An enhanced service to treat substance misuse can bring social benefits as well as significant improvements in health outcomes, as Dr Susannah Harris explains


It is estimated that there are between 150 000 and 200 000 problematic drug users in the UK. So it is likely that most GPs have patients who misuse drugs on their list, although prevalence in urban areas is significantly higher than in rural areas.1

GPs in the UK, unlike their counterparts in other countries, have been treating drug users for decades. Until now, this has been done in a rather unstructured way.2 The new GMS contract provides GPs with a framework for providing treatment for substance misuse and, furthermore, offers relatively good remuneration levels.1

National guidelines on the treatment of drug misuse advise GPs to treat drug misusers in partnership with local drug treatment agencies – an arrangement known as shared care,3 and several excellent shared care schemes have evolved in the past few years.4 Around 38% of GP practices are now providing shared care treatment in the UK.5

Is drug misuse treatment effective?

There is good evidence that treatment of drug misuse improves a range of health outcomes. Perhaps most importantly, treatment of drug misuse has been shown to save lives. Studies show that street heroin users have a mortality rate of up to 17 times that expected.6 Most deaths are directly drug-related, for example overdose, blood-borne virus infection and bacterial infection, and some – violent deaths by suicide and assault – indirectly so.

This life-saving effect is only seen if patients are retained in treatment, however.7,8 In patients discharged early or randomised to placebo, death rates are almost as high as baseline rates.9,10

Drug misuse treatment also improves many other important outcomes. Evidence shows a significant reduction in risky injecting behaviour,11 and transmission of blood-borne viruses.12,13

There is a significant reduction in the use of illicit drugs, including cocaine,13 benzodiazepines and opiates. The rate of opiate use approximately halves with each year of treatment and is directly correlated to dose of substitution therapy.9,14,15 Unfortunately, alcohol use may rise.

Many outcome studies also show improvements in social functioning (Box 1, below).2 The costs of drug misuse include the use of health and social services as well as less quantifiable costs such as relationship breakdown and poor parenting.

Box 1: Main areas of benefit in methadone treatment*
  • Reduced opiate misuse
  • Reduced crime and imprisonment
  • Reduced HIV risk behaviours (injecting)
  • Improved quality of life
  • Improved physical and psychological health
  • Reduced non-opiate misuse
  • Engagement in employment or educational activities
  • Reduced death rate
  • Reduced HIV behaviours (sexual)
* in decreasing order of effect

Which treatment is best?


Methadone maintenance treatment is the most extensively studied and evaluated treatment. Research spanning 30 years and in very different cultures – the USA, Hong Kong, Sweden,Thailand 16,17 – shows consistently positive results. Meta-analysis has reliably demonstrated considerable reduction in harmful behaviour. 18

A Cochrane review concludes that higher methadone doses, of 60-100 mg per day, are more effective than lower doses in retaining patients and reducing use of heroin and cocaine during treatment.14

The recently published 5-year longitudinal prospective cohort study National Treatment Outcome Research Study (NTORS), the first of its kind in the UK, adds further weight to the body of evidence on methadone maintenance treatment and shows that the initial improvements are sustained over a 5-year period so long as treatment continues.19 In addition, it compares methadone reduction therapy with maintenance, and the poor outcomes associated with reduction programmes support the promotion of maintenance (as opposed to abstinence) philosophy.20

A Cochrane review found that while methadone reduction successfully ameliorated withdrawal symptoms, the majority of patients relapse to heroin use.21

Detoxification can even be dangerous, as newly detoxified patients are at greatly increased risk of overdose.22

NTORS also demonstrated a significant positive effect of retention in treatment, which confirms the findings of much research. Large studies from the USA demonstrated a clear relationship between length of time in treatment and improved outcomes. 11 Evidence also shows that discharge must be planned to maintain good outcomes – for unplanned discharges, the beneficial effects disappear as soon as treatment stops.


Buprenorphine treatment is relatively new and less research has been undertaken. In comparisons with methadone as maintenance therapy it has been found to be equally, but no more, effective.23-25 Studies used relatively low doses; it remains to be seen whether further improvements can be made with higher (>=16 mg) doses.

On the other hand, the role of buprenorphine in detoxification from opiates is established; systematic review has shown that withdrawal symptoms are significantly less severe in gradual buprenorphine withdrawal than with the standard non-opioid pharmacological aids to detoxification,26 and are the same or milder than in methadone withdrawal.27

Non-opioid detoxification therapies

The alpha-adrenergic agents clonidine and lofexidine have been used to aid withdrawal from opiates for a number of years, but systematic review does not support their use over that of opioid (methadone or buprenorphine) withdrawal.23 A Cochrane review found no significant difference between clonidine and lofexidine, but lofexidine is better suited to community-based treatment because of the lower incidence of hypotension.28

Preventative therapies

Naltrexone is a complete opioid antagonist which can be taken by the newly detoxified patient to prevent the reinforcing effects of subsequent opiate use. There is a suggestion that it is effective in reducing reincarceration rates, particularly in the wellmotivated. 29

Government guidance recommends hepatitis B immunisation for drug misusers,3,30,31 because they are at higher risk of hepatitis B infection. Past co-infection with hepatitis B can increase the risk of cirrhosis from hepatitis C infection,32 and coinfection with active hepatitis B and C increases the risk of progression to hepatocellular carcinoma.33

Hepatitis A immunisation is also recommended because outbreaks among drug users are common, and hepatitis A co-infection with either hepatitis B or C increases the risk of hepatic failure and death from liver disease.34

Non-pharmacological therapies

Psychological therapies without medication are ineffective, but there is reasonable evidence to show that some sort of supportive sociopsychological therapy enhances the effectiveness of methadone maintenance. 35 However, this effect is lost if counselling approaches are compulsory. 10 A high level of support for individuals maintained on methadone is not cost-effective, but a moderate level is better than a minimal level of support.36

Where should treatment take place?

Reducing drug misuse is one of the key priorities in the NHS Priorities and Planning Framework for 2003-6.37 There is now good trial evidence that drug misuse treatment is equally effective in general practice as in a specialist service in reducing illicit drug use and retaining patients in treatment. One study shows superior hepatitis B immunisation rates in patients treated in primary care.38-40

The Healthcare Commission clearly sees general practice as crucial in achieving these objectives. Last year (2003-4), the percentage of GP practices involved in shared care was one of the performance indicators used to calculate PCT star ratings.5

Setting up an enhanced service

PCTs or those commissioning services for drug action teams will need to negotiate with GP providers to set up enhanced services for drug misuse.

In addition to paying an annual retainer of £1000, the terms of the national enhanced service for treatment of drug misuse reward detoxification (set at £500 per patient per annum for 2003-4) more highly than maintenance treatment (£350 pppa for 2003-4), despite evidence that maintenance is more effective than detoxification. Many PCTs are therefore equalising rates of pay for the two types of treatment.

Notable requirements of the national enhanced service are to hold 6-monthly audits for hepatitis B screening and immunisation and for prescribing of substitute medication. Other requirements recommended by national guidance are:

  • An accurate and up to date register of patients
  • Regular planned review of patients by GP
  • Offering advice on minimising harm
  • Offering drug information and support to families and carers
  • Liaison with other services and teamworking
  • A safe and secure practice, suitable for providing drug services.

Local enhanced services

The lack of detail specified by the new GMS contract offers PCTs the opportunity to tailor local enhanced services contracts which set standards for other evidence-based interventions and find good quality process of care markers to be used in audit and as performance monitoring tools. Audit standards might include:

  • Hepatitis immunisations
  • Ratio of planned to unplanned discharges
  • Offering blood-borne virus pre-test discussions with trained personnel
  • Doses of substitution therapy used in maintenance treatment
  • Markers of good preventative and general medical care, for example screening and immunisations and provision of contraceptive and sexual health services.

Many new local enhanced services will also include elements recommended by national guidance (see above).

A local enhanced service may also be an opportunity to increase access to primary care based treatments by offering an enhanced level of remuneration to practices that treat patients referred from other practices.

Clear protocols to avoid double prescribing, on immunisations and blood-borne virus screening, and for management of conditions that result directly from drug misuse will be needed. PCTs might like to consider offering higher levels of remuneration for GPs who have the skills and are willing to manage drug users with complex needs such as dual diagnosis and pregnancy.

PCTs may wish to tackle the problem of benzodiazepine misuse simultaneously, as monitoring and reviewing benzodiazepine prescribing is a target of the National Service Framework for Mental Health.41,42 They may consider offering additional rewards for successful reduction and detoxification in cases of established dependency.

Training standards should be incorporated into local enhanced services to maintain the skills and knowledge of participating GPs. For many, this will mean taking the RCGP Certificate in Drug Misuse ­ Part 1, or demonstrating equivalent competencies.

Many established shared care schemes are being transferred to local enhanced services with little change in the numbers of GPs participating or the expectations placed on them. Yet demand for treatment is likely to increase significantly.

It is likely that new practices will be encouraged to set up enhanced schemes for drug misuse. Important factors to consider are the impact on practice time and set-up costs, including costs of IT, improved practice security and personal protection training for reception staff (Table 1, below).

Table 1: Impact on practice time of setting up an enhanced service for drug misuse
Time Activity Time spent per 10-20 patients (estimated)
Doctor time

Training, first year

Training, subsequent years

Clinical time, including correspondence

Service development


RCGP Part 1, one day face to face and 4 hours distance learning

6 hours per year

1-2 hours per week

1-2 hours per quarter

1-3 hours per year

Nurse time

Screening and immunisations

BBV pretest discussion

0.5-1 hour per week

0.5 hour per week

Administration time

Correspondence (if treating
non-registered patients)


0.5 hour per week

Depends upon IT capability, likely to be
required twice a year

Funding a drug-dependency worker to assist in running the clinic is generally the responsibility of the commissioning organisation, although local arrangements may vary.

The National Treatment Agency, a special health authority for England tasked with improving drug treatment, is planning to issue a standardised set of Read codes in the near future. This will support clinical management and help to monitor clinical standards. However, monitoring of outcomes is far less well defined nationally, with many tools available and wide variation in use. This may be the subject of some local negotiation.


Drug misuse treatment in general practice is highly effective, evidence based and well supported. Addressing the often serious health needs of this relatively young group of patients and helping to reduce the enormous burden they place on our health, social service and criminal justice systems can be highly rewarding.

Further information

Further practical advice is available from:

Substance Misuse Management in General Practice c/o Bolton, Salford and Trafford Mental Health NHS Trust, Bury New Road, Prestwich, Manchester M25 3BL
Tel: 0161 772 3546, email:, website:

The RCGP Drug Misuse Training Programme Suite 314, Frazer House, 32/38 Leman Street, London E1 8EW
Tel: 020 7173 6090, email:

The programme can give details of your local RCGP regional lead in drug misuse, who will be a highly experienced practitioner in primary care management of substance misuse


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Guidelines in Practice, January 2005, Volume 8(1)
© 2005 MGP Ltd
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