Carfentanil is the most potent opioid used commercially,
10,000 times stronger than morphine. It is a version or analogue of fentanyl, the painkiller that most recently made headlines with its role in the death of pop star Prince
Carfentanil can slow breathing significantly. It's not approved for human use but is used commercially to sedate large animals, such as elephants. About 2 milligrams
can knock out a nearly 2,000-pound African elephant.
Many users may not know they are even taking the drug, officials have said, as dealers are cutting heroin with fentanyl analogues to give it a boost and stretch their supply.
Its potency is deadly, and it's causing concern for those fighting the heroin epidemic, as recent overdose outbreaks in Ohio, Indiana and Florida have been linked to the drug.
Public health warnings
In July, officials in Hamilton County, Ohio, issued a public health warning
(PDF) after seeing 35 overdoses, including six deaths, in a three-day period.
On Wednesday, authorities reported a spike in heroin overdoses, with 36 reports of overdoses and two deaths. According to CNN affiliate WCPO in Cincinnati
, one of the deaths was a man described as being in his 30s who died in the parking lot of a Rally's Hamburgers.
Police told WCPO that it appeared more than one dealer was involved in distributing the potent mix. Hamilton County Heroin Task Force Director Tom Synan added that almost all the recent overdoses are in the same area on the west side of Cincinnati, leading officials to suspect it's all the same batch. Cincinnati is in Hamilton County.
Synan said the county has seen close to 90 heroin overdoses since this weekend.
Hamilton County usually sees about 25 overdoses in an average week, so these numbers represent a huge increase.
"We do not know for sure, but we suspect the heroin is laced with carfentanil," says Synan
In Indiana, near the border with Ohio, there were 12 heroin overdoses and one death during the same time period on Tuesday, according to Seymour Police Chief Bill Abbott. A 52-year-old Jennings County woman died as a result of an overdose, Indiana State Police Sgt. Stephen Wheeles said.
All of the overdoses required the use of naloxone, Wheeles said, and some of those revived with the drug were as young as 16.
"Due to Tuesday's overdoses, our troopers and deputies with the Jennings County Sheriff's Department continually ran out of the drug and had to restock from the EMS personnel, hospital and the remaining doses we had at our post," Wheeles said.
It is not clear whether the Indiana and Ohio overdoses are connected, but officials are investigating the possibility.
This month, a seizure of carfentanil in Manatee County, Florida, coincided with an increase in overdose deaths there.
Little data to track the drug
The Drug Enforcement Administration does not track carfentanil cases separately. Most states flag a handful of fentanyl analogues in postmortem testing, but very few labs across the country are equipped to test for it or have any reference materials to help identify it. The University of Florida Forensic Toxicology Lab is currently developing a new test to identify the drug.
Like fentanyl, carfentanil is dangerous not just to users but to anyone who comes into contact with it. Grains of it can be absorbed through the skin or inhaled.
According to the DEA, most fentanyl analogues in the United States are being manufactured in China and transported through Mexico.