Carfentanil

Carfentanil or carfentanyl is a structural analog of the synthetic opioid analgesic fentanyl. Short acting and with fast onset, it has, weight for weight, around one hundred times stronger effects than fentanyl and thousands of times stronger than heroin. It is more effective at reducing pain response in rats than any other opioid. Carfentanil or carfentanyl is a structural analog of the synthetic opioid analgesic fentanyl. Short acting and with fast onset, it has, weight for weight, around one hundred times stronger effects than fentanyl and thousands of times stronger than heroin. It is more effective at reducing pain response in rats than any other opioid. Carfentanil was first synthesized in 1974 by a team of chemists at Janssen Pharmaceutica which included Paul Janssen. The effects of carfentanil, including overdose, can be reversed by naloxone.