This webinar will present the epidemiology of opioid overdose deaths. Background on the development of the International Classification of Diseases (ICD) System will be presented. The ICD-10 Codes T36 through T39 Poisoning by drugs and biological substances will be provided and an additional deeper dive into ICD-10 Code T40 Poisoning by Narcotics will be given. Participants will understand the pharmacological background of opioids and various types, including opium, heroin, and other natural and synthetic opioids, including fentanyl and carfentanil. Data from the CDCs WONDER database that was analyzed and mapped will be presented for regions across the nation illustrating where the fentanyl and other synthetic opioid overdose deaths occur.