Opioid Conversion Guidelines for Hydromorphone

Introduction to Opioid Conversion

For a patient taking 40mg of oral oxycodone daily, the equivalent dose of oral hydromorphone is approximately 7.5 mg daily, which should be reduced by 25-50% to 3.75-5.6 mg daily when converting between opioids to account for incomplete cross-tolerance, as recommended by the National Comprehensive Cancer Network 1, 2

The Centers for Disease Control and Prevention (CDC) establishes a conversion factor of 1.5 for oxycodone to morphine equivalents, which can be used to calculate the morphine milligram equivalents (MME) per day 3
Using the conversion table, 60 mg oral morphine is equivalent to 7.5 mg oral hydromorphone, according to the National Comprehensive Cancer Network 1
The CDC conversion factor for hydromorphone is 5.0, meaning hydromorphone is 5 times more potent than morphine 3

The National Comprehensive Cancer Network recommends starting with 5-7.5 mg oral hydromorphone daily, divided into doses every 4-6 hours, which is a 50-75% dose reduction from the calculated equianalgesic dose 1, 2
A conservative approach is to start with 1 mg every 4 hours (6 mg/day total), while a moderate approach is to start with 1.5 mg every 4 hours (9 mg/day total) only if pain was poorly controlled on oxycodone 1, 2

The National Comprehensive Cancer Network and the CDC recommend always reducing the calculated equianalgesic dose by 25-50% when rotating between opioids to account for incomplete cross-tolerance and individual pharmacokinetic variability 1, 2, 3
If the patient's pain was well-controlled on oxycodone 40 mg/day, use a 50% reduction (start with 5 mg hydromorphone/day), while if pain was poorly controlled, may use only a 25% reduction or start at full equianalgesic dose, but monitor closely 1, 2

The National Comprehensive Cancer Network warns to avoid hydromorphone (and morphine) in patients with renal failure due to accumulation of renally cleared metabolites that can cause neurotoxicity 2

The National Comprehensive Cancer Network recommends reassessing pain control and side effects within 24-48 hours of conversion, and titrating upward based on breakthrough medication requirements 1, 2
Monitor closely for signs of oversedation or respiratory depression, especially in the first 24-72 hours, as the peak respiratory depressant effect may occur at different times than peak analgesic effect 1, 2, 3