The effectiveness and ease of use of the newer intranasal formulation of Narcan (naloxone) is shown well here. Naloxone is a medication used to treat opioid overdose, it is a mu-opioid full antagonist meaning it blocks the opioid receptors in the brain and central nervous system. When a person overdoses on an opioid the function of the central nervous system is suppressed, this manifests in the form of the CNS being unable to cause the diaphragm to expand and contract making it impossible to breathe. Naloxone works by deactivating the opioid receptors and quickly restores breathing to normal. Naloxone was first discovered in 1961 and for many years was only available in intravenous and subcutaneous injectable formulations, by prescription only. As a response to the United States growing epidemic of opioid addiction and overdose an easy to use, intranasal formulation of naloxone was developed and FDA approved in 2015. This formulation works almost as quickly and effectively as the intravenous formulation and has the benefit of being extremely easy to use; instead of having to fill a syringe from a vial, all one needs to do is open the package, insert the nozzle into the overdosing person's nostril and squeeze the plunger. The medication is then absorbed through the skin in the upper part of the nasal cavity directly into the bloodstream and takes effect in less than a minute. For the most part naloxone has been a prescription only medication, but as the opioid epidemic has gotten worse many states have started programs to provide first responders will Narcan Nasal Spray kits, which has helped to save a lot of lives, especially with the recent epidemic of fentanyl laced heroin and counterfeit fentanyl tablets entering the US from Mexican drug cartels. Since 2020 a number of states have seen a sharp increase in fatal opioid overdoses, especially in young adults and teens, due to fentanyl laced products. As an effort to combat the fentanyl flooding the streets as of 2022, 29 US states have made naloxone available as a behind the counter medication, meaning it does not require a prescription from a physician but instead can be directly dispensed by a licensed pharmacist. Some states have also implemented requirements for patients being prescribed long acting opioids for chronic pain to be provided with a Narcan kit in case of accidental overdose.