —  ketamine;

    —  khat;

    —  magic mushrooms;

    —  methylamphetamine;

    —  methylphenidate; and

    —  midazolam.

  4.3  When considering whether a substance should be brought under the scope of the Act (ie be designated as a controlled drug) the Council's advice is based on three domains of harmfulness:

    —  Physical and mental health;

    —  Dependence-producing potential; and

    —  Societal.

  4.3.1  Consideration of the harmfulness of a substance to physical and mental health covers three areas. The acute harmfulness of a substance refers to its propensity to produce harm during the hours (or sometimes days) after administration. Examples include respiratory arrest after excessive doses of barbiturates, or acute psychosis with amphetamine. Chronic harms are those which persist after short-term exposure or which develop as a consequence of repeated use. Cannabis-induced relapse, in individuals with schizophrenia, is an example of the former; whilst the carcinogenic effect of anabolic steroids is a feature of the latter. Substances that are given by intravenous injection pose special hazards because of needle-sharing by consumers. This is particularly the case for the transmisssion of blood borne infections (such human immunodeficiency virus and hepatitis C virus).

  4.3.2  Drug dependence is a complex phenomenon whose nature differs from substance to substance. It is related to the duration and amount used, as well as to characteristics of the user. It is also related to the pleasure that use of the substance gives. Dependence is generally associated with an increasing reliance on the drug, with psychological craving when consumption is reduced or stopped, and sometimes (though not invariably) with the development of physical withdrawal symptoms.

  4.3.3  Social harms include the potential damage to others when individuals are under the influence of the substance; other adverse consequences such as acquisitive crime to finance continued access to the substance. Costs falling on the National Health Service, to treat the consequences of the physical and psychological harms (including dependence), are also considered.

  4.4  Much of the evidence about a substance's physical and psychological harmfulness can be found in the relevant chemical, pharmacological, clinical and epidemiological literature. In assessing harmfulness the Council generally undertakes, or commissions, a review of the published and (wherever possible) unpublished literature. Valuable information can also be obtained from information about seizures made by law enforcement officers.

  4.4.1  The pharmacological, clinical and epidemiological literature is of particular value in assessing the physical harmfulness of a substance.

  4.4.2  Reliable evidence about the dependence-producing potential of a substance can sometimes be obtained from these same sources; but there can be serious omissions. The prevalence of dependency on individual controlled substances in the UK, for example, has been notoriously difficult to establish.

  4.4.3  Evidence about social harms is often the weakest data-set because of the inherent problems in gathering relevant information. In particular, evidence about the quality and potency of material used by consumers, their pattern of consumption, and the social consequences of their use, are all too often absent. In some instances the Council has commissioned primary research into areas of particular significance. In other cases the Council has had to relay on anecdotal evidence provided by individual Council members or others with expertise in the particular field. The Council does, however, gain invaluable information form studies carried out by organisations such as the British Crime Survey, the Forensic Science Service, and the National Criminal Intelligence Service.

  4.5  As with other national advisory bodies, the Council ultimately has to make informed judgements based on the available evidence and the collective experience and expertise of its members.

  4.6  The Council's advice to ministers is conveyed as either:

    —  a formal report with a covering letter from the chairman;

    —  a letter from the chairman; or

    —  a submission to ministers, from the Council's secretary.

  In some instances, the Council's chairman may request a meeting with ministers, or ministers may request a meeting with the chairman, to discuss the Council's advice. During the tenure of office of the current chairman of the Council (ie since 1998), no request for a meeting with ministers has been declined.

  4.7  On occasions, meetings are also held between the Chairman and the Director of the Home Office Drugs Strategy.


  5.1  We understand that the Committee seeks information about the Council's consideration of cocaine, cannabis, magic mushrooms and amphetamines. As indicated in paragraph 4.2, the Council has not discussed cocaine but has advised on the other three substances.


  5.2  Cannabis produces its effects on the brain through interactions between most active psychoactive ingredient, 9-tetrahydrocannabinol (THC), and specific proteins on the surface of cells known as cannabinoid receptors. Other psychoactive components in cannabis preparations, especially cannabidiol, interact with other receptors in the brain.

  5.3  Cannabis products were categorised as class B substances in 1971 (apart from cannabis oil, which was classified in Class A). Athough reviewed periodically, between 1971 and 2002, no change in legal status was made.

  5.4  The Council was asked to advise on the appropriate classification of cannabis, in October 2001, by the then Home Secretary (Rt Hon David Blunkett MP). The Council presented its report—The classification of cannabis under the Misuse of Drugs Act 1971—(available at, in March 2002, and advised that all cannabis products should be reclassified as class C. The necessary legislative changes came into force in January 2004.

  5.5  The current Home Secretary asked the Council, in March 2005, to review the classification of cannabis in the light of recent evidence about its possible adverse effects on mental health. He also asked the Council to advise on the extent to which the potency of cannabis products, as used by consumers, had increased over the past few years. The chronology of the development of the Council's consideration of this issue is in Annex C; and the Council's final report—Further consideration of the classification of cannabis under the Misuse of Drugs Act 1971— which was sent to the Home Secretary in December 2005, can be found at

  5.6  The Home Secretary announced his decision to accept the Council's recommendations, in full, on 19 January 2006. The Council's report was published on the same day.


  5.7  Amphetamine and its derivatives are known, pharmacologically as the phenylethylamines. The phenylethylamines include:

    —  amphetamine;

    —  methylamphetamine (metamphetamine);

    —  methylphenidate;

    —  phentermine; and

    —  fenfluramine.

  5.7.1  The substituted amphetamines include:

    —  methylenedioxyamphetamine (MDA); and

    —  3,4-methylenedioxymethamphetamine (MDMA, Ecstasy).

  5.8  Whilst the phenylethylamines have common pharmacological properties, there also are differences in both their qualitative and quantitative effects. These may be due to (apparently) small changes in their chemical structure or their chemical form (eg as base or salt). The phenylethylamines also exist as optical isomers which, despite their chemical similarities, differ in their pharmacological actions and potencies.

  5.9  Amphetamines and subsituted amphetamines are controlled under Misuse of Drugs Act 1971. Amphetamine and methylamphetamine are class B substances. The substituted amphetamines (MDA and MDMA) are class A substances.

  5.10  Following a visit to the US, in late 2003, the Permanent Secretary for Crime, Policing, Counter-Terrorism and Delivery at the Home Offfice asked the Council to undertake a detailed assessment of the harms posed by methylamphetamine; and to recommend measures that might need to be taken to prevent its misuse in the UK. Although there was at that time little evidence of such misuse in Britain, the Permanent Secretary was concerned that the widespread problems associated with its misuse in the US might spread to the UK.

  5.11  The details of the preparation of the Council's report on methylamphetamine are described in Annex D; and the report itself can be found at

Magic mushrooms

  5.12  Magic mushrooms contain, as naturally-occuring substances, psilocin and psilocybin. These compounds, like lysergic acid diethylamide, have hallucinogenic properties and are particularly harmful to those with mental illnesses.

  5.13  Under the Act products containing psilocin or an ester of psilocin are controlled as class A substances. However, the wording of the legislation (as well as its legal interpretaion in the Courts) suggested that magic mushrooms were only controlled (under the provisions of the Act if supplied in the form of a product. This included those that had been dried, or treated, prior to sale but excluded magic mushrooms sold as "fresh".

  5.14  In March 2004 the Technical Committee heard that, over recent years, there had been a substantial increase in the number of retail outlets selling "fresh" magic mushrooms. In fact HM Customs and Excise estimated the importation of 8,000-16,000 kgs during 2004.

  5.15  In December 2004, the ACMD received a letter from the Home Office notifying them of the Government's intention to initiate a change in the law that would clarify the legal position regarding magic mushrooms. The letter sought feedback from the ACMD, which was generally supportive and the Council agreed that clarification of the law would be helpful.

  5.16  The Government introduced this change in law by way of the Drugs Act 2005. Associated regulations were required to exclude some individuals from the offences under the Misuse of Drugs Act 1971. In May 2005 the Council endorsed a draft Regulation that would provide these exemptions in the law. The Council's opinion was communicated to officials in the Home Office, in a letter from the chairman, in June 2005. The Regulation came into force in July 2005.

January 2006

Annex A


Professor Sir Michael Rawlins (chairman)

Chairman, National Institute of Health and Clinical Excellence and Professor of Clinical Pharmacology, University of Newcastle upon Tyne.

Dr Dima Abdulrahim.

Research Briefings Manager

National Treatment Agency

Lord Victor Adebowale

Chief Executive, Turning Point.

Mr Martin Barnes

Chief Executive, DrugScope.

Dr Margaret Birtwistle

Specialist General Practitioner, Senior Tutor—Education and Training Unit, St George's Hospital and Forensic Medical Examiner.

Reverend Martin Blakeborough

Director, Kaleidoscope Drugs Project, Kingston upon Thames.

Dr Cecilia Bottomley

Specialist Registrar in Obstetrics and Gynaecology, London.

Ms Carmel Clancy

Principal Lecturer in Mental Health and Addictions, Middlesex University.

Professor Ilana Crome

Professor of Addiction Psychiatry, Keele University Medical School, Harplands Hospital.

Ms Robyn Doran

Registered Mental Health Nurse and Service Director, Substance Misuse, Central and North-West London Mental Health Trust.

Ms Dianne Draper

Public Health Policy Support Officer, Government Office for Yorkshire and Humberside.

Mr Robert Eschle JP

Local Councillor and Magistrate, Kent.

Ms Vivienne Evans

Chief Executive, ADFAM.

Professor C Robin Ganellin FRS

Emeritus Professor of Medicinal Chemistry, University College London.

Dr Clare Gerada

General Practitioner, London and Primary Care Lead for Drug Misuse, Royal College of General Practitioners.

Mr Patrick Hargreaves

Drugs and Alcohol Advisor, Durham County Council Education Department.

Mr Paul Hayes

Chief Executive, National Treatment Agency.

Mr Andrew Hayman

Assistant Commissioner of the Metropolitan Police, and Chair of the Association of Chief Police Officers Drugs Committee.

Mr Russell Hayton

Clinical Nurse Specialist and Clinical and Services Governance Manager, Plymouth Drug and Alcohol Action Team.

Ms Caroline Healy JP

Director, ChildLine and Magistrate, London.

Dr Matthew Hickman

Deputy Director, Centre for Research on Drugs and Health Behaviour, Senior Lecturer in Public Health, Bristol University.

Mr Alan Hunter

Director, Law Regulatory & Intellectual Property and Secretary to the Association of British Pharmaceutical Industry.

Professor Leslie Iversen FRS

Professor of Pharmacology, Oxford University.

His Honour Judge Thomas Joseph

Resident Judge, Croydon Crown Court.

Professor Michael Lewis

Professor of Oral Medicine, Cardiff University.

Dr John Marsden

Research Psychologist, Institute of Psychiatry, London.

Mr Peter Martin

Former Chief Executive, Addaction.

Mrs Samantha Mortimer

Head of Personal, Social and Health Education and Citizenship, St Paul's Catholic High School, Manchester.

Professor David Nutt

Professor of Psychopharmacology, Bristol University.

Dr Richard Pates

Consultant Clinical Psychologist and Clinical Director, Community Addiction Unit, Cardiff.

Mr Trevor Pearce

Acting Director General, National Crime Squad.

Mr Howard Roberts

Deputy Chief Constable, Nottinghamshire Police.

Mrs Kay Roberts

Pharmacist, Glasgow

Dr Mary Rowlands

Consultant Psychiatrist in Substance Misuse, Exeter.

Dr Polly Taylor

Veterinary Surgeon, Cambridgeshire.

Ms Monique Tomlinson

Freelance Consultant in Substance Misuse, London.

Mr Arthur Wing

Assistant Chief Officer, Sussex Probation Area.

Annex B


Professor David Nutt FMedSci (Chairman)

ACMD member

Mr Martin Barnes

ACMD Member

Professor Geoff Phillips

Advisor to the Home Office

Dr Clare Gerada

ACMD Member

Dr Noel Gill

Public Health Laboratory Service

Professor CR Ganellin FRS

ACMD Member

Alan Hunter

ACMD Member

Dr S L H Thomas

Reader in Clinical Pharmacology, University of Newcastle upon Tyne

National Poisons Information Service (Newcastle Regional Drugs and Therapeutics Centre)

Dr Les King

Advisor to the Home Office

Former Head of Drugs Intelligence Unit (Forensic Science Service)

Kay Roberts

ACMD member

Dr Polly Taylor

ACMD member

Dr Dima Abdulrahim

ACMD member

Dr Margaret Birtwistle

ACMD member

Robert Eschle

ACMD member

Dr Tom Gilhooly

General Practitioner

Professor Leslie Iversen FRS

ACMD member

Matthew Hickman

ACMD member

Baroness Ilora Finlay

Professor of Palliative Medicine, Cardiff

Annex C



  (1)  Following the publication of the Council's 2002 report on cannabis the issue remained a standing item on the agendas of both the Council and its Technical Committee.

  (2)  At its meeting in October 2004 the Technical Committee invited Dr Stanley Zammit—who had undertaken further analysis of the Swedish conscripts of 1969 historical cohort study—to attend and to provide an overview of the relationship between cannabis use and psychotic illness.

  (3)  In March 2005, the Home Secretary wrote to the chairman of the Council, seeking advice on recent evidence (published since its 2002 report) about the effects of cannabis on mental health. He also asked the Council for advice on the alleged increase in potency of cannabis products currently available.

  (4)  At its meeting in May 2005, the Council agreed to a process by which it would review the available evidence and appointed a Steering Group (comprising the chairman of the Council, the chairman of the Technical Committee, Professor Leslie Iversen, Mrs Kay Roberts, Dr Matthew Hickman, Dr John Macleod and Dr Leslie King) to undertake the detailed planning on its behalf.

  (5)  The Steering Group, through the secretariat, commissioned the preparation of additional information:

    —  Forensic Science Service: An Update on Cannabis Potency;

    —  Dr Matthew Hickman: Cannabis and schizophrenia: model projections and impact of the rise in cannabis on historical and future trends in schizophrenia (England and Wales);

    —  Home Office: FRANK statistics;

    —  National Poisons Information Service: Enquiries relating to suspected cannabis toxicity;

    —  British Crime Survey: (Then) unpublished data on cannabis use (2004-05).

  (6)  With the assistance of the Council's secretariat, the Steering Group also undertook the identification and retrieval of the relevant published literature on the effects of cannabis on mental health, and the potency of THC in cannabis products.

  (7)  The Steering Group invited the submission of evidence from interested parties. These included specific requests to individuals in the UK, and overseas, who were known to have expertise in the area; as well as arrangements to consider unsolicited submissions (including those made directly to the Home Secretary) from both special interest groups and the general public.

  (8)  The Steering Group invited, on behalf of the Council, selected outside experts and representatives of voluntary organisations to present their data or views at a special meeting of the Council convened on 23 September 2005. Those invited to give oral evidence are identified in the Council's final report (at Annex 3 of that report).

  (9)  The Steering Group also asked five additional experts (in psychiatry, epiemiology and statistics) to attend the special meeting of the Council and to act as additional scientific advisors. These individuals are identified in Annex 2 of the Council's report.

  (10)  All relevant written material submitted to the Council, including submissions and letters from the special interest groups and general public, was included in a 500+ page pack of papers and sent to Council members, and to the five expert advisors, well in advance of the special Council meeting in September 2005.

  (11)  The day after the special open meeting of the Council, a closed session was held to consider the evdience and draw provisional conclusions. Those attending this session were limited to the Council members, the five additional expert advisors, a limited number of relevant officials and the secretariat.

  (12)  The Steering Group took responsibility for drawing up the draft report which was considered by the Technical Committee, and the full Couincil, at their meetings on 3 and 24 November (respectively). The final report was sent to the Home Secretary in December with a covering letter from the Council's chairman.

Annex D


  (1)  Following the receipt of the Permanent Secretary's request the Technical Committee undertook a preliminary examination of the global misuse of methylamphetamine at its meeting on 11 March 2004. This was informed by a presentation from Dr John Marsden and Dr Mike Farrell (Institute of Psychiatry, London). The Committee recommended to Council that, despite the lack of evidence of widespread misuse in the UK, a detailed assessment should be undertaken.

  (2)  At its meeting on 1 April 2004, the presentation by Drs Marsden and Farrell was repeated to the full Council who decided to establish a Working Group, under the immmediate jurisdiction of the Technical Committee, to investgate the matter further and to draft a report for Council.

  (3)  The Working Group met on three occasions between April and September 2004. The evidence base constructed by the Working Group was as follows:

    —  a review of the relevant scientific literature;

    —  additional (unpublished) reports provided by:

—  National Criminal Intelligence Service: Misuse of Pharmaceutical Products in the Illicit production of Methylamphetamine;

—  Forensic Science Service: Chemistry, Seizure Statistics<Analysis, Synthetic Routes and History of Illicit Manufacture in the UK and USA.

    —  oral evidence from:

—  Professor Charles Marsden: Pharmacology of methylamphetamine;

—  Dr Val Curran: Literature Review of Methylamphetamine;

—  Mr Ronald Geer: Experience of Methylamphetamine Misuse in the US;

—  Professor Robin Murray: Drug induced psychoses;

—  Dr Judy Miles: Treament Issues.

  (4)  The Working Group's draft report was considered by the Technical Committee in October 2004, and by the Council, in November 2004. At the request of the Council the Working Group was asked to undertake additional work. The Working Group met on one further occasion and its final report was considered by Council in April 2005. After amendments, the report was sent to the Home Secretary who accepted the Council's advice in full.

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