Carfentanil: the White House drug threat notice, and Philadelphia’s numbers
Everything I said in this afternoon's video, and where each number came from. The national figures are from a White House drug threat notice dated September 15, 2026. The Philadelphia figures are the city health department's own drug-checking reports, current through June 2026.
The notice
“There is an elephant tranquilizer contaminating the illicit drug supply that's a hundred times stronger than fentanyl, and it's hit every state except South Dakota and Hawaii.”
The White House Office of National Drug Control Policy published a Drug Threat Notice on September 15, 2026. It names three fentanyl analogues, carfentanil, fluorofentanyl and methylfentanyl, as the greatest current threat from fentanyl analogues "due to their lethality and prevalence across the nation." Its words on reach: carfentanil and fluorofentanyl "were each detected in every state except South Dakota and Hawaii in 2025," from DEA lab data. Its words on strength: carfentanil is "100x more powerful than fentanyl." The White House release calls it an elephant tranquilizer; it was sold from 1986 as Wildnil to immobilize deer, elk and moose, was used on elephants in zoo practice, and production stopped in 2003.
ONDCP Drug Threat Notice, Sept 15 2026 (PDF)White House releaseAVMA: Wildnil history
“Made in illegal labs and smuggled in, mostly inside fentanyl, and samples are up more than 200% since 2024.”
The notice: traffickers "continue to produce these illicit substances and smuggle them into the United States as counterfeit prescription pills or in powder form, to be added to other drugs." It names no country; DEA's 2025 threat assessment says Mexico has been the main source of illicit fentanyl and its analogues since about 2019, with precursor chemicals mostly from China. "Mostly inside fentanyl" is the CDC's finding: in deaths where carfentanil was found, illegally made fentanyl was there too 87% of the time. And the 200%: the notice reports "carfentanil samples increasing by 206%" in 2025 lab testing versus 2024.
Same noticeDEA 2025 National Drug Threat Assessment (PDF)CDC MMWR, Dec 2024: carfentanil in overdose deaths
Philadelphia
“In Philly, it went from almost none to 1 in 4 bags in six months.”
The city checks street drug samples every quarter. In samples where the main drug was heroin or fentanyl, carfentanil was in 1 of 313 from January to June 2025, about 1 in 5 from July to September, and 24%, about 1 in 4, from October to December. "Bags" is my shorthand; these are drug-checking submissions, not a count of every bag in the city. One thing I didn't have time to say: it has since fallen, to 11% in early 2026 and 7% by June. That is the point. The supply changes faster than any warning can, in both directions. Every carfentanil-positive sample the city has found also contained fentanyl.
Philadelphia Department of Public Health health update, Nov 13 2025 (PDF)PDPH drug checking, Oct to Dec 2025PDPH drug checking, Apr to Jun 2026
The test strip
“A fentanyl test strip won't catch it. The strip can tell you fentanyl is in the bag. It can't tell you what's hiding behind it.”
Philadelphia's health department: "there is no validated drug testing strip for carfentanil." In lab testing of the two main strip brands, fentanyl triggered the strip at 200 nanograms per milliliter and carfentanil only at 2,000, ten times the concentration, and sensitivity drifts between manufacturing lots. Carfentanil is present in trace amounts, so a strip is unlikely to react to it. The strip will still turn positive, because the fentanyl it is mixed into is there. That is all the strip is telling you.
PDPH on test stripsHarm Reduction Journal, 2023: strips tested against 251 opioidsHarm Reduction Journal, 2024: strip performance by lot
If you want to do something about it
I sit on the advisory board of End Overdose, a national nonprofit that has worked since 2018 to end drug-related overdose deaths through education, medical intervention and public awareness. They run a free online course that teaches you to recognize and respond to an overdose, and they get naloxone and fentanyl test strips to people who need them at no cost. The course takes less time than it took you to find this page.
What I left out
Deaths. The notice says the three analogues together were involved in at least 12,500 deaths since 2023, but its own breakdown is carfentanil nearly 600, fluorofentanyl nearly 12,000, methylfentanyl about 50. Overdose deaths overall are falling: down 12.3% nationally in the 12 months ending March 2026, and Philadelphia's 2025 count of 921 is its first year under 1,000 since 2016. This is a story about what is in the supply, not a death surge. For clinicians, the notice's hospital line: standard opioid urine screens do not detect fentanyl analogues, and "carfentanil will not be detected" by fentanyl screens either; a negative screen in someone who clearly overdosed is not reassurance.
CDC provisional overdose death countsInquirer, May 2026: Philadelphia 2025 countONDCP notice, hospital guidance
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Every number on this page links to where it came from. If I got one wrong, tell me and I'll correct it here.
Rick Pescatore, DO
I'm an emergency physician, the editor-in-chief of Emergency Medicine News, and a former chief physician for Delaware's Division of Public Health. I founded BellyMD to work on the gut-brain problems medicine tends to wave off.