Examples of approximate equivalent doses when changing from morphine to another opioid (Table 10.7)

Examples of approximate equivalent doses when changing from morphine to another opioid (Table 10.7) 

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CHANGING FROM CHANGING TO	morphine oral 30 mg 4-hourly	morphine oral CR or SR 60 mg/day	morphine SC 10 mg 4-hourly	morphine CSCI 100 mg/day
fentanyl transdermal	50 micrograms/hour	25 micrograms/hour	50 micrograms/hour	75 micrograms/hour
hydromorphone oral	6 mg 4-hourly	2 mg 4-hourly	6 mg 4-hourly	10 mg 4-hourly
hydromorphone SC	1.5–2 mg 4-hourly	0.5 mg 4-hourly	1.5–2 mg 4-hourly	3 mg 4-hourly
methadone oral	[NB2] [NB3]	[NB2] [NB3]	[NB2] [NB3]	[NB2] [NB3]
morphine SC	10 mg 4-hourly	3 mg 4-hourly	10 mg 4-hourly	16 mg 4-hourly
morphine CSCI	60 mg/day	20 mg/day	60 mg/day	100 mg/day
morphine intrathecal [NB3]	600 micrograms/day	200 micrograms/day	600 micrograms/day	1 mg/day
morphine intracerebro-ventricular [NB3]	60 micrograms/day	20 micrograms/day	60 micrograms/day	100 micrograms/day
oxycodone oral	15 mg 4-hourly	5 mg 4-hourly	15 mg 4-hourly	25 mg 4-hourly
oxycodone oral CR	40 mg twice daily	20 mg twice daily	40 mg twice daily	80 mg twice daily
CR = controlled-release preparation; CSCI = continuous subcutaneous infusion; SC = subcutaneous; SR = sustained-release preparation NB1: these are average equivalents because of pharmacokinetic variation between individuals; doses are approximate because of the strengths of preparations available NB2: care needs to be taken with methadone to avoid toxicity because the time to reach steady-state concentrations following a change in dosage may be up to 12 days. Dose conversion ratios from other opioids are not static, but are a function of previous opioid exposure. Published tables of equianalgesic doses of opioids, established in healthy opioid-naive individuals, indicate that methadone is 1 to 2 times as potent as morphine in single-dose studies, but in individuals on long-term morphine, methadone is closer to 10 times as potent as morphine NB3: consultation with a pain clinic or a palliative care service is advised