What is the equivalent dose in Morphine Milligram Equivalents (MME) of 12 milligrams of intravenous (IV) hydromorphone?

MME Calculation for 12 mg IV Hydromorphone

12 mg of IV hydromorphone equals 48 MME (Morphine Milligram Equivalents). 1

Calculation Method

The CDC Guideline for Prescribing Opioids for Chronic Pain establishes that hydromorphone has a conversion factor of 4 when calculating morphine milligram equivalents, meaning 1 mg of hydromorphone equals 4 mg of morphine in MME terms. 1

Direct Calculation

• 12 mg hydromorphone × 4 = 48 MME 1

Important Context About This Conversion

This conversion factor applies regardless of route of administration (IV or oral) when calculating MME for comparison purposes. 1 The CDC conversion factors are standardized for MME calculations and do not differentiate between routes. 1

Critical Distinction: MME vs. Equianalgesic Dosing

• MME calculations are for comparison purposes only and should not be confused with equianalgesic dosing when switching patients between medications. 1
• When converting from IV morphine to IV hydromorphone for actual clinical dosing (not MME calculation), a ratio of approximately 5:1 is used (10 mg IV morphine = 2 mg IV hydromorphone). 2, 1
• The potency relationship shows hydromorphone is approximately 5-7 times more potent than morphine in clinical practice. 2, 1

Common Pitfall to Avoid

Do not confuse the MME conversion factor (1:4) with the clinical equianalgesic ratio (approximately 1:5-7). 1 The MME conversion factor of 4 is specifically designed for standardized comparison and monitoring purposes, while equianalgesic ratios guide actual dose conversions when switching medications. 1

Clinical Safety Considerations

• When converting between opioids in actual practice, incomplete cross-tolerance should be considered, requiring dose reduction of 25-50% when switching to a new opioid. 1, 3
• Patients should be monitored closely after any opioid conversion for both pain control and potential adverse effects. 1