Opioid Conversion Calculator

Select specific drugs and routes.
Use the mouse wheel, click and drag, or type a letter to cycle.

mg
%
From
To
Conversion Logic
Calculation based on standard equivalence tables.

Calculated Target Dose

-- mg
25% Reduction Applied

Clinical Pearls

  • Opioid Dose Conversion: When converting between different narcotics, always calculate the Morphine Milligram Equivalent (MME) baseline before selecting the target agent.
  • Cross-Tolerance Reduction: Incomplete cross-tolerance is common when switching opioids. A reduction of 25–50% is standard unless converting due to uncontrolled acute pain.
  • Methadone Conversions: Methadone kinetics are non-linear; higher baseline MME levels require significantly higher conversion ratios.
  • Fentanyl Unit Adjustment: Parenteral fentanyl is dosed in micrograms (mcg). This opioid converter automatically converts units between mg and mcg to prevent calculation errors.

References

  1. CDC Clinical Practice Guideline for Prescribing Opioids for Pain. MMWR Recomm Rep 2022;71(No. RR-3):1–95.
  2. McPherson ML. Demystifying Opioid Conversion Calculations: A Guide for Effective Dosing. 2nd ed. Bethesda, MD: ASHP; 2018.
  3. CMS. Opioid Oral Morphine Milligram Equivalent (MME) Conversion Factors. 2023.
  4. Treisman GJ, Clark MR. A Guide to Chronic Pain Assessment and Management. Johns Hopkins University Press; 2011.