Morphine Equivalent Dose (MME) Calculator
Convert opioid doses to morphine milligram equivalents (MME/day) using the CDC 2022 prescribing guideline conversion factors. Risk thresholds, methadone tiers, and fentanyl patch math included.
CDC 2022 risk band · Caution
≥ 2× overdose risk vs < 20 MME — CDC 2022 caution (50 – 89 MME/day).
Show working
10 mg oxycodone × 4/day × 1.5 = 60 MME/day
Frequently asked questions
Per the CDC 2022 Clinical Practice Guideline (MMWR rr7103a1), a daily total of 50 MME/day or more is associated with at least double the overdose risk compared with under 20 MME/day, and 90 MME/day or more is the threshold at which the CDC advises clinicians to avoid or carefully justify the dose. These thresholds are guidance, not bright legal lines — context matters (cancer pain, palliative care, opioid-tolerant patients).
Per the CDC 2022 conversion table, transdermal fentanyl is converted as mcg/hr × 2.4 = MME/day. Example: a 25 mcg/hr patch delivers 25 × 2.4 = 60 MME/day. A 50 mcg/hr patch delivers 120 MME/day, already above the 90 MME high-risk threshold.
Tramadol is a weak μ-opioid receptor agonist with additional serotonin-norepinephrine reuptake inhibition (SNRI). The CDC 2022 conversion factor is 0.2 — so 50 mg tramadol equates to roughly 10 MME. Despite the low factor, tramadol carries seizure and serotonin-syndrome risks and is not a free pass relative to morphine.
Methadone has a long, variable elimination half-life (8–59 hours) and nonlinear potency that increases with dose. The CDC 2022 guideline uses tiered multipliers rather than a single fixed factor: 1–20 mg/day uses ×4, 21–40 mg/day uses ×8, 41–60 mg/day uses ×10, and ≥ 61 mg/day uses ×12. This calculator applies the tier matching the entered total daily dose.
No. This is an educational reference based on CDC 2022 population-level conversion factors. Real opioid rotation requires individual assessment by a pain specialist because cross-tolerance is incomplete, pharmacogenetics vary (CYP2D6 for codeine and tramadol; CYP3A4 for fentanyl and methadone), and renal or hepatic function changes the picture. The Switch mode applies standard 25–50% cross-tolerance discounts only for reference.
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