Sink or Swim? Helping Patients and Practitioners to Understand Opioid Potencies and Overdose Risk
This bulletin shares a communication and risk assessment tool specific to opioids. The tool, which is designed in the form of an infographic, is directed specifically to patients and their healthcare practitioners.
INTRODUCTION
When prescribing opioids, practitioners are challenged with recognizing their patients’ exposure to risks and balancing these risks with improvements in pain control and functional ability. Although opioids are often classified as a single group, individual agents differ in relative analgesic potency, as well as the potential risk of harm to patients. Furthermore, the availability of numerous opioid formulations, each with distinct physical and pharmacological characteristics (e.g., immediaterelease oral dosage forms, long-acting oral dosage forms, topical patches, formulations for injection), adds to the difficulty of assessing potential harm.1
Even when the benefits and risks have been identified, practitioners may struggle with how to share this information in a meaningful manner with their patients. Few resources exist to engage and educate patients about the relative potency of their opioid therapy and the associated risks of harm. This identified gap led to the development of a communication and risk assessment tool specific to opioids. The tool, which is designed in the form of an infographic, is directed specifically to patients and their healthcare practitioners.
MORPHINE MILLIGRAM EQUIVALENTS
Morphine is used as the standard for comparing the analgesic potencies of different opioids. Healthcare practitioners can determine daily opioid consumption by first converting a patient’s opioid dose to morphine milligram equivalents (MME*) and then calculating the total daily intake, expressed as morphine milligram equivalents per day (MME/D†). A higher MME/D value is associated with a greater risk of overdose and increased complications from opioid therapy.
However, the calculation of MME is not always straightforward. Although there is general agreement among equianalgesic dosing tables, there are some conversion-factor differences between tables from different resources (e.g., the US Centers for Disease Control and Prevention guideline2 and the 2010 Canadian guideline1). The direction of conversion (e.g., morphine to oxycodone versus oxycodone to morphine) and the calculation of dose equivalency when changing the route of administration (e.g., oral to topical) can also be problematic. Discrepancies can lead to differences in the assessment of risk, possibly resulting in unsafe changes to pain management strategies.
The opioid infographic − Navigating Opioids for Chronic Pain (see page 3) is intended to help prescribers, pharmacists, patients, and their caregivers to understand the concept of morphine equivalence, the increased risk of harm at higher levels of morphine milligram equivalents per day (MME/D), and where in the risk profile a specific opioid regimen exists
USE OF THE OPIOID INFOGRAPHIC
The 2017 Canadian Guideline for Opioids for Chronic Non-Cancer Pain3 strongly recommends a prescribed dose less than 90 MME/D. For individuals already on a higher dose of opioid, the guideline recommends a taper to the lowest effective dose. The threshold dose of 90 MME/D is much lower than that published in the previous Canadian guideline, which recommended a “watchful dose” of 200 MME/D.1 This new daily dose limit also aligns with the recommendation in the 2016 guideline from the US Centers for Disease Control and Prevention.2
The 2017 Canadian Guideline for Opioids for Chronic Non-Cancer Pain strongly recommends limiting the prescribed opioid dose to less than 90 morphine milligram equivalents per day (MME/D).
Healthcare practitioners, patients, and caregivers can use the infographic to confirm and reinforce their own understanding of opioid morphine equivalencies, with respect to both analgesic potency and risk of harm. Together, they can use the infographic to determine where on the morphine equivalency scale an individual’s opioid regimen lies, to guide monitoring as well as therapy decisions.
The infographic can be used in the following situations:
Prescribers
- To support clinical decisions and discussions with patients about opioids
- To address a patient’s request for a dose increase, extra refill, or early part-fill (i.e., refill requested before the specified refill interval has been reached) by showing where on the scale a patient’s usage pattern lies
- To help patients understand how tapering opioids can reduce the risk of harm if the current dose causes complications or does not significantly improve function and pain control
- To heighten prescribers’ awareness of their patients’ risk of harm from opioids when receiving feedback from monitoring agencies.
Pharmacists
- To identify patients taking high MME/D who are at greater risk for complications, so they can be offered take-home naloxone kits
- To visually explain the risk of complications and overdose associated with opioids
- To provide the rationale for not dispensing an opioid medication (e.g., early part fill) by showing where on the scale a patient’s usage pattern lies
Patients and Caregivers
- To recognize their current risk of harm and complications
- To visualize how changes to their pain medication regimen can influence whether they “sink or swim”
- To recognize that taking more opioid medication than prescribed can increase the risk of harm
The opioid infographic resulted from collaboration between several organizations, including the University of Toronto Faculty of Medicine and Physicians for Responsible Opioid Prescribing. It aims to convey an individual’s risk for opioid-related harm in a visual and meaningful way. Practitioners caring for patients who are taking opioids can use the infographic to assess the risk associated with patients’ pain medication regimens and to more easily convey various safety concepts.
There is no safe dose [of opioid]. Harms and complications can happen at any dose, but are less likely at lower MME/D.
The Canadian Medication Incident Reporting and Prevention System (CMIRPS) is a collaborative pan-Canadian program of Health Canada, the Canadian Institute for Health Information (CIHI), the Institute for Safe Medication Practices Canada (ISMP Canada) and Healthcare Excellence Canada (HEC). The goal of CMIRPS is to reduce and prevent harmful medication incidents in Canada.
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