Opioid Dosing and Safety Guidelines

Calculation and Conversion Factors

The Centers for Disease Control and Prevention (CDC) recommends using a conversion factor of 5.0 for hydromorphone when calculating the total daily morphine equivalent dose (MME) 1, 2
The CDC also recommends using a conversion factor of 0.15 for codeine when calculating the total daily MME 1, 2
The total daily MME can be calculated by multiplying the daily dose of each opioid by its respective conversion factor and summing the results, for example, 6 mg of hydromorphone per day equals 30 MME/day and 120 mg of codeine per day equals 18 MME/day, for a combined total of 48 MME/day 1

The CDC recommends pausing and carefully reassessing benefits versus risks before any further dose escalation when the total opioid burden approaches 50 MME/day 1, 2
Patients experiencing progressive increases in overdose risk without necessarily experiencing proportional improvements in pain control or function may be at a higher risk at dosages approaching 50 MME/day 1, 2
Before increasing beyond 50 MME/day, clinicians should pause and carefully reassess individual benefits and risks, as many patients do not experience benefit from higher doses 1, 2

The CDC updated the hydromorphone conversion factor from 4.0 to 5.0 in 2022, reflecting more recent evidence about hydromorphone's relative potency 1, 3
These conversion factors are specifically for calculating MME for comparison purposes only and should never be used directly when switching patients between opioids 1, 2
When actually converting between opioids, the new opioid should be dosed substantially lower (typically 25-50% reduction) than the calculated MME to avoid overdose due to incomplete cross-tolerance 1, 2, 4