Fentanyl is a powerful opioid used used for pain relief and, sometimes as a recreational drug. In the last few years, counterfeit fentanyl coming into the United States from China and Mexico is being mixed with heroin, cocaine, or methamphetamine, and its potentially deadly overdose effects can be neutralized by naloxone. Fentanyl is also commonly used to create counterfeit drugs sold on the street as OxyContin, Xanax, Adderall, and other pills. In medical settings, Fentanyl is administered via injection, nasal spray, or skin patch, or absorbed through the cheek as a lozenge or tablet. Fentanyl now causes more fatal overdoses in the US than any other drug.