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BackgroundThe US mainland is experiencing an epidemic of opioid overdoses. Unfortunately, the US Territories (Guam, Puerto Rico, and the Virgin Islands) have often been overlooked in opioid pharmacoepidemiology research. This study examined common prescription opioids over the last decade.MethodsThe United States Drug Enforcement Administration’s Automation of Reports and Consolidated Orders System (ARCOS) was used to report on ten medical opioids: buprenorphine, codeine, fentanyl, hydrocodone, hydromorphone, meperidine, methadone, morphine, oxycodone, and oxymorphone, by weight from 2006 to 2017. Florida and Hawaii were selected as comparison areas.ResultsPuerto Rico had the greatest Territorial oral morphine mg equivalent (MME) per capita (421.5) which was significantly higher (p < .005) than the Virgin Islands (139.2) and Guam (118.9) but significantly lower than that of Hawaii (794.6) or Florida (1,509.8). Methadone was the largest opioid by MMEs in 2017 in most municipalities, accounting for 41.1% of the total in the Virgin Islands, 37.9% in Florida, 36.6% in Hawaii but 80.8% in Puerto Rico. Puerto Rico and Florida showed pronounced differences in the distribution patterns by pharmacies, hospitals, and narcotic treatment programs for opioids.ConclusionsContinued monitoring of the US Territories is needed to provide a balance between appropriate access to these important agents for cancer related and acute pain while also minimizing diversion and avoiding the opioid epidemic which has adversely impacted the US mainland.

Buprenorphine, an analogue of thebaine, is a Schedule III opioid in the United States used for opioid-use disorder and as an analgesic. Research has shown drugs like buprenorphine have a complicated pharmacology with characteristics that challenge traditional definitions of terms like agonist, antagonist, and efficacy. Buprenorphine has a high affinity for the mu (MOR), delta (DOR), kappa (KOR), and intermediate for the nociceptin opioid receptors (NOR). Buprenorphine is generally described as a partial MOR agonist with limited activity and decreased response at the mu-receptor relative to full agonists. In opioid na&iuml;ve patients, the drug&rsquo;s analgesic efficacy is equivalent to a full MOR agonist, despite decreased receptor occupancy and the &ldquo;ceiling effect&rdquo; produced from larger doses. Some argue buprenorphine&rsquo;s effects depend on the endpoint measured, as it functions as a partial agonist for respiratory depression, but a full-agonist for pain. Buprenorphine&rsquo;s active metabolite, norbuprenorphine, attenuates buprenorphine's analgesic effects due to NOR binding and respiratory depressant effects. The method of administration impacts efficacy and tolerance when administered for analgesia. There have been eleven-thousand reports involving buprenorphine and minors (age &lt; 19) to US poison control centers, the preponderance (89.2%) with children. The consequences of prenatal buprenorphine exposure in experimental animals and humans should continue to be carefully evaluated. In conclusion, buprenorphine&rsquo;s characterization as only a partial mu-agonist is an oversimplification. Contemporary research shows the traditional explanation of the pharmacology of buprenorphine does not take into account changes to receptor theory, pharmacological terminology, route of administration, and biologically active major metabolites.