Abbreviations: mcg/hr = microgram per hour; mg = milligram; MME = morphine milligram equivalent.
* Multiply the dose for each opioid by the conversion factor to determine the dose in MMEs. For example, tablets containing hydrocodone 5 mg and acetaminophen 325 mg taken four times a day would contain a total of 20 mg of hydrocodone daily, equivalent to 20 MME daily; extended-release tablets containing oxycodone 10 mg and taken twice a day would contain a total of 20 mg of oxycodone daily, equivalent to 30 MME daily. The following cautions should be noted: 1) All doses are in mg/day except for fentanyl, which is mcg/hr. 2) Equianalgesic dose conversions are only estimates and cannot account for individual variability in genetics and pharmacokinetics. 3) Do not use the calculated dose in MMEs to determine the doses to use when converting one opioid to another; when converting opioids, the new opioid is typically dosed at a substantially lower dose than the calculated MME dose to avoid overdose because of incomplete cross-tolerance and individual variability in opioid pharmacokinetics. 4) Use particular caution with methadone dose conversions because methadone has a long and variable half-life, and peak respiratory depressant effect occurs later and lasts longer than peak analgesic effect. 5) Use particular caution with transdermal fentanyl because it is dosed in mcg/hr instead of mg/day, and its absorption is affected by heat and other factors. 6) Buprenorphine products approved for the treatment of pain are not included in the table because of their partial µ-receptor agonist activity and resultant ceiling effects compared with full µ-receptor agonists. 7) These conversion factors should not be applied to dosage decisions related to the management of opioid use disorder.
^† Tapentadol is a µ-receptor agonist and norepinephrine reuptake inhibitor. MMEs are based on degree of µ-receptor agonist activity; however, it is unknown whether tapentadol is associated with overdose in the same dose-dependent manner as observed with medications that are solely µ-receptor agonists.
^§ Tramadol is a µ-receptor agonist and norepinephrine and serotonin reuptake inhibitor. MMEs are based on degree of µ-receptor agonist activity; however, it is unknown whether tramadol is associated with overdose in the same dose-dependent manner as observed with medications that are solely µ-receptor agonists.

Sources: Adapted from Von Korff M, Saunders K, Ray GT, et al. Clin J Pain 2008;24:521–7 and Nielsen S, Degenhardt L, Hoban B, Gisev N. Pharmacoepidemiol Drug Saf 2016;25:733–7.