It's killed thousands of people around the world and now Fentanyl has been detected in New Zealand's illicit drug market for the first time.
Know Your Stuff is an organisation that provides free drug testing at festivals and detected the controversial painkiller at an unnamed festival in February.
The owner of the white powder thought it was heroin, and while they're both opioids, Fentanyl is considerably more toxic and is more likely to lead to a fatal overdose.
Know Your Stuff director Wendy Allison said Fentanyl suppresses breathing at a much smaller quantity than other opioids.
"The risk of death is higher than other opioids, and further increased when unknowingly consumed as a substitute or adulterant in other drugs."
"We strongly recommend that users of opioids do not take Fentanyl, and any opioid should be tested for Fentanyl contamination before use," Ms Allison said.
In December, a coroner linked the controversial drug to the death of a 24-year-old in Whanganui after he suffered a shoulder injury in a quad bike accident last year.
The American singer Prince was also killed by the drug in 2016.
Chairman of the Health Quality and Safety Commission's opioid expert advisory group, Doctor Alan Davis told 1 NEWS Fentanyl is a "very potent drug".
"It's 25 to 50 times the potency of morphine," Dr Davis said.
The Health Quality and Safety Commission found that for every 1,000 people, two are being prescribed Fentanyl by a doctor.
"I'm not surprised but it is something we want to keep a very close eye on and particularly understand why it is being used in such a variable way," Dr Davis said.
KnowYourStuffNZ has put forward three recommendations to the Government to reduce the risk from Fentanyl:
1. Updating the Misuse of Drugs Act to empower DHBs and other drug health services to provide forensic drug checking in New Zealand cities, allowing people to identify if their substance is not what they expected. For example, testing by KnowYourStuffNZ in January identified n-ethylpentylone being sold as MDMA. February's mass hospitalisation in Christchurch due to n-ethylpentylone could have been prevented had such a service been widely available.
2. Facilitating the distribution of emergency overdose kits containing Naloxone, a very effective antidote to opioid overdose, to users of opioid drugs and their loved ones. Naloxone is affordable, easy to use, and legal as part of an approved emergency overdose kit. However an emergency kit has yet to be assembled or approved by the government. As yet Naloxone is only available on prescription through paramedics or emergency departments at hospitals. Most overdoses happen in front of other people and deaths are avoidable if Naloxone is readily available.
3. Implementing an effective drug Early Warning System. KnowYourStuffNZ's discovery of Fentanyl as a substitute in the illicit market demonstrates that the risks from new substances can be foreseen and reduced. In contrast, the mass hospitalisation incident in Christchurch and the 20 deaths associated with AMB-FUBINACA last year, show the damage that occurs without a warning system.