While both oxycodone and morphine trigger rapid increases in the brain\u2019s dopamine output, oxycodone\u2019s effects last much longer and lead to more extensive alteration of brain chemistry, a new study finds. All opioid-based drugs and medications have the ability to produce changes in human brain chemistry that result in physical dependence and addiction. However, not all opioids trigger the same level of dependence\/addiction risk in substance abusers. In a study published in October 2014 in the European Journal of Neuroscience, researchers from the University of Michigan compared the addictive potential of the opioid oxycodone (a pain medication widely distributed in the U.S. and other countries) to the addictive potential of morphine, another opioid medication widely used as a treatment for certain forms of pain. Opioid Addiction Opioids get their name because they come directly from mind-altering chemicals found naturally in the plant known as the opium poppy, but they can also be made from a laboratory-based rearrangement of the opium poppy\u2019s chemicals or come entirely from manmade chemicals designed to mimic natural opioids. Regardless of their origins, all opioids access the brain through nerve cell sites called opioid receptors and boost the brain\u2019s levels of a pleasure-producing chemical called dopamine. Many people who develop opioid dependence start out by abusing an opioid-based drug or medication in order to repeatedly experience this sharp uptick in pleasurable sensation (although some misuse opioid medications for their pain-relieving effect). Unlike some forms of substance dependence, opioid dependence is not synonymous with the highly dysfunctional, uncontrolled pattern of substance intake that characterizes addiction. However, the persistent brain changes triggered by opioid dependence can easily lead to addiction, especially in individuals who receive no medical oversight from a prescribing doctor. Along with diagnosable opioid abuse, opioid addiction forms part of a condition called opioid use disorder. Oxycodone Oxycodone is a prescription opioid painkiller derived from laboratory modification of one of the opium poppy\u2019s natural mind-altering chemicals. Doctors primarily prescribe this medication for people who have persistent moderate or severe pain. While most people receive oxycodone in tablet or pill form, the medication also comes in a liquid that can be injected into a vein or muscle, or under the skin. Widely distributed oxycodone-based medications available in the U.S. include OxyContin, Percodan and Percocet. The federal government tracks nationwide abuse of OxyContin, one of the most commonly misused mind-altering medications in America, through a yearly project called the National Survey on Drug Use and Health. The most recent figures from this project indicate that roughly 492,000 adults and teenagers misused this medication at least once in 2013. Is Oxycodone Unusually Addictive? In the study published in the European Journal of Neuroscience, the University of Michigan researchers used laboratory-based experiments on rats to compare the addiction-related brain changes produced by oxycodone to the addiction-related brain changes produced by morphine, a powerful opioid medication typically used to relieve severe pain in people who need surgery or are recovering from a surgical procedure. In addition to its role as a medication, morphine is the source for heroin, the well-known opioid street drug. The researchers gave oxycodone and morphine to groups of rats with no history of exposure to either substance. Next, they used a chemical analysis to see how each medication altered the brain\u2019s output of pleasure-producing dopamine. After completing their analysis, the researchers found that both oxycodone and morphine trigger rapid increases in the brain\u2019s dopamine output. In the case of morphine, this increase is short-lived and typically ends within roughly 60 seconds. However, the dopamine increase triggered by oxycodone continues for a much longer period of time and leads to much more extensive alteration of normal brain chemistry than the changes produced by morphine. The study\u2019s authors note that no other research teams have previously reported a significant difference in the brain chemistry effects associated with oxycodone use and the brain chemistry effects associated with morphine use. They believe that the rapid and relatively long-lasting changes produced by oxycodone may have a substantial impact on the medication\u2019s ability to initiate the brain and behavioral alterations that form the basis of an opioid addiction. In other words, oxycodone may have an unusual, previously unrecognized capacity to set the stage for opioid addiction. In practical terms, this means that oxycodone use\/abuse may pose a greater risk than the use\/abuse of other opioid pain medications. The authors note the need for further research in order to fully explore oxycodone\u2019s potentially unique addiction-related effects.