Persistent Pain in Secure Environments Health and Justice Pharmacy Network Meeting Tuesday 18 March 2014

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1 Persistent Pain in Secure Environments Health and Justice Pharmacy Network Meeting Tuesday 18 March 2014 Dr Iain Brew Vice Chair RCGP SEG Health & Justice CRG Member

2 Special Considerations General reluctance to opiates and benzo s It s more difficult to obtain illicit drugs in jail High rate of physical illness & injury Increased complications from lifelong conditions Eg painful diabetic neuropathy Pain avoidance / opiate hyperalgesia Immediate gratification / poor long term planning Sense of entitlement with improved healthcare

3 Background to PHE Guidance Initial Meeting at the Frenchay Hospital 9 February 2012 Multiple stakeholders: BPS, RPS RCGP, DH, NTA, HPA etc Throughout 2012: various iterations Emergence of pregabalin / gabapentin as an issue

4 The context: key points (from PHE guidance) The prevalence of long-term pain in secure environments is unknown Prisoners have a number of risk factors for chronic pain, including mental health and substance misuse disorders, physical and emotional trauma It can be difficult to distinguish patients who need medication for pain from those who want to misuse it or trade it as a commodity The secure environment offers an opportunity to assess regularly the effect of analgesic medications on pain and function Professional isolation and fear of criticism and complaints can erode confidence in prescribing decisions.

5 Evidence Base No evidence on prevalence of CNCP Poor evidence for opiates in CNCP Neuropathic pain is difficult to treat Amitriptyline <75mg has best evidence best Rx gives only ⅓ benefit to ⅓ patients

6 Prevalence of CNCP % taking continuous analgesia for CNCP (Dr MD Croft MSc thesis)

7 Prevalence of CNCP % taking continuous opioids for CNCP (Dr MD Croft MSc thesis)

8 That s NICE CG96 & 173

9 That s NICE CG 173 Offer a choice of amitriptyline, duloxetine, gabapentin or pregabalin as initial treatment for neuropathic pain (except trigeminal neuralgia) If the initial treatment is not effective or is not tolerated, offer one of the remaining 3 drugs, and consider switching again if the second and third drugs tried are also not effective or not tolerated. Consider tramadol only if acute rescue therapy is needed

10 Patient statements on pregabalin If you get the dosing right then you only need to be conscious for a few hours every day They are better than crack! I rattled for weeks when you took them off me last time. I really need them I broke my leg 5yrs ago

11 GABA neuromodulator pharmacology Gabapentin: GABA analogue: Like diazepam Poorly understood, but increases GABA and reduces the secretion of excitatory neurotransmitters [by blocking the α2δ subunit of voltage-gated calcium channels in the CNS] Pregabalin: pro-drug of GBP Increased bioavailability after oral dosing vs GBP: bioavailability decreases as dose rises

12 GABA neuromodulators Both potentiate the effects of opioids & hooch Anxiolytic, sedative and relaxant & euphoriant Not routinely screened for Mandatory Drug Testing Easy to get: learned behaviour ( shooting pains, doc ) Easy to get from secondary care & GPs They are requested by name by drug using patients BUT both are associated with deaths in custody

13 HMP Leeds Approach Confirm GP prescription Review evidence for diagnosis of neuropathic pain Wean off 50mg a week PG / 300mg a week GBP Stop if evidence of diversion: consider weekly I/P & audits??? Offer alternatives: amitriptyline, duloxetine, carbamazepine Encourage physical treatments Offer tramadol (once daily supervised) if above measures are ineffective

14 so how does this fit with NICE? Specialist setting with high numbers of drug users Concentrated dealer market Trading is part of prison life Judiciary aware of this! High level of scrutiny after DIC Robust multidisciplinary diagnosis & good documentation Bolam: we all think the same Bolitho: our approach is logical

15 so how does this fit with NICE? Specialist setting with high numbers of drug users Concentrated dealer market Trading is part of prison life Judiciary aware of this! High level of scrutiny after DIC Robust multidisciplinary diagnosis & good documentation Bolam: we all think the same Bolitho: our approach is logical

16 Making the diagnosis robustly Pain is a subjective experience and can only be diagnosed by interpreting the patient s report Good communication with the patient s community healthcare team can help to identify pre-existing painful conditions The onset of pain is often related to an obvious inciting event, such as trauma or other tissue damage Pain is usually associated with an observable (but variable) decrement in physical functioning The history (nerve injury or damage) and any abnormal findings on sensory examination can support the diagnosis of neuropathic pain Understanding the complexity of origin of visceral pain and of poorly defined disorders can help to plan realistic interventions.

17 The Role of Opioids Methadone is suitable for managing persistent pain and its use for this indication is established practice once-daily dosing is unsuitable for managing pain and it should instead be given as a twice-daily divided dose Tramadol has opioid receptor and monoamine effects, and might be useful in some cases before a morphine trial Transdermal fentanyl patches are equivalent to a high daily dose of morphine (see table) and are not indicated for managing pain in this context

18 Opioids for persistent pain: key points The WHO analgesic ladder has poor applicability in treating persistent non-cancer pain Evidence for opioids effectiveness in managing long-term pain is lacking, particularly in relation to important functional outcomes Opioid therapy should support other pain management strategies e.g. physiotherapy If doses of 120mg morphine equivalent/day do not achieve useful relief of symptoms, the drug should be tapered and stopped All opioids (strong and weak) should be prescribed with caution

19 Opioids for persistent pain: key points (2) There is no evidence that any opioid produces superior pain relief to morphine Sustained release opioid preparations can be used for most cases Fast-acting preparations are unsuitable to treat persistent pain Methadone is an established way of treating long-term pain. For patients with pain who also receive methadone substitution, pain can be treated by maintaining an effective daily dose in two divided increments When converting from one opioid to another, ratios should be cautious and the effect monitored. Conversion ratios between opioids vary substantially, particularly for methadone.

20 Non-pharmacological management of pain: key points Fears and mistaken beliefs about the causes and consequences of pain must be addressed Co-morbid depression and other psychological disorders need treating as part of pain management Good evidence supports active physical techniques in managing pain Physical rehabilitation is best combined with cognitive and behavioural interventions Interventions such as TENS and acupuncture are poorly supported by evidence for benefit but may support self-management of pain.

21 SUGGESTED DOSING FOR COMMONLY USED DRUGS IN TREATING NEUROPATHIC PAIN (Start all drugs at a low dose with at least one week between dose increments) DRUG Amitriptyline Nortriptyline Duloxetine Carbamazepine Gabapentin Pregabalin DOSE 10-75mg once daily 10-75mg once daily mg once daily mg daily in two divided doses mg daily in three divided doses mg daily in two divided doses If pregabalin needs to be withdrawn, reduce the daily dose gradually at a maximum of mg/week. Withdraw gabapentin at a maximum rate of 300mg daily dose every four days.

22 Representations to NICE A number of Stakeholders lobbied: RCGP SMAHU RPS & Numerous Individuals contributed NICE concluded that in the absence of hard evidence of pregabalin abuse it was still to be recommended

23 NICE Elephant in the Room There has been some suggestion that some pharmacological agents for neuropathic pain are associated with increased potential for misuse. However, there had not been enough high-quality evidence to adequately explore this issue. Further research should be conducted

24 Discussion