Morphine milligram equivalent (MME) is used to describe which of the following?

• A. It remains fixed for days supply
• B. It is irrelevant to prescription
• C. It can change daily
• D. It only changes monthly

Answer: (C)

MME reflects the total potency of opioids a patient receives in a 24-hour period. Because that daily dose can be adjusted or swapped for a different opioid, the daily MME can change from day to day. It isn’t a fixed value for a whole days-supply, it isn’t irrelevant to prescribing, and it doesn’t only change on a monthly basis. For example, if today a patient is taking a certain amount that sums to 80 mg of MME in 24 hours, and tomorrow the dose is increased so the 24-hour total becomes 120 mg, the MME has risen accordingly. In practice, MME is a day-to-day measure used to compare opioid potencies and guide safe dosing, so it naturally varies with the actual daily dose.