Methadone conversion from oral morphine
Initial methadone dose range from the FDA label's morphine conversion table.
Inputs
0 of 1mg/day
When to use
- Rotating to methadone, ideally with a pain or palliative specialist.
Pearls and pitfalls
- The conversion ratio rises steeply with dose; a single ratio is dangerous.
- Methadone accumulates for 5 days or more; do not increase sooner than every 5 to 7 days.
- Get an ECG for QTc at baseline and after titration.
- Many experts cap the starting dose (often 30 to 40 mg/day) regardless of prior dose.
Why use
Shows the label's dose-dependent ratio and a conservative starting point.
Initial methadone (mg/day) = oral morphine (mg/day) × label percentage for that dose range