What is the oral hydromorphone (Dilaudid) equivalent of 10mg of morphine?

Oral Hydromorphone Equivalent of 10 mg Morphine

The oral hydromorphone (Dilaudid) equivalent of 10 mg oral morphine is 2.5 mg. 1

Conversion Ratios

• The FDA-approved drug label for hydromorphone states that 5 mg of oral hydromorphone provides comparable analgesia to 30 mg of oral morphine, establishing a 1:6 ratio 1
• This means that 1 mg of oral hydromorphone is equivalent to 6 mg of oral morphine 1
• Therefore, 10 mg of oral morphine would be equivalent to approximately 1.67 mg of oral hydromorphone (10 ÷ 6 = 1.67) 1
• However, clinical studies have demonstrated that the actual equivalence ratio is closer to 1:4, meaning 1 mg of oral hydromorphone is equivalent to 4 mg of oral morphine 2
• Using this more clinically established ratio, 10 mg of oral morphine would be equivalent to 2.5 mg of oral hydromorphone (10 ÷ 4 = 2.5) 2

Clinical Considerations

• Hydromorphone is more potent than morphine on a milligram basis, with studies showing it is approximately 4-5 times more potent when given orally 2
• The bioavailability of oral hydromorphone is lower than that of parenteral hydromorphone, which must be considered when converting between routes 3
• When converting from IV to oral hydromorphone, a ratio of 1:2.5 is recommended (1 mg IV hydromorphone = 2.5 mg oral hydromorphone) 3

Potential Pitfalls in Opioid Conversion

• Different sources may cite slightly different conversion ratios, which can lead to dosing errors 4
• Older literature suggested a morphine to hydromorphone ratio of 7:1, but more recent clinical evidence with patient-controlled analgesia supports a ratio closer to 3:1 or 4:1 5
• Individual patient factors such as prior opioid exposure, renal function, and concomitant medications can affect the appropriate conversion ratio 6
• Hydromorphone metabolites may accumulate in patients with renal insufficiency, potentially leading to increased adverse effects 6

Practical Application

• When converting from morphine to hydromorphone, start with the calculated equivalent dose and consider reducing by 25-30% to account for incomplete cross-tolerance 6
• Monitor the patient closely after conversion for both efficacy and side effects 6
• Hydromorphone may be preferred in patients with morphine intolerance or those with renal insufficiency requiring lower doses of opioids 6