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Opioid MME and rotation

Two calculators for ADULT patients, kept apart on purpose. The daily total scores an opioid burden on one scale. The rotation converts one opioid to another from a different table, with a reduction for incomplete cross tolerance. Choose one below. The guideline that publishes the total's factors states they must not be used to convert one opioid to another.

Choose a calculator
The CDC guideline states that the calculated dose in morphine milligram equivalents must not be used to determine the dose when one opioid is changed to another. Use the rotation calculator for that, which uses a different table and applies a reduction for incomplete cross tolerance.

These factors do not apply to the dosing of medication for opioid use disorder.

Conversion factor table

CDC 2022 Clinical Practice Guideline (Table 1)

Opioid 1

mg/day
Choose an opioid and enter its daily dose. Add a row for each opioid the patient takes. Read the unit beside each dose field, because transdermal fentanyl is dosed in micrograms per hour and every other row is milligrams per day.

Where the two tables disagree

  • Hydromorphone: the CDC 2022 table gives 5, and the VA/DoD table gives 4.

Both figures are published. This calculator averages neither. The total above names the table it came from.

Reference tables

These tables are printed for reading. Neither calculator above computes anything from them, and no figure below is entered for you.

Methadone dose bands, VA/DoD Table D-6

This calculator computes no methadone conversion. The table below is the published band table, and it is here to read.

Methadone conversion is not linear and the ratio to morphine widens as the dose rises. The Faculty of Pain Medicine prints no potency figure for it, and ASRA states there are no easy conversion rates. This calculator shows the published dose band only. A methadone conversion needs a clinician experienced with the drug.

Oral morphine dose bands and the published methadone ratio for each band
Oral morphine, mg/dayRatio of morphine to methadone
0 to 302 to 1
31 to 994 to 1
100 to 2998 to 1
300 to 49912 to 1
500 to 99915 to 1
1000 to 120020 to 1
1201 and aboveThe source says to consult rather than giving a ratio.

The ratio widens as the dose rises. A ratio taken from a low band and applied at a high dose gives a large overdose.

Transdermal fentanyl patch, Faculty of Pain Medicine

Transdermal fentanyl patch rates and the oral morphine dose each rate is given against
Patch, mcg/hrOral morphine, mg/day
1230
2560
50120
75180
100240

Buprenorphine patch, weekly schedule

The weekly schedule and the twice weekly schedule are separate schedules. Their numbers are not interchangeable. Read the schedule name before you read a row.

Weekly buprenorphine patch rates, with the oral morphine and codeine doses the source prints
Patch, mcg/hrOral morphine, mg/dayCodeine, mg/day
512120
1024240
2048

The source prints no codeine figure at 20 micrograms per hour. That cell is empty here for the same reason. The value is not interpolated.

Buprenorphine patch, twice weekly schedule

This is a different schedule from the weekly table above. Do not read a row from one schedule against the other.

Twice weekly buprenorphine patch rates, with the oral morphine dose the source prints
Patch, mcg/hrOral morphine, mg/day
3584
52126
70168

Opioids this calculator refuses

Each drug below is absent from the calculators above on purpose. The reason is printed with it.

  • Buprenorphine

    Refused for the daily total and for a rotation.

    The CDC table excludes buprenorphine, and the VA/DoD guideline states that its work group is unable to give any equianalgesic dosing figure for it. Buprenorphine is a partial agonist with a ceiling effect, so a single factor does not describe it. A conversion needs a clinician experienced in this drug.

  • Meperidine (pethidine)

    Refused for the daily total and for a rotation.

    No table read carries a conversion factor for meperidine.

  • Levorphanol

    Refused for the daily total and for a rotation.

    No table read carries a conversion factor for levorphanol.

  • Pentazocine

    Refused for the daily total and for a rotation.

    No table read carries a conversion factor for pentazocine.

  • Butorphanol

    Refused for the daily total and for a rotation.

    No table read carries a conversion factor for butorphanol.

  • Nalbuphine

    Refused for the daily total and for a rotation.

    No table read carries a conversion factor for nalbuphine.

  • Fentanyl, intravenous or intramuscular

    Refused for the daily total and for a rotation.

    No source read states an equianalgesic dose for parenteral fentanyl. The only fentanyl conversions found are transdermal. Do not scale the transdermal figure to an intravenous dose.

Opioid tolerance, the FDA label definition

The label names these daily doses. It states a minimum duration of 7 days.

The daily doses the FDA label names in its opioid tolerance definition
OpioidDaily dose
Morphine, oral60 mg/day
Fentanyl, transdermal25 mcg/hr
Oxycodone, oral30 mg/day
Hydromorphone, oral8 mg/day
Oxymorphone, oral25 mg/day
Hydrocodone, oral60 mg/day

What these calculators assume

  • Morphine milligram equivalents score a daily burden. The guideline that publishes the factors states they must not be used to convert one opioid to another.
  • The published tables disagree with each other. Hydromorphone is 5.0 in the CDC table and 4 in the VA/DoD table, and tramadol and codeine differ between CDC and the Faculty of Pain Medicine. The source is named on every figure and no figure is averaged.
  • Buprenorphine has no conversion factor in these sources and is refused in both directions.
  • Methadone is not linear. The ratio to morphine widens with the dose, so a band table is shown and no single factor is applied.
  • The 50 morphine milligram equivalents per day figure is the point the CDC 2022 guideline names for additional care. It is a CDC figure whichever conversion table produced the total, and the VA/DoD guideline names a different one. CDC sets no hard ceiling and states there is no single threshold below which risk is removed.
  • These factors do not apply to the dosing of medication for opioid use disorder.

This calculator reports published conversion factors and names the source of each. It does not choose between sources that disagree, it refuses the drugs its sources refuse, and it never returns a rotation dose from the morphine milligram equivalent factors.

Formula

  • MME per day = sum over each opioid of dose x conversion factor
  • Every dose is mg/day except transdermal fentanyl, which is mcg/hr

Source

  • CDC Clinical Practice Guideline for Prescribing Opioids for Pain, MMWR Recomm Rep 2022 (Table 1 conversion factors and its cautions); VA/DoD Clinical Practice Guideline for the Use of Opioids in the Management of Chronic Pain (Table D-3 conversion factors, Table D-6 methadone dose ratios); Faculty of Pain Medicine of the Royal College of Anaesthetists, Opioids Aware (oral potency table and transdermal patch tables); StatPearls Opioid Equivalency, NCBI Bookshelf NBK535402 (the incomplete cross-tolerance reduction bands); FDA labels via DailyMed for the opioid-tolerance definition.

Clinical reference only. Verify independently; clinical judgment governs.