December 12, 2017
I’m a great painkiller, but I can also kill you.
What molecule am I?
Image of Fentanyl 3D Image of Fentanyl

Fentanyl is a potent, and now notorious, opioid painkiller. As much as 100 times more potent than morphine, it acts quickly, but it remains in the body for only a short time, which is why it is usually administered in a patch.

Fentanyl is an agonist of μ-opioid receptors, which control pain but also can cause euphoria and lead to addiction. It is the most widely used synthetic opioid and is on the World Health Organization’s List of Essential Medicines.

In 1959, Belgian physician Paul Janssen and co-workers at his pharmaceutical company, Janssen Pharmaceutica, synthesized fentanyl as one in a series of opioid painkillers. In the 1990s, the company introduced the fentanyl patch.

Fentanyl is a key player in the current opioid abuse epidemic in the United States. It is so potent that people who deal with overdose victims and drug dealers must wear personal protective equipment to avoid exposure to the drug. To assist these responders, manufacturers of analytical equipment have developed detection devices that rapidly detect fentanyl and other narcotics without opening containers of the drugs

MOTW update: December 25, 2017

Fentanyl is a potent painkiller and one of the main culprits of the current opioid abuse epidemic in the United States. On December 13, 2017, as part of the effort to keep illicit fenanyl out of the country, US Customs Border Protection seized ≈35 kg of the drug at the San Ysidro, CA, port of entry. This quantity surpassed the previous record confiscation of ≈30 kg.

Fentanyl fast facts

CAS Reg. No.437-38-7
Molar mass336.47 g/mol 
AppearanceWhite crystals or powder 
Melting point87.5 ºC
Water solubility200 mg/L

MOTW update: 
July 15, 2019

Fentanyl is a widely abused opioid painkiller. The opioid antidote naloxone is not completely effective against overdoses of fentanyl and its companion drug carfentanyl; but recently Kim D. Janda and colleagues at the Scripps Research Institute (La Jolla, CA) developed monoclonal antibodies that blunt the effects of these drugs by sequestering them in the bloodstream.

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