Page 44 - CPG - Clinical Practice Guidelines - Management of Cancer Pain

Management of Cancer Pain (Second Edition)
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Conversion of oral morphine to oral oxycodone
Oral morphine mg/day (20 mg 4-hourly = 120 mg per day)
Conversion factor = divide by 1.5
Equivalent dose of oxycodone = 120 ÷ 1.5 = 80 mg per day
Reduce equivalent dose by 25% = 60 mg per day (due to incomplete
cross-tolerance)
Therefore, dose of CR oxycodone = 30 mg twice daily

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Conversion of oral morphine to transdermal fentanyl
Oral morphine mg/day (16 mg 4-hourly = 100 mg per day)
Conversion factor = divide by 3
Equivalent dose of transdermal fentanyl = 100 ÷ 3 = 33 mcg per hour
Reduce equivalent dose by 25% = 25 mcg per hour (due to incomplete
cross-tolerance)
Therefore, dose of TD fentanyl = 25 mcg per hour

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• Opioid rotation should be considered in patients with cancer pain who
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adverse events.

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Methadone is an alternative treatment in specialist services for special
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syndrome and hyperalgesic states. Its use in cancer pain management
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pharmacology. In Malaysia, methadone is mainly used for harm
reduction in Methadone Replacement Therapy. However, its method of
use is different in treating cancer pain.
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and tolerability of methadone as an analgesic for cancer pain vs active
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{ methadone was similar to morphine in the effectiveness of pain control
{ methadone was well tolerated; however, somnolence was more
common with methadone while dry mouth was more common with
morphine
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very low.

In another systematic review of 10 small studies on cancer pain,
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