Morphine Milligram Equivalent (MME)

What is it? Why is it important? And how do I easily incorporate it into my opioid prescribing?

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In all cases of managing dental pain, the evidence is clear that non-opioids are the best and safest choice.  

However, there are infrequent times when refractory pain or an intolerance to NSAIDs and Acetaminophen may require the use of opioid analgesics.

If you prescribe opioids, you should be certain that you are complying with CDC guidelines for responsible opioid prescribing and best practice.

These guidelines are based on the MME, the Morphine Milligram Equivalents. They allow a comparison between different opioids relative to strength and addiction potential. The chart below shows the comparison.

The relative pain control efficacy of opioids*

*Brand names are used only for historical identification. Hydrocodone and Oxycodone are primarily available only in generic formulations.

 

As per the chart, Morphine, which is rarely used in dentistry, is assigned a pain control effectiveness value of 1. The other opioids are compared to that value and assigned their relative morphine milligram equivalents (MME).

Morphine in the middle

The comparison documents that Tramadol and Codeine are much less effective than the other opioids. Still, like all pain control medications, they can have a placebo effect, which can be very effective for many people.

However, those drugs would not be a first choice for a patient in pain who cannot take Ibuprofen and/or Acetaminophen. Plus, Codeine is commonly associated with stomach upset, nausea, and vomiting, which is not what you (or they) want.

You can also note that the last three opioids in the table are much more powerful than is needed for almost all pain associated with dental procedures. Plus, they pose a very high risk of addiction and/or overdose.

If you have to use an opioid for dental pain, the most effective and reasonable ones are Hydrocodone and Oxycodone. They pose the least risk of untoward effects, but in most situations are less effective at controlling pain than the non-opioids. Regardless of the MME, ALL opioids have the potential for misuse and addiction and should be prescribed responsibly.

Here are the common dental use opioid prescriptions, based on MME calculated, CDC-compliant prescribing protocols.