<unk> , also spelled<unk> , is a powerful opioid used as a pain medication and, together with other medications, for anesthesia. It is also used as a recreational drug, sometimes mixed with heroin, cocaine, or methamphetamine. Its potentially deadly overdose effects can be neutralized by naloxone.<unk>  is commonly used to create counterfeit drugs marketed as OxyContin, Xanax, Adderall, and other pills. It has a rapid onset and its effects generally last under two hours. Medically, it is used by injection, nasal spray, or skin patch, or absorbed through the cheek as a lozenge or tablet. Common side effects of<unk>  include nausea, vomiting, constipation, itching, sedation, confusion, and injuries related to poor coordination. Serious side effects may include respiratory depression, hallucinations, serotonin syndrome, low blood pressure, or development of an opioid use disorder.<unk>  works primarily by activating μ-opioid receptors. It is around 100 times stronger than morphine and about 50 times stronger than heroin. Some<unk>  analogues such as carfentanil are up to 10,000 times stronger than morphine.<unk>  was first made by Paul Janssen in 1960 and approved for medical use in the United States in 1968. In 2015, were used in healthcare globally. ,<unk>  was the most widely used synthetic opioid in medicine; in 2019, it was the 278th most commonly prescribed medication in the United States, with more than 1million prescriptions. It is on the World Health Organization's List of Essential Medicines. Starting around 2013,<unk>  disrupted the North American market for illegal drugs, capitalizing on pre-existing demand for opiates such as heroin and prescription pharmaceuticals. In 2016,<unk>  and<unk>  analogues were the most common cause of overdose deaths in the United States at more than 20,000, about half of all opioid-related deaths. Most of these overdose deaths were due to illegally-made<unk> . There is concern that the growing demand may prove highly attractive to organized crime and aspiring criminals, especially those operating in areas around the Golden Triangle in Southeast Asia, e.g. Shan State in Myanmar, where production of synthetic drugs has expanded dramatically since the late 2000s. Compared to heroin, it is more potent, has higher profit margins, and, because it is compact, has simpler logistics. It can be cut into, or even replace entirely, the supply of heroin and other opiates.
Fentanyl
Remifentanil
Ketamine
Alfentanil
Propofol
Etomidate
Sevoflurane
Methoxyflurane