Poison and drug information centers at the University of Arizona and Banner, along with Arizona Public Health and Safety Agencies, are warning health care providers of high concentrations of fentanyl found in illicit drugs, especially cocaine.

The warning was prompted by a cluster of recent cases involving higher concentrations of the deadly synthetic opioid and requiring multiple doses of naloxone to treat.

Sari Horwitz led The Washington Post’s “Opioid Files” series. In a February webinar, she described fentanyl as driving a rising trend of mass poisonings.

“Several people at a gathering — who are using cocaine, meth, heroin, oxycodone, Xanax, Adderall, all kinds of different things — don’t realize that what they're using is laced with fentanyl, and they all die,” she said.

At the same event, Magdalena Cerdá, director of the Center for Opioid Epidemiology and Policy at NYU Grossman School of Medicine, said only 15% of U.S. counties have community-based Naloxone distribution programs, and less than 50% have treatment centers that provide the overdose medicine.

“So, essentially, broad swaths of the United States lack access to some of the leading sources of naloxone for community based use,” said Cerdá.

The agencies encourage medical providers and labs to report relevant results to the Arizona Poison System at 800-222-1222.