What is the equivalent dose of morphine (intravenous) for 0.5mg of hydromorphone (Dilaudid) (intravenous)?

Hydromorphone to Morphine IV Conversion

0.5 mg IV hydromorphone (Dilaudid) is equivalent to approximately 2 mg IV morphine.

Conversion Factor

• The CDC establishes a conversion factor of 4 for hydromorphone, meaning hydromorphone is 4 times more potent than morphine 1
• Using this conversion factor: 0.5 mg hydromorphone × 4 = 2 mg morphine equivalents 1

Supporting Evidence from Clinical Studies

• A 2017 study examining IV to oral conversions found that the relative potency relationships support the 1:4 ratio for hydromorphone to morphine equivalents 2
• The conversion table from CDC guidelines confirms this 4:1 potency ratio is the standard for calculating morphine milligram equivalents (MME) 1

Clinical Application

• For direct IV conversion: 0.5 mg IV hydromorphone = 2 mg IV morphine 1
• This conversion applies when switching between these medications for equivalent analgesic effect 1

Important Caveats

• When rotating between opioids in practice, reduce the calculated equianalgesic dose by 25-50% to account for incomplete cross-tolerance 3
• If converting this patient from hydromorphone to morphine, start with 1-1.5 mg IV morphine (50-75% of the calculated 2 mg dose) rather than the full 2 mg 3
• Conversion factors are estimates and cannot account for individual variability in genetics and pharmacokinetics 1
• Monitor closely for oversedation or inadequate analgesia during the first 24-72 hours after conversion 3