The Cardiovascular
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Morphine milligram equivalents (MME) per day

Converts total daily opioid doses to oral morphine equivalents.

Morphine milligram equivalents (MME) per day
Morphine (oral)
mg/day
Oxycodone
mg/day
Hydrocodone
mg/day
Hydromorphone (oral)
mg/day
Oxymorphone
mg/day
Codeine
mg/day
Tramadol
mg/day
Tapentadol
mg/day
Fentanyl transdermal
mcg/hr
Methadone
mg/day
Complete the fields above to see the result.

When to use

  • Standardising total opioid exposure to assess overdose risk and guide prescribing thresholds.

Formula

Sum of (daily dose x conversion factor): morphine 1, oxycodone 1.5, hydrocodone 1, hydromorphone 4, oxymorphone 3, codeine 0.15, tramadol 0.1, tapentadol 0.4, fentanyl patch 2.4 (per mcg/hr). Methadone is tiered: 4 (<=20 mg/day), 8 (21-40), 10 (41-60), 12 (>60).

Pearls and pitfalls

  • Conversion factors are for risk assessment, not for directly switching between opioids; reduce by 25-50% and titrate when rotating.
  • Methadone's factor rises with dose because of its long, variable half-life.

References

  1. Dowell D, et al. MMWR Recomm Rep. 2016;65(1):1-49.