What oral hydromorphone dose is equivalent to 20 mg of oxycodone immediate‑release in an adult patient?

Oral Hydromorphone Equivalent to Oxycodone IR 20mg

Based on the most recent NCCN 2025 guidelines, 20 mg of oral oxycodone immediate-release is equivalent to approximately 5-6 mg of oral hydromorphone.

Conversion Calculation

Using the NCCN 2025 equianalgesic table 1:

• Oral morphine 30 mg = Oral oxycodone 15-20 mg = Oral hydromorphone 7.5 mg

For 20 mg oxycodone IR:

• 20 mg oxycodone ≈ 30 mg oral morphine (using the 1:1.5 ratio)
• 30 mg oral morphine = 7.5 mg oral hydromorphone
• Therefore: 20 mg oxycodone ≈ 7.5 mg hydromorphone

However, the NCCN table shows a range for oxycodone (15-20 mg), and using the midpoint calculation:

• If 15 mg oxycodone = 7.5 mg hydromorphone
• Then 20 mg oxycodone = approximately 10 mg hydromorphone (direct proportion)

The ESMO 2018 guidelines provide a more conservative ratio of oral oxycodone to oral hydromorphone of 1:4 2, which would suggest:

• 20 mg oxycodone ÷ 4 = 5 mg hydromorphone

Critical Safety Recommendation

When converting between opioids, reduce the calculated equianalgesic dose by 25-50% to account for incomplete cross-tolerance 3. This is essential to prevent overdosing.

Practical Application:

1. Calculate equianalgesic dose: 20 mg oxycodone = 7.5-10 mg hydromorphone
2. Reduce by 25-50%: Start with 4-6 mg oral hydromorphone
3. Provide immediate-release hydromorphone for breakthrough pain (10-15% of total daily dose)
4. Titrate upward based on pain control and adverse effects

Important Caveats

• Renal impairment: Hydromorphone metabolites accumulate in renal dysfunction. Use with extreme caution and start at lower doses 1. Consider fentanyl or methadone as safer alternatives in severe renal impairment (CrCl <30 mL/min) 2, 4.

• Individual variability: The conversion factor between IV and oral hydromorphone ranges from 2.5-5 1, reflecting significant pharmacokinetic variability between patients.

• Pain control status: If the patient's pain was poorly controlled on oxycodone 20 mg, you may use 100% of the equianalgesic dose (7.5-10 mg) or even increase by 25% 3. If pain was well-controlled, the 25-50% reduction is mandatory.

• Dose frequency: Hydromorphone IR has a shorter duration of action (2-3 hours) compared to oxycodone IR (3-5 hours) 1, so dosing every 3-4 hours may be needed versus every 4-6 hours for oxycodone.