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Document level: Clinical Service Line (CSL)
Code: DA8
Issue number: 2
Methadone mixture prescribing guidance
Lead executive
Authors details
Lead Clinical Director
Locality Clinical Director Cheshire East Substance Misuse Service
Type of document
Target audience
Guidance
All clinical staff
To provide guidance for prescribing methadone in a community setting as a
treatment for opiate dependence
Document purpose
Approving meeting
Implementation date
Medicines Management Group
Jun-16 followed by an annual compliance review
17-Jun-15
CWP documents to be read in conjunction with
DA4
Buprenorphine and Buprenorphine Naloxone combination (Suboxone®) prescribing
guidance
DA5
Guidance for the management of community opiate detox
Standard Operating Procedure; Management of Patients who choose to miss
appointment with doctor, keyworker or nurse
Document change history
What is different?
Appendices /
electronic forms
What is the impact of
change?
Training
requirements
New Document
New Document
New Document
No - Training requirements for this policy are in accordance with the CWP
Training Needs Analysis (TNA) with Learning and Development (L&D)
Document consultation
Prescribers and Clinical Directors across Community Drug Teams, Sally
Sanderson; Jane Tyrer; Kate Chapman; Karen Millard; Laura Draper; Mark
East locality
Grey; Nichola Spinney; Jenny Jones; Carole Winstanley; Susan Griffiths;
Linda Johnstone; Toby Biggins; Terry Unwin
Prescribers and Clinical Directors across Community Drug Teams, Jan Pye;
Rashmi Parhee; Jose Ferran; Geraldine Swift; Joanne Hurley; Neal Fenna;
Wirral locality
Linda Friend; Iain Wells; June Thornton; Polly Nash; Jugnu Bothra; Iris
Batman; Angela Davies
Prescribers and Clinical Directors across Community Drug Teams, Joanne
Knowles; Joy Fenna; Daniel Carlson; Dave Appleton; Colin White; Mike
Caulfield; Jane Newcombe; Pauline Forrester; Carys Jones; Karen Phillips;
West locality
Gwen Jones; Catherine Phillips; Dave Donal; Helen Thornley-Jones; Jean
Brennan; Jan Patton; Janet Lomas; Sarah Evans; Susan Rawson; Christina
Theobald; Alison Woodhouse; Dr Vikram Palanisamy
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Document consultation
Abiola Allinson; Chris Sheldon; Fiona Couper; Gill Monteith; Jane Manton;
Audrey Jones; Jo Watts; Jenny Gillison; Lyn Ellis; Martin Dowler; Pat
Mottram; Tracey Battison; Veena Yadav; Alison Wood; Melysa Cureton;
Corporate services
Karen Herbert; Joanna Rogerson; Jan Devine; Sally Bestwick; Amanda
Miskell; Lynn Barton; Helen Pilley; Ken Edwards; Helen Davies; Jen Adams;
Kath Jones, Steven Buckley
Financial resource
implications
None
External references
1. National guidelines for the management of substance misuse: Department of Health (2007).
Drug misuse and dependence: guidelines on clinical management 2007; (The Orange Book)
2. Royal College of General Practitioners (2011). Guidance for the use of substitute prescribing in
the treatment of opioid dependence in primary care;
3. NICE (2007). Methadone and buprenorphine for the management of opioid dependence. NICE
Technology appraisal guidance 114;
4. NICE (2007). Naltrexone for the management of opioid dependence. NICE Technology appraisal
guidance 115;
5. NICE (2007). Drug misuse: psychosocial interventions. National clinical practice guidelines 51;
6. NICE (2008). Drug misuse; opioid detoxification. National clinical practice guidelines 52;
7 ACMD (2000). Reducing drug related deaths.
8 eBNF – www.bnf.org
Equality Impact Assessment (EIA) - Initial assessment
Yes/No Comments
Does this document affect one group less or more favourably than another on the basis of:
No
 Race
No
 Ethnic origins (including gypsies and travellers)
No
 Nationality
No
 Gender
No
 Culture
No
 Religion or belief
No
 Sexual orientation including lesbian, gay and bisexual people
No
 Age
 Disability - learning disabilities, physical disability, sensory
No
impairment and mental health problems
Is there any evidence that some groups are affected differently?
No
If you have identified potential discrimination, are there any exceptions valid, legal and/or justifiable?
N/A
Is the impact of the document likely to be negative?
No
N/A
 If so can the impact be avoided?
 What alternatives are there to achieving the document without
N/A
the impact?
N/A
 Can we reduce the impact by taking different action?
Where an adverse or negative impact on equality group(s) has been identified during the initial
screening process a full EIA assessment should be conducted.
If you have identified a potential discriminatory impact of this procedural document, please refer it to
the human resource department together with any suggestions as to the action required to avoid /
reduce this impact. For advice in respect of answering the above questions, please contact the
human resource department.
Was a full impact assessment required?
No
What is the level of impact?
Low
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Content
1.
2.
3.
4.
4.1
4.2
4.3
4.4
4.5
4.6
4.7
4.8
4.9
5.
5.1
6.
6.1
6.2
6.3
6.4
6.5
Introduction ................................................................................................................................... 5
Rationale for the use of methadone .............................................................................................. 5
Pharmacology ............................................................................................................................... 5
Prescribing .................................................................................................................................... 6
Indications..................................................................................................................................... 6
Contraindication ............................................................................................................................ 6
Formulation ................................................................................................................................... 6
Cautions ....................................................................................................................................... 6
Side effects ................................................................................................................................... 6
Interactions ................................................................................................................................... 7
Pregnancy..................................................................................................................................... 7
Breast feeding ............................................................................................................................... 7
Assessment .................................................................................................................................. 7
Starting methadone....................................................................................................................... 7
Induction ....................................................................................................................................... 8
Continuing treatment ..................................................................................................................... 8
Missed doses ................................................................................................................................ 8
Missed appointments .................................................................................................................... 9
Monitoring treatment, including drug testing .................................................................................. 9
Reducing and finishing treatment .................................................................................................. 9
Methadone and driving ................................................................................................................. 9
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Quick reference flowchart for patient asking for help with drug dependence
For quick reference the guide below is a summary of actions required.
Patient presents asking for help with drug dependence
Assessment
Establish patient is dependent on opiates







Keyworker assessment
Urine samples
Obtain a GP summary
Complete risk assessments
Consider safeguarding
Introduce Harm reduction
Review CareNotes

Emphasise that methadone is
only an enabler
Emphasise that the patient needs
to work towards recovery
Explain missed appointment
policy
Give out Methadone Handbook

Key worker agrees action / careplan with patient
Establish that methadone is the appropriate Oral
Substitute Therapy (OST)


Appointment with prescriber
Appointment with Harm Reduction Team
Agreement about treatment plan


Start methadone prescribing
Discuss the dangers of starting
methadone
Explain the patients responsibility
to tell the DVLA as well as other
health carers of the methadone
prescription
Start low and slow 20-30mg normally observed
consumption
Increase in steps max 30mg in a week until patient stable
Bear in mind treatment doses are 60120mgs
Monitor progress through keyworker and prescriber
appointments
Facilitate recovery activities
Achieve stability and relax pick up regimes
Help patient into recovery
When appropriate begin reduction and stopping
treatment as per Guidance for the management of
community opiate detoxification
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1.
Introduction
This guidance is for drug workers and prescribers working for Cheshire and Wirral Partnership NHS
Foundation Trust (CWP) substance misuse services and general practitioners working in shared care
programmes. It should be read in conjunction with the above national documents and following local
guidance:
Drug service documents:
 Standard Operating Procedure; Management of Patients who choose to miss appointment
with Doctor, keyworker or nurse [1];
 Guidance on the principles and practice of substance misuse treatment;
 Morphine sulphate sustained release capsules (MXL) prescribing guidance;
 Naltrexone prescribing guidance;
 Injectable methadone prescribing guidance;
 Injectable diamorphine prescribing guidance;
 Guidance for the care of pregnant women who have a drug problem;
 Guidance on the management of benzodiazepine use and dependence;
 Guidance for stimulant detoxification (cocaine) within the drug and alcohol clinical
management unit;
 Guidance on the management of alcohol problems.
2.
Rationale for the use of methadone
The National Institute for Health and Care Excellence, Department of Health and Royal College of
General Practitioners all see methadone as an effective substitute medication that can be part of the
treatment of opioid dependence leading to recovery. This is backed up by a large body of evidence.
From the moment a patient presents to our Community Drug Teams the process must be focused on
enabling the patient to achieve recovery. The assessment process and the first 4-6 weeks of
engagement must be intense and should result in that patient and the key worker mutually formulating
a careplan. It must be emphasised at all stages that methadone on its own is no more than an
“enabler” allowing the patient to focus on working towards recovery without the distractions and chaos
of illicit drug use.
The UK Drugs Policy Commission defines recovery as:
 Recovery is a process, characterised by voluntarily maintained control over substance use,
leading towards health and well-being and participation in the responsibilities and benefits
of society.
3.
Pharmacology
Mode of action
 Methadone is a long acting synthetic opioid analgesic originally synthesised in 1939.
 It acts as a full opiate agonist.
 Methadone alleviates opioid withdrawal symptoms and at adequate doses blocks the
effects of additional opioids, while at the same time alleviating craving.
Clinical features
 Peak plasma concentration occurs two to four hours after a first dose; and to two to six
hours after regular administration.
 It takes four to five days for methadone tissue and plasma levels to stabilise, though
accumulation continues beyond this, finally reaching a steady state by ten days.
 Once a steady state is reached variations in blood concentrations are small.
Metabolism
 It is well absorbed from the gastrointestinal tract into the blood stream.
 It is well distributed in body fats
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
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It is metabolised through the liver. This is via the cytochrome P450 sub family of enzymes
and is therefore susceptible to interactions with drugs that inhibit or induce liver enzymes.
(see interactions)
It binds well to plasma protein and to lung, liver and kidney tissue.
Methadone metabolism varies enormously in different people. Widely different doses of
methadone are needed to create the same serum methadone level.
The products of methadone are excreted principally in the faeces and urine.
4.
Prescribing
The following is a summary of the BNF sections covering methadone, 4.7.2 opioid analgesics and
4.10.3 opioid dependence, and national guidelines applying to those prescribing methadone in CWP
drug and alcohol service.
4.1
Indications
The patient is opiate dependent and agrees to methadone treatment, its conditions and monitoring
arrangements.
Methadone should be prescribed as an adjunct in treatment of opiod dependency where detoxification
is not seen to be appropriate.
The patient has no medical contraindications
4.2
Contraindication
As with any opiate, methadone is contraindicated in acute respiratory depression, when there is a risk
of paralytic ileus, and in association with acute head injury.
Methadone should be avoided or prescribed with great caution in patients with severe symptomatic
liver disease and hepatic impairment or severe kidney disease or renal failure.
4.3
Formulation
Methadone Mixture 1mg/ml and 10mg/ml and Methadone Injection 25mg/ml 2ml ampoule and
50mg/ml 1 ml ampoule are listed in the BNF in the opiod dependence section 4.10.3. Methadone 5mg
tablets and other ampoule sizes are listed in the opiod analgesics section 4.7.2.
Methadone Mixture 1mg/1ml is the formulation of choice in CWP for oral substitute treatment. This is
in line with licensing, NICE and DH recommendations for the treatment of opioid, particularly heroin,
dependence.
Methadone tablets, methadone concentrate and methadone ampoules should not normally be
prescribed unless there are exceptional circumstances (see specific Trust guidance).
4.4
Cautions
Caution should be exercised in the following circumstances:
 Problematic injecting and multiple substance use;
 Concurrent excessive drinking and alcohol dependence;
 Severely mentally disturbed patients at high risk of deliberate self-harm or harm to others;
 Cardiac, respiratory and renal disease;
 In addition to general cardiac conditions specific attention should be paid to those at risk of
QT interval elongation, e.g. those on other medication which can elongate the QT interval.
(Note methadone use is contraindicated with citalopram and escitalopram)
4.5
Side effects
These are covered in BNF section 4.7.2 but include respiratory depression, constipation, nausea, dry
mouth, hypotension and sweating.
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In section 4.10.3 particular comment is made about over dosage. Methadone even in low doses is a
special hazard to children; non dependent adults are also at risk of toxicity; dependent adults are at
risk of toxicity if tolerance is incorrectly assessed during induction.
4.6
Interactions
The main drug interactions of methadone are associated with:
 Its CNS depressant activity, in particular benzodiazepines antidepressants and alcohol;
 Its liver metabolism;
 Enzyme inducers such as alcohol, tobacco, carbamazepine, phenytoin and rifampicin will
reduce the plasma levels of methadone;
 Enzyme inhibitors such as cimetidine, allopurinol, ciprofloxacin and disulfiram will increase
plasma levels (RCGP recommends Leavitt SB. Methadone-Drug Interactions. Addiction
Treatment Forum 2005);
 Care also needs to exercise with medication that prolongs QTc intervals.
4.7
Pregnancy
Acute withdrawal of opioids should be avoided in pregnancy because it can cause foetal death.
Methadone is recommended in pregnancy because it carries a lower risk to the foetus than continued
use of illicit drugs. If a woman who is stabilised on methadone becomes pregnant therapy should be
continued. Any changes should only be made in the 2nd trimester and then only gradually and
carefully. The neonate needs to be monitored for respiratory depression and withdrawal. Signs of
neonatal withdrawal usually occur within 24-72 hours but can develop as late as 14 days. For full
advice see Service Guidance “Guidance for the care of pregnant women who have a drug problem”.
4.8
Breast feeding
The dose of methadone should be kept as low as possible in breast feeding mothers and the infant
should be monitored for sedation. Any sleepiness, breathing difficulty or limpness in breast fed babies
of mothers taking opioid substitutes should be referred urgently to a healthcare professional.
4.9
Assessment
Methadone is licensed as an adjunct in treatment of opioid dependency.
Therefore no patient should be started on methadone without clear evidence of opiate dependence.
This will involve a full assessment, including a Leeds Dependency Questionnaire and a sample
positive for opiates.
For details of full assessment see Service Guidance “The principles and practice of substance misuse
treatment” for different treatment pathways for opiate dependent patients.
5.
Starting methadone
Before starting methadone the following information should be highlighted:
 Excessive dose of methadone may be poisonous and cause death; either as a one off or
an accumulating dose over several days;
 Methadone may be dangerous when taken with other opioid or sedative drugs, particularly
if one or more drugs are being injected;
 Methadone may affect the capacity of patients to drive or operate machinery, particularly
during the induction stages when the dose is being increased. They should be informed
about their legal requirement to inform the DVLA;
 A summary of their General Practice notes will be requested and their GP will be informed
of the outcome of their assessment, including medication prescribed;
 Clients must be made aware that staff have a duty under the Children Act 1991 to inform
social services and liaise with local multi-agency child protection procedures of any
concerns about a child’s welfare. They also have a duty to visit any client caring for children
at home to assess the home situation. See “Joint Working Protocol between Cheshire West
and Chester Children’s Social Care and Cheshire Drug and Alcohol Services”;
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
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

Patients should be informed that their information might sometimes be used completely
confidentially and anonymously for epidemiology and research purposes;
The agreed treatment programme should be recorded as a care plan in line with Trust
policy and signed by the patient and drug worker. The patient should be given a copy of
their care plan;
Boundaries should be explained and the consequences of breaking these boundaries
should be made clear. See SOP “Management of Patients who choose to miss
appointment with nurse, prescriber or keyworker”;
Any questions should be fully answered and they should be given written information about
the programme (including The Methadone Handbook).
5.1
Induction
The dose of methadone the patient is likely to eventually need depends on a number of factors,
including the amount, frequency and duration of heroin use, mode of use and the metabolism of the
patient. Even after a thorough assessment it is not possible to predict an exact dose. It is widely
recognised that induction on to a script is a high risk time because of the dangers of methadone to
patients with low or no opiate tolerance. It is therefore important to start methadone safely. National
guidelines recommend:
 The approach is to start low and safe. The initial dose of methadone should normally be 10
to 30mg daily. In exceptional circumstances up to 40mg daily can be prescribed;
 Patients start on observed consumption at a community pharmacy;
 The dose can be increased in 5 to10mg increments every 3 to 5 days until a dose is
reached that the patient feels comfortable on, lasts 24 hours, does not cause sedation or
side-effects and helps reduce and stop illicit drug use. The BNF suggests a maximum
increase of 30mgs in one week;
 For some patients an effective dose is in the region of 60 to120mg although many choose
to remain at lower doses;
 Patients should be reviewed within one week of starting treatment and thereafter as
clinically appropriate depending on the level of continuing illicit drug use, associated health
and social problems and whether the dose of methadone continues to be increased.
Generally, the patient will be seen by their drug worker weekly or fortnightly during the first
two months of treatment whilst the patient is stabilising and then 3 monthly when the
patient is stable. The patient should be seen as required by a prescriber depending on
their progress in treatment and associated health problems. As a minimum a patient
should be reviewed by the prescriber within the first month of treatment and subsequently
at least six monthly.
They should continue on observed consumption for as long as deemed necessary to help achieve
stability, bearing in mind the DH recommendation of a minimum of 3 months and the extra cost of
observed consumption.
6.
Continuing treatment
There should be a well-structured care plan using approved and standardised Trust forms and should
include psychosocial components.
Once the patient has been started on methadone and the dose adjusted to an appropriate level the
management plan should be reviewed as to whether the plan is for a detoxification from methadone or
for a period of maintenance.
6.1
Missed doses
Managing missed doses of methadone
Department of Health “Orange Book” states
If patients miss methadone doses for 3 (consecutive) days or more, for whatever reason they need to
be reassessed for intoxication and withdrawal before methadone administration is recommenced. It
may be appropriate to reduce the dose and titrate back up to the original dose if the patient has not
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had methadone for more than three days as their tolerance may be reduced. If patients have
abstained for five days or more they will require an assessment of their tolerance before being reinducted on to methadone.
Therefore action is dictated by number of daily doses actually missed:
If the patient has missed 1 to 2 days doses the community pharmacist may continue current
prescription, unless there are other concerns about the patient or very frequent missing of dispensed
doses.
If the patient has missed 3 days doses or more then the community pharmacist should refer to the
substance misuse service and an assessment should be made of the patient’s presentation and
dosing including a drug use history and dip test urine. If history suggests continued opiate use
(methadone or heroin) and urine test is positive for opiates and or methadone, it is safe in most
circumstances to continue current prescription but the case should be discussed with the service
prescriber. It may be necessary to reduce the dose and titrate back up. If the patient misses a dose on
Friday and over the weekend then the situation needs to be discussed with a prescriber on Monday
before restart.
If the patient has missed 5 or more day’s doses it may not be safe to continue current prescription.
The drug worker should take a drug history and dip test urine. Discuss with service prescriber or
arrange for patient to attend next prescriber’s clinic before continuing prescription.
6.2
Missed appointments
Action should be taken in line with the SOP “Management of patients who choose to miss appointment
with the nurse, doctor or keyworker”. Options include reducing the dose and changing the pickup
regime
6.3
Monitoring treatment, including drug testing
Treatment with methadone should be monitored primarily by improvements in a patient’s drug use,
general health and social wellbeing.
Urine testing should be used to monitor prescribed methadone and as an aid to monitoring illicit drug
use. It should generally be carried out at least twice a year.
6.4
Reducing and finishing treatment
See guidance for management of opiate detoxification. Reducing and completing methadone
replacement treatment should be regularly discussed with the patient. When a patient feels ready for
reducing and stopping they should be supported in doing this and plans made for remaining abstinent
once drug free.
Methadone is usually reduced in 5mg steps every one to two weeks until 30mg and then reduced in 2
mg steps every one to two weeks. Once the patient is down to lower doses the patient should be
reviewed by the keyworker and prescriber and a plan put in place for a final reduction with the addition
of supportive medication (e.g. lofexidine, quinine sulphate, night sedation) plus open access to clinics
until the patient is symptom free.
6.5
Methadone and driving
All patients must be informed prior to commencing treatment that he / she has a legal requirement to
inform the DVLA that they are prescribed methadone. This advice must be recorded in the patient’s
records.
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