Morphine Dosing & Tolerance

We’re are going to continue on the theme of opioids because this is Narcweek, it’s what we do. I do have more info/stories on Fentanyl, but I think they’re going to have to wait for another time…I wouldn’t want to wear you guys out on one drug when there are so many to cover. I want to continue on opioids, and what I want to demonstrate is that opioids really have no maximum as far as dosing goes. So what does this mean, and how is it relevant? Individuals can develop tolerance to opioids which means that over time, they may need increasing doses to receive the same effects. Because of this, you may see patients from time to time on extremely high doses that would certainly be lethal to opiate naïve individuals (i.e. those who aren’t on regular opioids). I had an example of this a while ago where a patient on hospice who was on 300mg of MS Contin three times per day, with a prn dose immediate release dose of 120 mg! That’s the highest dose of opioid I’d seen in quite some time. If you had to prescribe, administer, review or dispense this dose, it should scare the crap out of you. I have seen wrong patient med errors happen, and this is a case where it would likely have a chance to be fatal if given to the wrong individual. With usual starting doses in the ballpark of 5-15 mg orally, you can really see how this tolerance effect is demonstrated.


  1. Camea

    So tired but saw this post, worked hospice at length. All I have to say is True to above, no ceiling dose. Sad thing I’ve seen is people ignorant to this fact and never increase even when people have cancer and showing physical signs of pain. Worse yet then ignorance repeats itself and they label pt as drug seekers and more. Realistically dealing with pain in a safe, mature manner requires education, wisdom thought and best done IDT. Orders should be questioned and evaluated. Tt history and disease process must be factored in. Team Thx.

    • chri1599

      Great comment, thanks for sharing!

    • Heather

      My dad died a few days ago of Merkel cell cancer. Our doctors refused to increase his morphine after 3 months of 45mg twice daily MS Contin. As a caregiver I went ahead and increased to 60mg, and he became much more mobile shortly after that. His appetite also increased, I suspect from being in less pain.

      • chri1599

        I’m sorry to hear about your dad…


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Written By Eric Christianson

November 16, 2013

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