From the Guidelines
The total Morphine Milligram Equivalent (MME) for this regimen is 90 MME per day. This calculation includes 20 mg OxyContin (oxycodone extended-release) taken twice daily, which equals 40 mg of oxycodone per day, plus 10 mg immediate-release oxycodone taken twice daily, which equals an additional 20 mg of oxycodone per day. The total daily oxycodone dose is therefore 60 mg. Since oxycodone has a conversion factor of 1.5 when calculating MME (meaning oxycodone is 1.5 times more potent than morphine), we multiply the total daily oxycodone dose of 60 mg by 1.5 to get 90 MME per day, as indicated in the CDC clinical practice guideline for prescribing opioids for pain - United States, 2022 1.
This MME calculation is important for assessing the relative potency of opioid medications and evaluating the overall opioid burden, which helps healthcare providers monitor risk for adverse effects such as respiratory depression and assess the potential for opioid dependence. The CDC considers doses above 90 MME per day to be associated with higher risk for overdose, so this regimen is at the threshold where increased monitoring and consideration of risk mitigation strategies may be appropriate, as noted in the guideline 1.
Key considerations for managing patients on high-dose opioids include:
- Starting opioids at the lowest possible effective dosage
- Using caution when increasing opioid dosages and increasing dosage by the smallest practical amount
- Implementing additional precautions, including increased frequency of follow-up and considering offering naloxone and overdose prevention education, when the total opioid dosage reaches or exceeds 50 MME/day
- Carefully evaluating the decision to increase dosage beyond 50 MME/day based on individualized assessment of benefits and risks, as recommended in the CDC guideline 1.
By following these guidelines and carefully monitoring patients on high-dose opioids, healthcare providers can help minimize the risks associated with opioid therapy and optimize patient outcomes.
From the Research
Calculating Morphine Milligram Equivalent (MME)
To calculate the MME for 20 mg OxyContin (oxycodone) twice a day (BID) plus 10 mg Immediate Release (IR) oxycodone BID, we need to understand the conversion factors between oxycodone and morphine.
- The equivalence between oxycodone and morphine is reported as 1:2 in some studies 2, but for calculating MME, a more specific conversion factor is needed.
- According to general clinical guidelines, the conversion factor for oxycodone to morphine is approximately 1:1.5 to 1:2 for chronic pain management. However, for MME calculations, a specific factor is often used: 1 mg of oxycodone is equivalent to about 1.5 mg of morphine in terms of MME.
MME Calculation
Given:
- 20 mg OxyContin (controlled release) BID = 40 mg/day
- 10 mg IR oxycodone BID = 20 mg/day Total daily oxycodone dose = 40 mg + 20 mg = 60 mg
Using the conversion factor of 1 mg oxycodone = 1.5 mg morphine for MME: MME = 60 mg oxycodone * 1.5 = 90 mg
Summary of Findings
- The MME for the given regimen is calculated based on the total daily dose of oxycodone and the conversion factor to morphine.
- Studies provided do not directly address the calculation of MME but offer insights into oxycodone's pharmacology and clinical use 3, 4, 5, 2, 6.
- The calculation is based on general principles of opioid conversion and may vary depending on individual patient factors and clinical guidelines.