What dose of OxyContin (oxycodone) is equivalent to one Tylenol 3 (codeine and acetaminophen) tablet?

Oxycodone to Tylenol #3 Conversion: Dosage Equivalence

One 5mg oxycodone tablet (OxyContin) is approximately equivalent to two Tylenol #3 tablets (codeine 30mg/acetaminophen 325mg per tablet). This conversion is based on morphine milligram equivalent (MME) calculations from the CDC guidelines 1.

Understanding the Conversion

Morphine Milligram Equivalent (MME) Calculation:

1. Tylenol #3 (codeine 30mg/acetaminophen 325mg):

   • Codeine conversion factor: 0.15 1
   • MME per tablet: 30mg × 0.15 = 4.5 MME
   • Two tablets = 9 MME

2. OxyContin (oxycodone):

   • Oxycodone conversion factor: 1.5 1
   • 5mg oxycodone = 7.5 MME

Practical Application:

• One 5mg oxycodone tablet provides slightly less analgesia than two Tylenol #3 tablets
• For exact equivalence, 6mg of oxycodone would equal two Tylenol #3 tablets

Clinical Considerations

Efficacy Differences:

• Oxycodone has more predictable metabolism and efficacy compared to codeine 2
• Codeine is a prodrug requiring conversion to morphine by CYP2D6 enzyme
• 7-10% of Caucasians and up to 30% of Asians are poor metabolizers of codeine, resulting in reduced efficacy 2

Side Effect Profiles:

• Both medications can cause:
  • Constipation
  • Nausea/vomiting
  • Respiratory depression
  • Sedation

Important Warnings:

• OxyContin (extended-release oxycodone) should NOT be used for acute pain management 1
• Only immediate-release oxycodone should be considered when converting from Tylenol #3
• Long-acting opioids are for opioid-tolerant patients only 1

Dosing Recommendations

For Converting from Tylenol #3:

• Start with immediate-release oxycodone 5mg every 4-6 hours PRN 1
• Monitor for side effects including respiratory depression
• Use the lowest effective dose for the shortest duration possible 1

Risk Mitigation:

• Doses ≥50 MME/day significantly increase risk of adverse outcomes 1
• Carefully reassess benefits and risks before increasing total opioid dosage to ≥50 MME/day
• Consider non-opioid alternatives when possible 1

Cautions and Contraindications

• Avoid initiating OxyContin in opioid-naïve patients 1
• Exercise caution when converting between opioids due to incomplete cross-tolerance 1
• The calculated MME dose should not be used directly when converting between opioids; typically start with a lower dose than calculated 1
• Monitor patients closely during conversion periods for efficacy and side effects

Remember that opioid conversion is not an exact science and requires careful clinical judgment and monitoring. The goal should always be to use the lowest effective dose for the shortest necessary duration.