Question

NT is taking two PERCOCET tablets each containing 7.5 mg of oxycodone and 325 mg of acetaminophen every 4 hours to manage his pain. His physician wants to switch him to oxymorphone extended-release tablets (OPANA ER) for improved pain control. Oxymorphone extended-release tablets are available in strengths of 5, 7.5, 10, 15, 20, 30, and 40 mg to be given every 12 hours. What should be the dose and dosage regimen for this patient?

Answer 1

Conversion from oxycodone to OPANA ER

Step 1: Add the total daily dose of oxycodone

2 tablets each having 7.5 mg oxycodone q4 hr = 15 mg 4 times daily(QID)

=60 mg

Step 2: Compute the rough dose of oral oxymorphone according to the total daily dose of oxycodone.

60 mg * 0.5 mg conversion factor = 30 mg of oral oxymorphone daily.

(conversion factor table readily available)

Step 3: Compute the first dose of OPANA ER to be given every 12 hrs.

15 mg OPANA ER every 12 hours.

DOSE AND DOSAGE REGIMEN FOR THE PATIENT

• 15 mg OPANA ER orally every 12 hours as a starting dose for 3-7 days(as  steady-state plasma concentration are calculated as 3 days).
• Then 30 mg of oral oxymorphone daily.
• Oxymorphone should be administered 1 hour prior or 2 hours after eating.