Study Could Pave the Way for Non-Addictive Painkillers
Opioids, Pain Relief and Addiction
All opioid substances, including prescription medications and illicit/illegal drugs, reach the brain by accessing chemical pathways called opioid receptors. There are different types of opioid receptors inside the brain. Some receptors give opioid substances the ability to block the brain’s capacity to receive or respond to pain signals generated elsewhere in the body. These same receptors help give opioid substances the ability to produce a powerful form of pleasure called euphoria. Unfortunately, this means that all opioid medications inevitably simultaneously trigger a reduced susceptibility to pain and significantly increased exposure to euphoric pleasure. This is critically important, because a repeated desire to feel euphoric pleasure is a common starting point for abusive patterns of substance intake that ultimately result in the onset of opioid addiction.
Opioid Abuse Statistics
Figures released by the federal Centers for Disease Control and Prevention (CDC) indicate that doctors in the U.S. provide prescription opioids to their patients hundreds of millions of times every year. Perhaps not coincidentally, opioid medications are America’s most common target for prescription drug abuse. Nationwide survey information from another federal agency called the Substance Abuse and Mental Health Services Administration indicates that about 1.7 percent of all U.S. adults, teenagers and preteens engage in opioid prescription misuse/abuse in the typical month. This is nearly three times the rate associated with the next most popular target of prescription drug misuse/abuse (sedative-hypnotic medications classified as tranquilizers). Specific opioid medications abused most often include OxyContin (based on an opioid called oxycodone) and Vicodin (based on another opioid called hydrocodone).
Opioid medications are common sources of opioid use disorder (diagnosable opioid abuse/addiction), although much of the public’s attention centers on the addictive potential of the street drug heroin. Opioid medications are also a more common source of opioid-related overdose than heroin. According to data released by the CDC in 2014, roughly 46 Americans died every day from a medication-based opioid overdose in the year 2012. In addition to their own links to addiction and overdose, prescription opioids frequently act as a gateway to heroin consumption, including involvement in the exceedingly dangerous practice of IV heroin injection. Cost and ease of access commonly drive the transition from prescription opioid misuse/abuse to heroin intake.
Pain Relief Without Opioids
In the study published in Nature Structural & Molecular Biology, researchers from institutions including the University of Southern California, Belgium’s Free University Brussels, Germany’s University of Hamburg and Canada’s Clinical Research Institute of Montreal used advanced X-ray technology to explore the possibility of using non-addictive substances to provide the level of pain relief normally associated with the use of addictive opioid medications. Specifically, the researchers wanted to know if it’s possible to access the opioid receptors used by opioid medications (thereby providing the desired pain relief) while simultaneously preventing any increase in addiction-promoting euphoria by blocking access to a second set of opioid receptors.
During the study, the researchers used a customized chemical compound specifically designed to produce pain relief while preventing euphoria. They used advanced X-ray procedures and other modern technologies to examine the ways in which this compound interacts with the brain’s opioid receptors. The researchers ultimately determined that the test compound triggered the desired effects and activated pain-relieving pathways inside the brain while simultaneously reducing euphoria production.
In order to determine the effectiveness of the test compound, the researchers had to examine the brain’s opioid receptors in great detail. They believe the knowledge gained from this close inspection contributes greatly to general understanding of opioids’ effects on the brain, as well as to the eventual production of a new class of non-addiction-promoting pain medications.