Transcript Opioids in chronic, non-cancer pain

Dr Angus Robin
Bradford VTS Feb 18th 2014
(with some slides from Dr Tim Williams and Dr F Cole)
WHO pain ladder
 Was designed for cancer pain.
 Methadone was initially planned, morphine in the
end....
 Gives us ‘permission’ to escalate doses v quickly – or so
it seems.
 Doesn’t remind us about topical things or neuropathic
agents.
“But the drugs don’t work Dr...”
 Expect analgesic failure; pursue analgesic success
(BMJ 8th June 2013, page 19-21)
 Most analgesics don’t work for most people, when
you define ‘work’ as a 50% reduction (NNT...)
 Most studies in acute post-op pain...so useless in
the vast majority of patients.
 Very few studies beyond 12 weeks.
PHN Medications: NNT, NNH
Drug
NNT
NNH minor
NNH major
TCA
2.6
5.7
16.9
Gabapentin
4.4
4.1
12.3
Pregabalin
4.9
4.3
Opioids
2.7
3.6
6.3
Tramadol
4.8
7.2
10.8
NNT number needed to treat, NNH number needed to harm
Wu CL, Raja SN. J Pain 2008
 In low back pain tapentadol has a 90% failure
rate (to give 50% relief) and oxycodone has a
100% failure rate.
 This is consistent with observations of other
opioids and what we see in the pain rehab
‘living with pain’ team.
 When they do work they improve sleep, mood, fatigue,
QoL, etc (unsurprisingly).
 If one drug in a class fails, others may not, so we don’t
know the best order to try drugs which mainly fail.
 Due to low success rates, is polypharmacy the answer?
(can of worms time....serotonin syndrome, etc).
 A 50% pain reduction in a small group of patients is
worth seeking out....
 Expect modest benefits and frame patient expectations
of analgesia benefits more realistically
 Mention relaxation therapies as useful tools in
setbacks / flare-ups
 All the meds can help, but nowhere near as much as
pharma wants us to think
Before you start opioids
 Be aware safety and efficacy of long term opiates is
uncertain.
 Be aware of BPS guidance.
 Do a comprehensive Pain assessment
Including ……. The meds they’ve tried (and how
long for – actually go through the records)
Co-morbid conditions
GOALS and WIDER PLAN
There is no evidence from RCTs to
support that benefits of long term
opioid therapy outweigh the risks.
Starting Opioids
 Discuss well established side effects
 Appropriate preparation
Long-acting
Dose
Never injectable (rarely short-act)
 Start low and go slow (<120mg/day)
 Co prescribe anti-emetic + laxative
 Agree follow up interval (1-2 weeks, then monthly)
 Same prescriber ideally
 Consider a contract
Opiate Adverse Effects
 80% will experience side effects
constipation
nausea/vomiting
itch
dizziness
sedation (driving?) ...anecdote re: bus driver
 Long term immunological/endocrine effect
 Addiction, dependence. “Using for sleep Dr”
 Withdrawal (sweat/cramps/yawn/tremor)
 Opioid induced hyperalgesia is rare, but real.
Hormonal disturbance
 GnRH reduced and subsequent effects on FSH/LH
levels.
 Leads to androgen/oestrogen level changes.
 Prolactin possibly increased.
 TFTs seem unaffected.
 Worsens diabetes, worsens obesity (multifactoral).
Mortality data
 In the US opioid related deaths rose from 4041 in 1999
to 14459 in 2007.
 This is more than road traffic accidents.
 In the UK deaths from prescribed opioids roughly
doubled between 2005-09.
Approximate equivalent doses
N.B. There is no
universal agreement
24 hour dose Morphine
equivalent per day
Codeine
240 mg
40mg (26 – 60)
Dihydrocodeine
240 mg
50mg
Tramadol
400 mg
Up to 120mg
Oxycodone
20mg
40mg
Dose Equivalents
Oral Morphine 10
(mg/24hrs)
15
30 45
60 90
120 180
Transdermal
5
Buprenorphine
(µg/hr)
10
20
35 52.5
70
Transdermal
Fentanyl
(µg/hr)
12
25
50
270
75
Managing established patients
 Regular review (monthly/6monthly)
to include…..
effectiveness
side effects
plan compliance
progression to goals
clear documentation
 Alternatives for ‘flare-up’ management. Ideally this is
where ‘compassion days’ come in....pacing skills.
Flare-Up Management
 Establish ‘flare-up’ and not new pain
 Re-assurance that will settle
 Consider short- term changes to other analgesics or
use of alternatives E.g. TNS, relaxation techniques,
pacing activities, self-compassion!(DWP not keen on
this)
 Avoid dose escalation....A&E struggle with this.
Stopping Opiates – When and How
 When?
Patient’s pain and function not
improved, or is worse.
Concerns over addictive behaviour.
Unacceptable adverse effects.
Patient preference.
 How?
Slow/gradual dose reduction
Consider other pain relieving strategies.
The future of opioid
management (is it nearly now?)
So what about GP now?
 Tramadol KPPI in Bradford and Airedale
Tramadol is an opioid analgesic indicated for moderate to
severe pain. Tramadol is a potent drug; at 200mg/day it is
equivalent to 40mg of oral morphine in 24hrs.
Tramadol is available as 12-hourly and 24-hourly modified
release preparations. These preparations are significantly
more expensive than the immediate release formulations and
restrict the up or down titration of the analgesic
according to the patient’s symptoms.
All patients who are prescribed analgesics should have
their pain symptoms and treatment reassessed on a regular
basis.
Summary
 We need patients to know that the medicines will
probably help less than we thought.
 We need to give them more information and review
pain medicines better.
 We need to believe that other methods of dealing with
chronic pain help and take the time to encourage a
patients to engage with this.
BPS guidance
 Summary page:
http://www.britishpainsociety.org/book_opioids_recommendations.pd
f
 Patients version:
http://www.britishpainsociety.org/book_opioid_patient.pdf