ToolsCalculators
Opiate conversion calculator
Converts a daily opioid dose to an oral morphine milligram equivalent (MME) and to another opioid.
Opiate conversion calculator
Current opioid
Current total daily dose (or patch strength for fentanyl)
mg/day (mcg/hr for patch)
Convert to
Complete the fields above to see the result.
When to use
- Estimating an equianalgesic starting dose when rotating between opioids, and gauging total opioid burden in morphine milligram equivalents.
Formula
MME/day = dose x oral conversion factor (morphine 1, oxycodone 1.5, hydrocodone 1, hydromorphone 4, codeine 0.15, tramadol 0.1, oxymorphone 3, tapentadol 0.4); fentanyl patch MME/day = mcg/hr x 2.4. Converted dose = MME/day / target factor.
Pearls and pitfalls
- Apply a dose reduction (commonly 25-50%) for incomplete cross-tolerance when rotating opioids, then titrate to effect.
- Conversion factors vary between published tables; treat any output as a starting estimate, not a precise equivalence, especially for methadone, which is not included here due to its non-linear, dose-dependent potency.