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History of Methadone
The
history of methadone and methadone prescribing
Understanding
the history of responses to opiate use puts into context the
prescribing policies we see today - and may help us anticipate
the future. Starting
with the first organised responses to opiate use in the UK this
section describes the influences on policy and practice, including
those from the USA, the history of the discovery of methadone
and the development of its unique role in the treatment of opiate
use. The
services offering a treatment response to opiate use that are
currently available in the UK are then described in the light
of the historical background. The
origin of legal controls
Growing
international concern about opiate use led to the First Opium
Convention in the Hague in 1912. Britain as a signatory agreed
to the principle of adopting controls over opium, morphine and
cocaine.1 In
July 1916, following rumours that soldiers on leave were using
cocaine, a 'Defence of the Realm Regulation' was enacted making
it illegal to possess cocaine unless prescribed by a doctor. In
1920 and 1923 the list of drugs that were illegal to possess,
import or sell was expanded by the Dangerous Drugs Acts to include
opium and opium derivatives such as heroin. Doctors could still
prescribe these drugs, but each prescription could only be for
a maximum of three collections from the pharmacy. This
caused some concern among doctors because it left them unclear
as to when prescribing these drugs was legitimate and was seen
as Home Office interference with medical autonomy. In
1924 the Ministry of Health set up a committee, chaired by Sir
Humphrey Rolleston, to look into these issues. The
Rolleston report It
recommended that two groups receive treatment with morphine
or heroin, namely: Those
who are undergoing treatment for the cure of addiction by the
gradual withdrawal method, and When
the first statistics were compiled in 1935 they counted 700
'addicts'. About one sixth of these were medical practitioners.
This size and pattern of addiction remained similar through
the 1930s, '40s and '50s. In 1959 there were 454 known addicts
of whom the majority (204) were addicted to morphine, 68 to
heroin and 60 to methadone. 76% had become addicted following
treatment for pain and 15% were health professionals.2 The
discovery of methadone However
the powerful analgesic action of pethidine was much needed during
the Second World War. It was being produced commercially by
19393 and at the height of the war in 1944 annual production
had risen to 1600 kg.4 Meanwhile
close colleagues Max Bockmühl and Gustav Ehrhart were working
on compounds with a similar structure to Dolantin in the hope
of finding:
This
myth has been widely expanded to attributing one of methadone's
first trade names - Dolophine - to being a derivation of Adolf
and even that it was called Adolophine in Germany - the 'A'
being dropped after the war. In fact the name Dolophine was
created for the drug as a trade name after the war by the Eli-Lilly
pharmaceutical company in America. It was probably derived from
the French dolor (pain) and fin (end).6 The
discovery of 'Hoechst 10820': methadone It
has been asserted that because the new compound's two-dimensional
structure had no resemblance to morphine its pain-killing properties
were not recognised until after the war had ended.6 But although
the town of Hoechst was extensively bombed during the war the
I G Farbenindustrie factory suffered only slight damage and
so limited experimental work was able to continue, stopping
only when supplies of coal ran out or when the rail links were
broken. In the autumn of 1942, after it had been determined
that the drug was both an analgesic and a spasmolytic, it was
handed over to the military for further testing under the code
name Amidon.8 There was no attempt to try and get polamidon
production levels up to those of pethidine. Construction continued
at Hoechst on a new pethidine production plant.4 After
the war In
1945 The Kleiderer report was published by the US Department
of Commerce Intelligence. For the first time in print it reported
the findings of Bockmühl and Ehrhart; and that despite
having a different structure, polamidon closely mimicked the
pharmacological action of morphine.9 The
formula was distributed around the world and exploited by many
companies, which is why it has so many different trade names.
As a result this production of analgesics, which was no longer
commercially viable, practically stopped at Hoechst after the
war. The pethidine plant, by then half finished, was instead
dedicated to the production of penicillin.4 The I G Farbenindustrie
empire was broken up by the allies and the plant that had developed
methadone became part of a new company called Hoechst A G. Eli-Lilly
and other American and UK pharmaceutical companies quickly began
clinical trials and commercial production of the new drug, polamidon. In
1947 Isbell et al, who had been experimenting extensively with
methadone, published a review of their experimental work with
humans and animals and clinical work with medical patients.10
They gave volunteers up to 200mg 4 times daily, and found rapidly
developing tolerance and euphoria. They had to reduce levels
with patients on these high doses because of, among other things:
'...signs of toxicity ... inflammation of the skin ... deep
narcosis and ... a general clinical appearance of illness.'
They also found that 'morphine addicts responded very positively.'
They concluded that methadone had high addiction potential:
'We believe that unless the manufacture and use of methadon
[methadone] are controlled addiction to it will become a serious
health problem.' There
were many early studies all of which found methadone to be an
effective analgesic. Bockmühl and Ehrhart were not able
to submit the preliminary research results that they had given
to Kleiderer on the 60 or so compounds they had discovered in
the 'new class of spasmolytic and analgesic compounds' until
July 1948. They were published in 1949.11 Early
advertisements claimed that Physeptone (Wellcome's trade name
for methadone) carried 'little risk of addiction' and the consensus
was that it was a better analgesic than morphine. It is therefore
likely that the first people who became dependent on it had
either been treated for pain or treated by doctors who thought
it to be less dependency-forming than other opiates. In
1955 the Home Office was aware of 21 methadone addicts; by 1960
the number had risen to 60.2 In 1968 when the present Home Office
notification system was set up the first two notifications arrived
on 1 January: a 19 year-old female from London SW12 and a 20
year-old male from London SE23. By the end of the year 297 people
had been notified as addicted to methadone.13 In 1969, as a
result of the setting up of clinics (see below) the number of
people reported as using methadone had risen to 1687.14 The
1960s In
the early 1960s the number of opiate addicts increased and the
pattern of use began to change: there were younger people and
more people taking opiates for pleasure rather than as part
of medical treatment. Heroin
first overtook morphine as the most notified drug of addiction
in 1962.15 Most of these 'new' addicts lived in London. All
of the heroin was pharmaceutically pure and much of it was prescribed
by a small number of doctors. There
was concern that, contrary to the principles of the Rolleston
report, some doctors were showing little, if any, inclination
to 'make every effort for the cure of addiction'. This concern
led to the recall of the Committee on Drug Addiction in 1964. The
second Brain report
The
late 1960s In
1968 the new drug clinics began operating. Their establishment
attracted a large population of opiate users into contact with
the service and the number of notified addicts rose to 2881
of whom 2240 were addicted to heroin. The clinics were set up
to: By
the end of 1969, in central London, diverted supplies of injectable
methadone, mostly in the form of Physeptone ampoules and 10mg
diamorphine tablets, were huge. These tablets were known as
'Jacks' which is the origin of the phrase 'Jacking up'. Indeed
Physeptone ampoules were so easily available on the black market
that they were used: The
1970s The
clinics started to doubt the efficacy of prescribing the client's
drug of choice as a way of producing change. Clinic prescribing
practice moved away from predominantly prescribing injectable
heroin towards prescribing oral methadone, on the basis that
it was more therapeutic to prescribe a non-injectable drug and
because its long half-life meant it could be taken once daily
rather than every few hours. A
landmark study from that time (and the only randomised controlled
trial in this area) compared the effects of randomly allocating
heroin users to either of these two treatments.16 The study,
carried out by Martin Mitcheson and Richard Hartnoll between
1971 and 1976, found that methadone treatment produced more
polarised effects than heroin treatment. The methadone group
were more likely to leave treatment but were also more likely
to achieve abstinence. The heroin group were more likely to
stay as they were. The researchers concluded that: 'The
provision of heroin maintenance may be seen as maintaining the
status quo, although ameliorating the problems of acquiring
drugs ... by contrast the refusal to prescribe heroin (and offer
oral methadone instead) may be seen as a more active policy
of confrontation that is associated with greater change.' As
the results of this study became available the clinics were
starting to deal with a new and different client group: large
numbers of working-class heroin users who were smoking rather
than injecting the relatively cheap heroin that had appeared
on the market from the Middle East. In
the light of the changing client group - who were not asking
for injectable drugs - and the results of the study, the clinics
defined their role as one of promoting change and increasingly
moved towards the use of oral methadone. The
shift away from maintenance prescribing The
1980s This
great increase in the early 1980s differed from that of 20 years
earlier, in that it was not restricted to London: it occurred
all over Britain and many of these new users smoked their heroin
(known as 'chasing the dragon') rather than injecting it. The
prescribing response was largely one of methadone mixture detoxification
programmes - the 'gradual withdrawal method' of the Rolleston
report. However
the increase in the number of opiate users meant that services
had to expand and become more widely available. Prompted by
this change and the Advisory Council on the Misuse of Drugs
(ACMD) Report on Treatment and Rehabilitation19 the Government
responded with a funding initiative which saw the development
of a non-statutory drug service and/or a Community Drug Team
in most health districts. Most of these new services got involved
in methadone prescribing either by employing a clinical assistant
or a consultant psychiatrist on a sessional basis to prescribe
methadone, or through working with GPs. AIDS
and the re-emergence of maintenance prescribing The
1988 report of the Advisory Council on the Misuse of Drugs (ACMD)
on AIDS and drug misuse20 Part 1 led to the development of community-based
needle and syringe exchange schemes all over Britain. The
report articulated the policy of directing treatment towards
abstinence by achieving intermediate goals such as:
The report advocated a comprehensive approach to the prevention
of the spread of HIV, following its first conclusion that: '...HIV
is a greater threat to public and individual health than drug
misuse. The first goal of work with drug misusers must therefore
be to prevent them acquiring or transmitting the virus. In some
cases this will be achieved through abstinence. In others, abstinence
will not be achievable for the time being and efforts will have
to focus on risk reduction. Abstinence remains the ultimate
goal but efforts to bring it about in individual cases must
not jeopardise any reduction in HIV risk behaviour which has
already been achieved.' This
reversed the abstinence-orientated prescribing policy of the
preceding years as it legitimised longer-term prescribing to
enable users to stop injecting. Although there was a wider range
of prescribing options supplementing short-term detoxification,
most doctors continued to prescribe methadone mixture only for
limited periods of time. In
time it transpired that the high HIV infection rates in Edinburgh
were a local phenomenon resulting from factors such as unavailability
of injecting equipment, and were not being replicated across
Britain.21, 22 However the services that were set up on the
assumption that these HIV prevalence rates were typical have
almost certainly been instrumental in maintaining relatively
low rates of HIV seroprevelance among injecting drug users. The
opposition to methadone maintenance prescribing In
Merseyside some doctors revived the prescribing of heroin in
injectable and smokeable forms. The
1980s conflict over prescribing policy led many to regard as
a cause célèbre the disciplining of Dr Anne Dally
who had espoused maintenance prescribing. The General Medical
Council found Dr Dally guilty of 'serious professional misconduct'
because she had 'irresponsibly treated addicts privately by
providing methadone in the long term without reasonable medical
care.' Some saw this as punishment by the medical establishment
for her policy of maintenance prescribing and prescribing of
injectables as part of private practice.25, 26 The
American experience
The American experience shows that treating patients with the
same medication can be viewed and executed in very different
ways, and that these may be as important as the drug itself
in determining the effects of treatment. From
the First World War onwards American and British drug policies
took very different directions. In the USA in 1914 the Harrison
Act controlled the sale and possession of drugs. It contained
references to the prescription of addictive drugs for 'legitimate
medical purposes ... prescribed in good faith'. However in 1922
the Behrman case, in stark contrast to UK policy, determined
that it was a crime for a physician to prescribe a narcotic
drug to an addict. By
1938 approximately 25000 doctors had been prosecuted on narcotics
charges and 3000 had served prison sentences! Federal agents
relied heavily on the testimony of drug users to secure these
convictions - they secured these testimonies by supplying the
users with small quantities of drugs.6 Understandably this resulted
in doctors having very little to do with the treatment of addiction. After
the Second World War there were just two large drug treatment
facilities providing in-patient treatment to 'help addicts abandon
drug taking'. The one at Fort Worth in Texas offered a service
to men who lived west of the Mississippi and the one in Lexington
in Kentucky served men east of the Mississippi and women from
the entire USA. The
first use of methadone in the treatment of opiate dependence In
the early 1960s Dr Marie Nyswander and Dr Vincent Dole, a respected
American psychiatrist and research scientist, had found that
they could not stabilise opiate users on morphine without continually
increasing the dose. They reviewed the medical literature in
search of possible alternatives and pioneered the radical step
of prescribing methadone which was effective orally, and seemed
from pain research and some detoxification experience to be
longer acting (they were not able to measure blood levels in
those days). They soon found that once they had reached an adequate
treatment dose that they could maintain people on that dose
for long periods of time. Dole
encountered powerful resistance from the US Bureau of Narcotics
whose agents told him that he was breaking the law and that
they would 'put him out of business'. In view of the past history
of doctors' experiences in court he took the brave step of inviting
them to prosecute so that a 'proper ruling on the matter could
be made' - they declined. Nyswander
and Dole: the pioneers of American methadone maintenance Nyswander
and Dole based their approach on the theory that, once addicted,
opiate addicts suffer from a metabolic disorder, similar in
principle to metabolic disorders such as diabetes. Just as insulin
normalises the dysfunction in diabetes, so methadone was proposed
to normalise the dysfunction of opiate addiction. They argued
the necessity for large doses of methadone (80mg to 150mg) to
establish a 'pharmacological blockade' against the effects of
heroin, that would prevent addicts from experiencing euphoria
if they took it. Even
though Nyswander and Dole viewed methadone treatment as a physical
treatment for a physiological disorder, their initial attempts
to use methadone maintenance were combined with intensive psycho-social
rehabilitation. Many of their patients clearly derived great
benefit from this innovative treatment.27 The
spread of methadone maintenance programmes The
medical treatment was - and is - encased in a rigid delivery
system. In most programmes patients attend the programme daily
to drink their methadone and are regularly monitored through
testing of urine samples (the collection of which is supervised)
and counselling. Some programmes offer a variety of help and
psycho-social treatment from group therapy to help in finding
jobs. Once patients are stabilised they are able to earn the
'privilege' of taking home doses of methadone for one or more
days. The
numbers of patients receiving Methadone Maintenance Treatment
(MMT) in the USA rose: in 1992 there were about 120000 patients
served by around 800 programmes. There is a great deal of variation
in the rehabilitation and psycho-social services that are offered
in addition to methadone and also in the dosage levels employed.
Over half of patients receive below 60mg daily - which is accepted
in the USA as the therapeutic minimum28 - well below the level
recommended by Nyswander and Dole's research. Prescribing
services available in the UK today
There are also a small number of doctors who offer treatment
to drug users as part of:
They
do not usually have in-house testing facilities such as urinalysis,
but primary health care teams increasingly have staff such as
counsellors in their surgery. GPs
vary considerably in their attitudes and practice in treating
drug problems. If a GP is not inclined to prescribe methadone
for an opiate user there is little that can be done to force
them because doctors are able to use considerable discretion
in deciding what they think is the best treatment for their
patients. Street
agencies: easy-reach, often non-statutory services Community
drug teams (CDT) Drug
clinics Clients
may have to attend on a daily basis or several times a week
to obtain their prescriptions. In some cases, usually 'low threshold
methadone maintenance programmes', they may be required to drink
their methadone at the clinic in front of a member of staff. To
cope with the large volume of prescription writing most clinics
use a computer to generate prescriptions - see Section 5: methadone
and the law, handwriting exemptions. These prescriptions may
then be sent to retail pharmacies for dispensing. Alternatively,
methadone may be dispensed from a local hospital pharmacy as
this is often cheaper. Drug
clinics may have access to specialist in-patient facilities
for detoxification and other in-patient treatments. Some clinics
have facilities for dispensing methadone to patients who have
to attend daily to receive their medication. Drug clinics usually
offer a variety of treatment options. Large
centre prescribing is often an essential part of a service to
a large number of opiate users, hence their predominance in
large cities. Private
practice In
general, private services are preferred by clients who are in
full-time employment, and appreciate the shorter waiting times,
increased doses and willingness to prescribe on a maintenance
basis.
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