OPIATE MISUSE

1
OPIATE MISUSE

• Will cover
• background information
• treatment aims
• evidence for the use of methadone and
  buprenorphine

2
Illicit drug use in the UK population (2003/04)
UK drug situation Annual report to the EMCDDA
2005

• In the general adult population
• lifetime prevalence of illicit drug use is over a
  third
• 12 of adults have used drugs in the last year
• In young adults (1634 yrs)
• lifetime prevalence of illicit drug use is 47
• 21 have used drugs in the last year
• Males are significantly more likely to use
  illicit drugs than females
• Of 1564 yr olds
• 9.35 per 1,000 are estimated to be using drugs in
  a chronic, potentially damaging way
• 3.2 per 1,000 are estimated to be injecting drugs

3
Treatment aims Drug Misuse and
DependenceGuidelines on Clinical Management
(1999)

• Aims of treatment
• normal health and harm reduction
• reduce or prevent withdrawal symptoms
• stabilise or reduce drug use
• improve lifestyle
• maintain contact with the patient
• Multidisciplinary approach, shared care

4
Management of dependence withdrawal Drug
Misuse and DependenceGuidelines on Clinical
Management (1999)

• Management
• maintenance, usually with opioids e.g. methadone,
  buprenorphine
• withdrawal (or detoxification) with opioids or
  non-opioids, e.g lofexidine
• Careful induction of methadonehigh risk of
  overdose in first 2 weeks
• Dispense on a daily basis, under supervision
  initially
• Monitor progress and review treatment goals
  regularly

5
Evidence for methadone maintenance therapy
(MMT)Faggiano F, et al (2003)

• Aim to evaluate the efficacy and safety of
  different doses of MMT for opioid dependence, in
  modifying health and social outcomes, and in
  promoting patient's familial, occupational and
  relational functioning
• From 11 randomised clinical trials (RCTs) of
  2,279 people the results showed that
• 60100mg of methadone daily is more effective
  than lower doses at retaining patients in
  treatment
• 60100mg of methadone daily is more effective
  than lower doses at reducing use of heroin or
  cocaine

6
What about buprenorphine vs. placebo?Mattick RP,
et al (2003)

• Aim to evaluate the effects of buprenorphine
  maintenance against placebo and methadone
  maintenance in retaining patients in treatment
  and in suppressing illicit drug use
• 13 RCTs of 2,544 people lasting 652 weeks
• 11 compared buprenorphine with methadone (see
  next slide)
• 2 were placebo-controlled
• buprenorphine was statistically significantly
  superior to placebo in retaining patients in
  treatment at doses of
• 24mg (RR1.24 95 CI 1.061.45)
• 8mg (RR1.21 95 CI 1.021.44)
• 16mg (RR1.52 95 CI 1.231.88)

7
How do methadone and buprenorphine
compare?MaintenanceMattick RP, et al (2003)

• Buprenorphine is less effective than MMT in
  retaining patients in treatment (RR0.82 95 CI
  0.690.96 in flexible dose studies). This was a
  statistically significant result
• Low-dose buprenorphine (24mg) is not superior to
  low dose methadone (2035mg)
• High-dose buprenorphine (612mg) does not retain
  more patients in treatment than low dose
  methadone
• High dose buprenorphine was less effective than
  MMT in suppression of heroin use

8
Advantages disadvantages of buprenorphineRCGP.
Guidance for the Use of Buprenorphine for the
Treatment of Opioid Dependence in Primary Care
(updated 2004)

• Disadvantages
• highly soluble, leading to potential for
  injection (can result in abscesses venous
  thrombosis)
• can precipitate opiate withdrawal if used
  incorrectly
• difficult to initiate in patients on high doses
  of methadone
• less sedating
• more expensive
• may be less effective at retaining people in
  treatment

• Advantages
• less dangerous in overdose
• effects of other opioids used in conjunction are
  markedly reduced
• easier to withdraw from
• less sedating
• easier to transfer to naltrexone treatment after
  withdrawal
• fewer interactions

9
Conclusion

• Maintenance therapy harm reduction is
  preferable for most patients
• 60100mg MMT psychosocial support 1st line
  treatment for opioid dependence
• MMT is effective in retaining people in
  treatment, reducing heroin use and stopping
  people people returning to illicit drug misuse
• Buprenorphine is not as effective as high-dose
  MMT but is an alternative where this cannot be
  administered
• The evidence to support the use of other
  therapies is poor
• Consider withdrawal only when patient is well
  motivated