Dosing Tables for Painkillers 'Fraught with Danger'

By Pat Anson, Editor

Opioid dosing tables that are widely used by doctors, insurers and regulators to determine what constitutes a safe level of opioid medication are "fraught with danger" and could result in patients being under-dosed or overdosed, according to a leading physician's group.

Equianalgesic dosing tables are used to calculate and convert opioid pain medication into milligrams of morphine equivalent daily doses -- often abbreviated as MEDD or MME. The Centers for Disease Control and Prevention, for example, has set 90mg MME as the highest recommended daily dose for most chronic pain patients in its opioid prescribing guideline.

But a new white paper by the Academy of Integrative Pain Management (AIPM) questions the science behind MME conversion tables and whether they are appropriate to use in a one-size-fits-all approach to pain care.

“We felt it was necessary to outline our concerns about the key concept of equianalgesic dosing,” said Bob Twillman, PhD, Executive Director of AIPM. “We have seen policymakers and payers both relying on this concept as if it was based on solid science, and as if individual differences in a number of factors wasn’t important in clinical practice. Doing so can expose patients to significant risks."

Some opioids have different mechanisms of action on opioid receptors in the brain. Patients could also have genetic or biological differences that slow or speed-up the absorption of opioids into the body -- making them either more potent or less effective. As a result, two patients taking identical doses of the same opioid could have different levels of it in their bloodstream an hour later.

None of these differences were recognized by the CDC, Centers for Medicare and Medicaid Services or the Department of Veterans Affairs when they set limits in their opioid guidelines on what constitutes a recommended "safe" dose of pain medication.   

"The practice of setting arbitrary milligram dosing cut-offs as suggested by various regulatory agencies and legally allowed by some states is an attempt to pigeon hole providers into ignoring the approach to medicine," the white paper states. "Rather than assigning irrational rules based on pseudoscience, the regulatory agencies including the CDC and state governments should be targeting ways to increase knowledge and education with regard to opioids to foster safe and efficacious prescribing practices."

Many different opioid calculators and apps are available to help doctors convert oxycodone, hydrocodone, tramadol and other opioid medications into MEDDs or MMEs. It's a common practice that may give physicians peace of mind in complying with government guidelines and insurance company policies. But for patients the benefits are less clear -- and so is the science.

“I’ve been researching and writing about the problems with equianalgesic dosing for the past several years," said Jeffrey Fudin, PharmD, lead author of the white paper. “As I studied this concept, I was shocked by the poor quality of the studies underlying it and by the dramatic clinical effects that could result from an uncritical use of published conversion tables.

"Add to that the fact that some opioid pain medications just don’t fit the concept because of their mechanisms of action, and you have the potential for some serious negative consequences if policies improperly use this information.”