Converting Hydromorphone 4 mg to Oxycodone
When transitioning from hydromorphone 4 mg to oxycodone, the recommended dosage is 20 mg of oral oxycodone daily, which should be reduced by 25-50% to 10-15 mg daily to account for incomplete cross-tolerance. 1
Conversion Process
- Calculate the total daily hydromorphone dose (4 mg in this case) 2, 1
- Apply the conversion ratio: 4 mg oral hydromorphone is equivalent to 20 mg oral oxycodone 1, 3
- Reduce the calculated equianalgesic dose by 25-50% to account for incomplete cross-tolerance, resulting in 10-15 mg oxycodone daily 2, 1
- Divide the daily oxycodone dose by the number of doses per day (e.g., for 4 doses per day, 10-15 mg daily would equal 2.5-3.75 mg per dose) 1
Dosing Considerations
- If pain was effectively controlled with hydromorphone, use the reduced dose (10-15 mg daily) 2
- If pain was poorly controlled with hydromorphone, consider using 100% of the equianalgesic dose (20 mg daily) or even increasing by 25% (25 mg daily) 2, 1
- No washout period is needed when converting between these two pure opioid agonists 1
Breakthrough Pain Management
- Provide short-acting oxycodone rescue doses during the transition period 1
- Breakthrough doses typically should be 10-15% of the total daily dose 1
- Monitor the patient's response and adjust the dose accordingly 2
Important Clinical Considerations
- Patient variability means suggested doses are approximate and clinical judgment must be used to titrate to the desired response 2
- Consider patient-specific factors such as age, renal/hepatic function, and comorbidities when determining the final dose 1
- Research shows that hydromorphone and oxycodone have similar efficacy and safety profiles when appropriately dosed 4, 5
- For extended-release formulations, ensure the total daily dose is appropriately calculated before converting to the extended-release schedule 6
Potential Pitfalls
- Avoid using fixed conversion ratios without clinical judgment 1
- Be cautious of underdosing or overdosing during the transition period 1
- Monitor for adverse effects such as nausea, constipation, somnolence, and dizziness, which are common with both medications 4, 5
- Ensure the patient understands the dosing schedule and importance of taking medications as prescribed 2