FACTSHEET 6 ON PALLIATIVE CARE PRINCIPLES OF PAIN CONTROL 1: OPIOID ANALGESICS

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1 FACTSHEET 6 ON PALLIATIVE CARE PRINCIPLES OF PAIN CONTROL 1: OPIOID ANALGESICS Pain remains the most feared symptom among cancer patients. Many patients with non-malignant, life-threatening disease also suffer pain. Many patients will have more than one type of pain - each pain should be assessed separately. Active involvement of both patient and family in treatment decisions will improve pain management. A multidisciplinary approach has been shown to provide better symptom control for patients with advanced disease. Assessment of Pain Pain is not purely physical, consider: psychological social cultural financial spiritual aspects History Note aggravating and/or relieving factors especially effect of treatments already tried. Note impact on patient, meaning of pain to the patient, how pain varies with mood etc. Examination and Documentation If helpful ask the patient/carer to keep a record of pain score throughout the day. Pain may improve as a result of treatment, or change as a result of progression of disease, therefore accurate records required. Diagnosis Investigations should be tailored to the physical and psychological condition of patient. Aim to identify type of pain e.g. abdominal colic, nerve pain, bone pain, and consider using pain chart to record different areas of pain. (NB pain may not necessarily be due to the primary disease) Explanation to the Patient Include identifying with the patient realistic goals and limitations of treatment. Treatment Analgesic medication including adjuvant medication (refer to Factsheet 7) as appropriate. Consider need for additional non-pharmacological measures (refer to Factsheet 7) Page 1 of 6 Factsheet 6

2 Re-assess Regular monitoring of the response of pain to planned treatment. Pain may need to be monitored several times per hour in an acute situation - but on weekly/fortnightly basis in a more stable situation. WHO ANALGESIC LADDER FOR CONTROL OF PAIN The WHO principles of cancer pain management are: by the mouth - oral medication if possible by the clock - regularly NOT prn by the ladder - increasing potency of analgesia for increasing severity of pain LEVEL 3: opioid +/- non-opioid +/- adjuvant* LEVEL 2: Weak opioid + non-opioid +/- adjuvant* PAIN PERSISTING OR INCREASING LEVEL 1: Non-opioid +/- adjuvant* PERSISTANT OR INCREASING PAIN PAIN * ADJUVANT ANALGESIA - Refer to Factsheet 7 Use drugs you know well e.g. paracetamol codeine morphine GENERAL RULES At each level on the ladder: if pain is not responding to the maximum dose of prescribed analgesic, given regularly, move up. If pain partially responding check dose/timing of medication and possible role for adjuvant analgesic. Page 2 of 6 Factsheet 6

3 LEVEL 1: Mild Pain - Non-opioid Preferably paracetamol - BNF recommended maximum 4g in 24 hours Available as tablets, elixir, and suppository NB paracetamol is not contra-indicated in cancer patients with secondary disease in the liver, but dose will need to be reduced in patients below 40kg, or with documented hepatic impairment. LEVEL 2: Moderate Pain - Weak opioid Codeine phosphate Dihydrocodeine tartrate Codeine or dihydrocodeine maximum (ceiling dose) = 240mg in 24 hours. LEVEL 3: Severe Pain - Strong opioid Strong opioid of choice remains morphine - many formulations - no maximum dose As per NICE guidance* STARTING ORAL MORPHINE Discuss with patient to allay fears and misconceptions Not addictive when dose titrated against pain Tolerance not a problem (over weeks/months) when used orally for pain (more pain indicates probable increase in disease burden therefore increased analgesia required) Offer written information Side effects Constipation will always occur in patients with normal functioning bowels - ALWAYS prescribe laxative concurrently (refer to Factsheet 12). Drowsiness at start/on increment usually resolves within 48 to 72 hours Nausea may occur - usually resolves over three to four days (prescribe prn anti-emetic refer to Factsheet 10) may recur on increasing morphine dose. Other side-effects e.g. confusion, myoclonus, hallucination, itch, bronchospasm. May require reduction in morphine dose or alternative strong opioid SEEK SPECIALIST ADVICE Page 3 of 6 Factsheet 6

4 Starting dose PRESCRIBING AND TITRATING Usually 5 to 10mg of immediate release morphine i.e. morphine sulphate solution (e.g. Oramorph) or standard morphine tablets (e.g. Sevredol) Check recent weak opioid requirement (refer to Factsheet 4) for equivalents. 2.5 to 5mg for elderly patients Patients with severely impaired renal and/or liver function should be prescribed 2.5 to 5mg, or suitable alternative e.g. oxycodone Dosing frequency 4 hourly less frequently in renal or liver impairment and in elderly determine the frequency by duration of analgesic effect (prescribe 6 8 hourly as required) Dose increase Usually allow 24 hours before considering dose increase or conversion to slow release formulation to allow time to steady state (up to three to four days in renal/liver impairment and elderly) Increase by 50% at lower dose range e.g mg, 33% at higher dose range e.g mg Breakthrough dose (to be prescribed in addition to regular dose) For pain occurring before the next regular dose of analgesia is due or unpredictably at any time. ALWAYS prescribe as required (prn) dose equivalent to 4 hourly dose and give if pain occurs. Patients who have been titrated to a regular daily dose will still need breakthrough medication available as a pain exacerbation may occur unexpectedly. CONVERSION TO MODIFIED RELEASE FORMULATION If pain is controlled with regular and breakthrough doses: combine the total 24hr morphine dose and convert to modified release (and recalculate breakthrough dose). Page 4 of 6 Factsheet 6

5 If pain incompletely controlled continue titration incorporating breakthrough doses into regular dose and ensuring increased prn dose prescribed. Once total 24 hour dose requirement has been determined i.e. pain controlled with regular and breakthrough doses: combine the total 24hour morphine dose and convert to modified release formulation e.g. modified release morphine 12 hourly. Regular + breakthrough = total 24hr dose:- divide by 2 to give twelve hourly dose = modified release morphine dose e.g. A patient taking 20mg immediate release morphine 4hourly requiring two 20mg breakthrough doses over 24 hours can be converted as follows 20mg immediate release morphine 4hourly = 6 x 20mg = 120mg in 24 hours plus 2 x 20mg breakthrough doses = 2 x 20mg = 40mg in 24 hours total 24hrs dose =160mg divide by 2 for modified release morphine dose Prescribe modified release morphine 80mg bd (12 hourly regularly) Prescribe increased breakthrough dose (160 : 6) prn 20 to 30mg 4 hourly. Give first modified release morphine dose with last 4 hourly dose to cover change. Be aware of changing needs and the possibility of decreasing doses, where analgesic requirement reduces following e.g. a deterioration in a patient s condition or response to other treatment e.g. radiotherapy. Dose-end pain if a patient on a modified release (12 hour) formulation is regularly needing breakthrough medication a few hours before the next regular 12 hour dose, this is an indication to increase the dose (by the total breakthrough amount) NOT to increase the frequency. (It is very rare that patients require 12 hourly medication at intervals less than 12 hours recommended to discuss with a specialist if being considered.) SIGNS AND SYMPTOMS OF EXCESS OPIOID/OVERDOSE Persistent excessive drowsiness Pinpoint pupils Myoclonic jerks (twitching) Respiratory depression STOP regular opioid medication, reassess requirement, patient will need breakthrough dose (consider reducing dose) 4 hourly as required to control pain. Page 5 of 6 Factsheet 6

6 CHECK has analgesic requirement reduced e.g. pain responded to radiotherapy has accumulation of opioid occurred due to deteriorating renal and/or liver function has excess opioid been used in an attempt to treat pain which is not fully opioid responsive? NB: Opioid reversal is very rarely required in palliative patients receiving opioid analgesia. However, ensure that naloxone injection is available in all clinical locations in accordance with NPSA safer practice notice May INCIDENT PAIN Incident pain is predictable pain occurring with movement, weight bearing, dressing change or other incident. Patients are often pain free at rest. Explain cause of pain to patient and negotiate treatment Avoid increasing regular opioid dose Exclude surgically correctable problems such as impending or actual bone fracture Possible treatments include short acting fentanyl formulations buccal/sublingual/intra-nasal (will need discussion with specialists) Trial breakthrough dose of morphine (i.e. 1/6 th of 24hr analgesic requirement) 30 minutes before the incident which produces pain Patient self-administration of nitrous oxide/oxygen (Entonox) mixture at time of incident Consider non-pharmacological therapies - e.g. preventing movement by using mechanical aids, reducing pain by anticipatory use of TENS. Refer for specialist advice if pain control not attained with the above measures. For alternative routes of administration Refer to Factsheets 1 and 2 (subcutaneous delivery), Factsheet 5 (Transdermal). General palliative care references include: Palliative Care Formulary, Fourth Edition (PCF4) Edits: Robert Twycross and Andrew Wilcock available via Palliativedrugs.com Palliative Adult Network Guidelines Third Edition (also available as an App) Edits: Max Watson, Caroline Lucas, Andrew Hoy, Ian Back, Peter Armstrong Take note of: NPSA Rapid Response Report NPSA/2008/RRR05 Reducing Dosing Errors with Opioid Medicines 4 th July 2008 *NICE (National Institute for Health and Clinical Excellence) clinical guideline 140: Opioids in palliative care: safe and effective prescribing of strong opioids for pain in palliative care of adults May 2012 Page 6 of 6 Factsheet 6