Synthetic Opioids and the Ongoing Epidemic

Michael Prucha, MD, MPH
Emergency Medicine Resident
Brown University, Department of Emergency Medicine

As the opioid use epidemic continues to rage and the associated death toll continues to rise, Emergency Medicine providers remain at the front lines of the crisis. This article will touch upon the drugs and analogues currently believed to be the causes of this up-spike in opioid deaths.

The current opioid The Centers for Disease Control and Prevention (CDC) reports that greater than 28,000 deaths were related to the use of opioids in 20141 with 8200 deaths being directly related to heroin, both numbers larger than any other year on record2.

While many are aware of the common prescription pills such as oxycodone, oxycontin and hydrocodone, as well as heroin, other synthetic opioids have been making their way into the mix, increasing the danger of the epidemic, as many of these drugs have a much greater potency than the most commonly abused opioids. Keeping abreast of the reported and likely contributors to the morbidity and mortality of the current crisis is essential. Much of the data are still emerging, and it may not be the routine practice of your local medical examiner to test for these sometimes old, but newly emerging killers.  The information below is still forthcoming and is presented as we understand it currently; the data will be subject to change as new facts are available about these substances. The National Drug Early Warning System at the Center for Substance Abuse Research of the National Institute on Drug Abuse provides a centralized resource for what is new and upcoming among recreational drug abusers, including details about the current opioid epidemic. 

Fentanyl, initially developed as a pain control agent, has now been increasingly found among those using illicit drugs, leading to overdose and death due to a more potent opioid effect3,4,5. In fact, 2014 brought nearly a 500% increase in fentanyl-use associated deaths6. Fentanyl analogues like remifentanil and sufentanil also have a more potent opioid effect, and have the potential for abuse like all other opioids when in the wrong hands.

U-47700, developed in the 1970s as a derivative of the less potent AH-7921, is a synthetic opioid which is reportedly 7-8x stronger than morphine7.  This drug has been linked to recent ICU admissions in Dallas, Texas for respiratory depression, and internationally has been linked to several deaths in combination with fentanyl8. If this substance continues to be available at relatively low cost, emergency providers are more than likely to come across patients in need of their assistance due to its effects.

Finally, recent reports have suggested that another substance, known as W-18, has recently been contributing to drug poisoning deaths.  The data about this drug are still unclear, including whether or not this substance is actually an opioid, though several reports seem to suggest the potency is up to 10,000 times that of morphine. There have been several recent case reports of this drug being found among suspected opioid overdose deaths. Unfortunately however, the medical community is still trying to understand this substance, and as such, the role and efficacy of naloxone in the reversal of this drug has not been proven7,9,10.

Keeping abreast of the newest developments in the opioid abuse epidemic including those drugs shown to have been involved in causing significant morbidity or mortality, as well as doing our part as prescribers of opioids to limit our role in overprescribing/misprescribing for conditions in which narcotic medications are unwarranted are both critical steps in combating this affliction.  We have the power to recognize, report and prevent unnecessary and untimely deaths, and the capacity, education and knowledge to begin to change the course of this epidemic.


Potency (relative to morphine)

















Table 1: Synthetic opioids and their commonly reported potencies

(*Unknown whether classified as opioid)

References upon request



Return to Newsletter

[ Feedback → ]