Opioid Equivalent Dosing
Substance Route Daily Use Total
Morphine PO mg
Oxycodone (Percocet) PO mg
Hydromorphone (Dilaudid) PO mg
Meperidine (Demerol) PO mg
Hydrocodone (Vicodin/Norco) PO mg
Methadone PO mg
Fentanyl Patch mcg/hr
Morphine IV mg
Hydromorphone (Dilaudid) IV mg
Meperidine (Demerol) IV mg
Fentanyl IV mcg
General approach to dosing an oral opioid regimen: Provide 100% of expected MED (morphine equivalents) in long acting form, as well as ~15% PRN option for breakthrough pain with dosing interval comparable to medication half life (q3-4h for oral meds), and retitrate daily. Note that if changing agents, should decrease estimated dosing 25-50% given variable cross-tolerance to different agents. (Dosing values should be rounded to nearest formulation doses)
Methadone (dose BID or TID)
Sliding Scale Conversion Ratios
Morphine (PO mg) Morphine : Methadone
<30 2:1
<100 4:1
<300 8:1
<500 12:1
<1000 15:1
>1000 20:1
Caution: Methadone is a potent medication with unreliable conversions.
Generally safer to just start at a low dose and slowly titrate up every 3 days
Fentanyl Parenteral (Patch)
Sliding Scale Conversion
Fentanyl (mcg/hr x 24hr) Morphine (PO mg)
25 50
75 250
100 350

Opioid Equivalence Table Reference