The Use of Transdermal Opioids in Palliative Care. G. Whyte, P.Powell, C. Littlewood, A. Coackley, G. Leng External Reviewer/Expert : S.

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The Use of Transdermal Opioids in Palliative Care G. Whyte, P.Powell, C. Littlewood, A. Coackley, G. Leng External Reviewer/Expert : S. Simpson 1

Introduction Dr Graham Whyte Literature Review Dr Paula Powell Guidelines and Standards - Dr Clare Littlewood Discussion 2

Introduction New long term audit No previous guidelines Anecdotal stories of incorrect usage/ adverse effects Uncertainty for generalists Link with Chapter 19: Guidelines for the use of Transdermal Fentanyl in the Dying Patients?amalgamate at later date 3

Transdermal Opioids Literature Review

Morphine is Gold Standard Opioid for Cancer Pain Hanks GW, Conno F, Cherny N, Kalso E, McQuay HJ et al. EAPC Recommendations. Br J Cancer 2001: 84(5):587-593 5

Transdermal Opioids How Do we view them? Niche market?- good in renal failure Stable pain? Oral route not possible? Other opioid toxicity? Compliance issues? Patient preference?? 6

Transdermal Opioids Are they safe and efficacious? For whom and how should they be prescribed? How should conversions to and from other opioids be managed? What knowledge do generalists have of Transdermals? 7

Prescribing Data and Guidelines Palliative Care Formulary 3 rd Edition (PCF3)- Twycross R, Wilcock A, Editors 8

Buprenorphine Love it or hate it? 9

Buprenorphine - Pharmacology Partial µ- opioid receptor agonist. Κ and δ opioid receptor antagonist. Physiological effects similar to morphine. Metabolised via the liver and inactive metabolites are excreted via faeces. Twycross R, Wilcock A (eds). Palliative care formulary. 3rd edition. pp 289-306 10

Side Effects-Common >10% Dizziness Drowsiness Headache Nausea and vomiting Local irritation 11

Side Effects-Uncommon <10% Anxiety Insomnia Asthenia Hypotension Fainting Oedema Anorexia 12

Buprenorphine Caution is suggested in patients with severe hepatic dysfunction but not mildmoderate. CYP3A4 inhibitors may increase Levels. Safe in renal failure- not removed by haemodialysis. Slows intestinal transit- constipation less than with morphine. Twycross R, Wilcock A (eds). Palliative care formulary. 3rd edition. pp289-306 13

Buprenorphine Indications- moderate to severe cancer pain not responding to non-opioid analgesics. Intolerance to other opioids Contra-indications- TD route should not be used for acute (transient, intermittent or short term pain) or for rapid dose titration for severe uncontrolled pain. Twycross R, Wilcock A (eds). Palliative care formulary. 3rd edition. pp289-306 14

Buprenorphine Butrans = 7 day patch 5mcg 10mcg 20mcg/hr Transtec = 96 hour patch 35mcg, 52.5mcg, 70mcg/hr. Absorption increased by heat. Buprenorphine equianalgesia with PO morphine varies in literature from 75:1 to 115:1 15

Morphine Equivalents Transtec TTD oral morphine Butrans - - - - 10-20mg 5mcg - - - - 40-60mg 20mcg 35mcg 60-100mg - - - - 70mcg 120-200mg - - - - 140mcg 240-380mg - - - - Merseyside and Cheshire Palliative Care Network audit Group Standards and Guidelines 4 th Ed. 2010 PCF3 recommends 100:1 conversion 16

Commencing Patches - Weekly or 96 Hourly Systemic analgesic concentrations reached within 12-24 hours. Levels continue to rise for 32-54 hours. Steady state may not be reached for 9 days for higher doses. If satisfactory analgesia not achieved after 72 hours then next patch strength should be used. 17

Buprenorphine - Breakthrough Morphine and other µ - opioid receptor agonists are acceptable for breakthrough. Without loss of analgesia. Antagonism does not occur at normal clinical doses. Twycross R, Wilcock A (eds). Palliative care formulary. 3rd edition. pp289-306 18

Breakthrough Analgesia 1/6 th equivalent TDD oral morphine as NR formulation or other opioid in appropriate dose. Sublingual buprenorphine starting dose = 200mcg = 15mg morphine. Longer acting than morphine. Repeat 6-8 hourly. 19

Buprenorphine-Respiratory Depression Rare in recommended doses. Ceiling effect for respiratory depression. Naloxone is required in higher doses (up to 50%) to reverse effects because of strong receptor affinity. Bolus Naloxone may not reverse respiratory depression. (Level 3). Daha A. Palliative Medicine 2006; 20:s3-s8 20

Is Buprenorphine Safe and Efficacious for Patients with Cancer Pain? Review of evidence - Transdermal buprenorphine has superior safety in respect to respiratory depression, immunological and renal effects over other step III opioids. (level 2+) RCT buprenorphine/placebo patches 289 patients. Poulain et al. (level 2+) Sittl R. Transdermal buprenorphine in cancer pain and palliative care. Palliative Medicine 2006;20:25-30 Poulain et al. Journal of Pain and Symptom Management 2008; 36: No 2. 21

Is Buprenorphine Efficacious? Multicentre, open label, uncontrolled, prospective, observational study. 1223 patients recruited non cancer and cancer pain. Dose range 35-70mcg. 1 st line step III opioid. Significant increase in number reporting good or very good pain relief from baseline. 44% drop out. (level 2+) Muriel C et al Clinical theraputics 2005;27(4) 451-462 22

Fentanyl μ-opioid receptor agonist. Lipophylic Metabolised in the liver to norfentanylsafe in renal failure. Caution with CYP3A4 inhibitors/inducers. Action supraspinally- minimal distribution in vascular system (unlike morphine). 23

Sedation Fentanyl Side Effects Nausea and vomiting Constipation Delirium Dry Mouth Neurotoxic effects e.g. Myoclonus, hallucinations. Respiratory depression 24

Transdermal Fentanyl Indications- moderate - severe chronic pain including cancer and AIDS related pain. Severe chronic pain (BNF). Contraindications- nil absolute but should not be used for acute (transient, intermittent or short term pain). British National Formulary March 2010 Twycross R, Wilcock A (eds). Palliative care formulary. 3rd edition. pp289-306 25

Fentanyl in Palliative Care Strong opioid, WHO analgesic ladder step III. Use when step II fails. Stable severe pain, swallowing difficulties, intractable nausea or vomiting. Renal failure egfr < 30. SIGN Guidelines 106 - Control of Pain in Adults with Cancer 26

Transdermal Fentanyl Available as reservoir and matrix patches 12,25,50,75,100micrograms/hr Reservoir- generic products, Tilofyl. Release controlled by rate limiting membrane. Matrix- Durogesic, DTrans and Matrifen. Drug held in an adhesive matrix. Patches are bio-equivalent. Absorption can be increased by heat. Good practice to prescribe by brand. 27

Fentanyl Pharmacokinetics Onset of action 3-23h Time to peak plasma concentration 24-72 hours Plasma half life 13-22h Duration of action 72 hours (48 in some) 28

Equianalgesia with Morphine TDD oral morphine Transdermal Fentanyl 72 hourly 30mg 60mg 120mg 180mg 240mg 720mg 12mcg 25mcg 50mcg 75mcg 100mcg 300mcg Merseyside and Cheshire Palliative Care Network Group Equianalgesic Table 29

Breakthrough Analgesia Prescribe 1/6 th of the equivalent oral TDD morphine or other opioid. Immediate release formulations of Fentanyl e.g. Abstral must be titrated. 30

Is Transdermal Fentanyl Safe and Efficacious? Systematic review of literature 1966-2007. 3RCTs comparing TD Fentanyl with oral morphine. No difference in overall adverse effect profile, or efficacy. Reduction in constipation. Patient preference in favour of Fentanyl. (level 1+) Tassinari D et al. Journal of Palliative Medicine 2008; Vol 11: no 3. 31

Fentanyl Comparison with Morphine Randomised, open, crossover study with morphine. Equally efficacious Fentanyl caused significantly less constipation and daytime drowsiness. (level 2+) Ahmedzai S, Brooks D. J Pain symptom management 1997;13:254-261 32

Fentanyl Morphine-Methadone 3 year RCT 108 patients with advanced cancer. Randomised to receive Fentanyl, morphine or methadone when weak opioids had failed. No difference in pain intensity, QOL, use of additional analgesia, Fentanyl most expensive. Mercadante et al European Journal of Pain 2008; 12: 1040-1046 33

Transdermal Fentanyl - Concerns Informed prescribing is essential. 3 case reports of inappropriate prescribing of Transdermal Fentanyl by clinicians. 84 year woman commenced on 50mcg patch from paracetamol/codeine. (level 3) Ross and Quigley. European Journal of Pain 2003; 7: p481-483 34

Transdermal Fentanyl - Concerns Research showing that Transdermal Fentanyl is safe has usually been conducted by pain specialists. Education is critical to ensure that Transdermal Fentanyl is prescribed appropriately and safely. All doctors should only use drugs with which they are familiar. 35

National Safety Alerts- FDA 2005 Series of significant adverse events (toxic SE and deaths) in USA relating to Transdermal Fentanyl. 36

Conclusions of Investigation into Deaths Lack of appreciation that Fentanyl is a strong opioid. Inappropriate use for acute pain. Lack of patient awareness of safe use, avoid heat sources, signs of overdose. Lack of awareness of potential drug interactions. 37

FDA Update 2007 Transdermal Fentanyl should not be initiated in opioid naive patients. Patients should have received strong opioids to the equivalent of 60mg TDD oral morphine for > 1 week. Must not be initiated for titration. 38

UK Alerts National Patient Safety Agency. Rapid Response Alert June 2008. Adverse events secondary to all opioids. Medicines and Healthcare products Regulatory Agency MHRA- Fentanyl Patches September 2008 39

Factors Identified Dosing errors by healthcare professionals, patients or care givers. Accidental exposure. Exposure to heat resulting in increased absorption. Inappropriate prescribing in opioidnaive patients. 40

Generalists Knowledge Survey questionnaire to GPs, hospital consultants and oncologists. Assessed knowledge of the use of Transdermal Fentanyl in clinical practice. Overall knowledge and confidence in using Transdermal Fentanyl was poor. Welsh J, Reid A, Graham J, Curto J, Macleod K, O Neill C. Pall Med 2005;19:9-16 41

Summary Transdermal opioids are a useful addition to the armamentarium of analgesics. They are effective in controlling moderate to severe pain. They are acceptable to patients and in controlled studies had no more side effects than other opioids. 42

Summary There is evidence from prescribing surveillance that incorrect use of Fentanyl can cause harm to patients. There is some evidence from case reports that inappropriate prescribing can cause harm to patients. There is some evidence that generalists have poor knowledge of the prescribing of Fentanyl 43

General Principles All patients prescribed Transdermal opioids should have a pain assessment in accordance with accepted principles of pain management(1) Patients should be given information regarding their strong opioid and the known side effects(2,14,15) It is good practice to brand when prescribing Transdermal opioids eg Butrans, Durogesic-D trans(19)

Reservoir patches should not be cut due to rapid release of opioid. Matrix patches can be cut although not recommended by manufacturers(5) Patients may experience opioid withdrawal symptoms(gastric flu) when changed from another opioid to Transdermal (3,4)

Guidelines Transdermal opioids are contra-indicated in patients with acute pain and in those who need rapid dose titration for severe uncontrolled pain(1,8)[ Level 3] Patients not previously receiving opioids should start on lowest buprenorphine patch or patients with unrelieved pain despite maximum step 2 analgesic should start on 25 or 35mcg/hr. For Fentanyl patients on maximum step 2 opioids should start on 12mcg/h(5)[Level 3] 46

Systemic analgesic concentrations are generally reached within 12 hrs; so when converting from 4hrly PO morphine give 4hrly doses of morphine for first 12 hrs after applying patch. 12hr mr morphine apply patch and final dose at same time. 24hr mr apply 12 hrs after final dose CSCI continue syringe driver for 12 hrs after applying patch(5) [Level 3] Appropriate breakthrough medication dose should be decided using equi-analgesic tables. Steady state concentrations not reached until 36-48hrs after first application so patient should use liberal p.r.n doses during first 24 hrs See table1(1,5) [Level 3]

Table 1 PO morphine 4 hrly Bu trans weekly Transtec 96 hrly 2-5 mg 5-10mcg - - Fentanyl 72 hrly 5-10 mg 20mcg - 12mcg 10-15mg - 35 mcg 25mcg 15-25mg - 52.5mcg 50mcg 20-30mg - 70mcg 75mcg 40mg - 140 mcg 100mcg

For patients taking morphine that is not dose equivalent it is appropriate to opt for patch that is slightly more or less depending on whether patient is pain free or still in pain(5) [Level 4] When switching opioids due to toxicity consider dose reduction of 25-50%(9,10,11) [ Level 3]

After 72 hrs if patient needs 2 or more doses analgesic/ day next strength patch should be used(5)[ Level4) Up to 25% patients using Fentanyl may need patch change every 48 hrs(12)( Level 4) In dying patients Transdermal patch should remain in place and appropriate as required doses of immediate release opioid prescribed(6)[level 4] Please see guidelines for use of drugs in last hours of life for further information

Transdermal opioids are less constipating than morphine; halve the dose of laxative when starting and titrate according to need(5) Transdermal opioids cause less nausea and vomiting than morphine but if necessary, prescribe haloperidol 1.5mg stat and on for one week then p.r.n[level4]

In febrile patients the rate of absorption of Transdermal opioids increases and can cause toxicity. Absorption may be also enhanced by external heat sources. Patients should be warned about this. They may shower but should not soak in hot bath(5)[level4]

Questions What do we mean by toxicity? How should we manage toxicity due to use of a Transdermal patch? Reduce by 25% 50%? Remove patch? Rotate opioid? Which opioid should we recommend for breakthrough? Pain.

Questions What is the role of Butrans in cancer pain? What information should be given to patients about Transdermal opioids. 54

Standards All patients prescribed Transdermal opioid should have reason documented in notes(13) [Grade D] Transdermal opioids should not be used for acute pain and those who need rapid dose titration(1,8) [Grade C]

Conversion from oral opioids should be used with reference to equianalgesic tables(1,5) [ Grade D] All patients with Transdermal opioids should have appropriate breakthrough analgesia prescribed(1,5) [ Grade D]

References 1. Hanks GW, Conno F, Cherny N, Kalso E, McQuay HJ et al. Expert working group of Research network of European Association Palliative Care. Morphine and alternative opioids in cancer pain: the EAPC recommendations. Br J Cancer 2001: 84(5):587-593 2. SIGN Guideline no 106: Control of pain in adults with cancer. 3. LenzM,DonnerB. Withdrawal symptoms during therapy with Transdermal Fentanyl. Journal of pain symptom management 1994:9:54-5 4. Davis MP. Buprenorphine in cancer pain. Supportive care in cancer 2005;13:878-889 5. Twycross R, Wilcock A (eds). Palliative care formulary. 3 rd edition. Nottingham palliative drugs. Com Ltd.p289-306 6. EllershawJ, KinderC, Aldridge J, Allison M, Smith J. Care of dying: is pain control compromised or enhanced by continuation of Fentanyl Transdermal patch in dying phase? J pain symptom management 2002;24(4):398-403

References 7. Ahmedzais,Brooks D. Transdermal Fentanyl versus sustained release oral morphine in cancer pain: preference, efficacy and quality of life. J Pain symptom management 1997;13:254-261 8. Quigley C. Opioid switching to improve pain relief and drug tolerability. The Cochrane database of systematic reviews 2004(3) Art no:cd004847.doi:10.102/14651858cd 004847 9. Cherny N, RipamontiC, Pereria J, Davis C, Fallon M, McQuay H et al. Strayegies to manage adverse effects of oral morphine: an evidence based report. J clin oncol 2001;9(9):2542-4 10. Indelicato R, Portenoy R. Opioid rotation in management of refractory cancer pain. J Clin Oncol 2002;20(1) 348-352 11. Fallom M, O Neill B. substitution of another opioid for morphine. Opioid toxicity should be manged initially by decreasing opioid dose. Br Med J 1998;316:702-3

References 12. Donner B. Long term treatment of cancer pain with Transdermal Fentanyl. J pain symptom management 1998;15:168-175 13. Mersyside and Cheshire Palliative Care Network Audit Group. Strong opioid substitution. Expert consensus. July 2010 14. USA Food and drug Agency: Safety warning on Fentanyl skin patches 2007 15. Medicines and Healthcare products regulatory agency MHRA. Drug safety Update: Vol 2 Issue2 September 2008 16. Sittl R. Transdermal buprenorphine in cancer pain and palliative care Opioids in palliative care: differentiation and clinical relevance. Palliative Medicine 2006;20:25-30 17. MurielC, FalideI, MicoJ, Niera M, sanchez-magroi. Effectiveness and tolerability of buprenorphine Transdermal system in patients with moderate to severe chronic pain. Clinical theraputics 2005;27(4) 451-462 18. Welsh J, Reid A, Graham J, Curto J, Macleod K, O Neill C. physicians knowledge Transdermal fentany;. Pal Med 2005;19:9-16