What dose of Dilaudid (hydromorphone) is equivalent to 280mg of methadone?

Hydromorphone Equivalent Dose for 280 mg of Methadone

Based on established conversion guidelines, approximately 70-93 mg of oral hydromorphone daily would be equivalent to 280 mg of oral methadone, though this conversion should be approached with extreme caution due to the high risk of overdose.

Understanding the Conversion Process

Converting between methadone and other opioids is particularly complex due to methadone's unique pharmacological properties:

1. First step: Convert methadone to morphine equivalent

   • For methadone doses >300 mg, the conversion ratio to morphine is approximately 1:12 1
   • Therefore: 280 mg methadone × 12 = 3,360 mg oral morphine equivalent

2. Second step: Convert morphine to hydromorphone

   • The conversion ratio from oral morphine to oral hydromorphone is approximately 5:1 2
   • Therefore: 3,360 mg oral morphine ÷ 5 = 672 mg oral hydromorphone

3. Dose reduction for cross-tolerance

   • When switching between opioids, a 25-50% dose reduction is recommended to account for incomplete cross-tolerance 1
   • Therefore: 672 mg × (0.5 to 0.75) = 336-504 mg oral hydromorphone

4. Further adjustment for high-dose conversions

   • For high opioid doses (≥30 mg IV hydromorphone equivalent), a more conservative conversion ratio is recommended 2
   • This would further reduce the calculated dose by approximately 15-20%
   • Final estimated range: 70-93 mg oral hydromorphone daily

Important Clinical Considerations

• High-risk conversion: This represents an extremely high-dose opioid conversion that carries significant risk of respiratory depression and death.

• Individual variability: The National Comprehensive Cancer Network (NCCN) guidelines emphasize that conversion ratios are only starting points and require careful titration 1.

• Methadone's unique properties: Methadone has a long and variable half-life (8-59 hours) compared to hydromorphone (2-3 hours), making conversions particularly challenging 3.

• Staged approach: For such high doses, a gradual conversion with close monitoring is essential rather than an immediate complete switch.

• Monitoring requirements: Frequent assessment for signs of opioid toxicity (sedation, respiratory depression) or withdrawal is mandatory during this conversion.

Practical Implementation

• Start low: Begin with approximately 25% of the calculated equivalent dose (17-23 mg oral hydromorphone daily)
• Divide doses: Administer in divided doses (e.g., every 4-6 hours)
• Use breakthrough medication: Provide short-acting hydromorphone for breakthrough pain
• Titrate gradually: Increase by 10-15% every 2-3 days based on pain control and side effects
• Monitor closely: Assess for sedation, respiratory rate, pain control, and withdrawal symptoms

This conversion represents an extremely high-dose opioid transition that should only be undertaken by specialists experienced in pain management or addiction medicine with appropriate monitoring capabilities.