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Nov 10, 2023Nov 10, 2023

Isotonitazene, also called nitazene or ISO, is as dangerous as fentanyl, according to the DEA. (Image courtesy DEA)

by: Amy Larson

Posted: Feb 7, 2023 / 07:07 PM PST

Updated: Feb 15, 2023 / 01:27 PM PST

SAN FRANCISCO (KRON) — As San Francisco public health officials struggle to stem the tide of fentanyl, a new wave of deadly synthetic opioids is flooding into street drug scenes on the East Coast and Midwest.

New street drugs, including Tranq and ISO, are infiltrating illegal drug markets. San Francisco leaders say it's likely only a matter of time before these drugs reach the Bay Area, and a tragic new chapter of the city's overdose crisis will begin.

Supervisor Matt Dorsey sent a letter to the Chief Medical Examiner's Office on Tuesday seeking to ensure public health officers are prepared to monitor and track newly emerging drugs.

Dealers mix ISO, Tranq, and fentanyl into a wide range of street drugs. "With all the synthetic drugs out there, and the way they’re being mixed together, you never know what you’re actually buying," warned DEA Intelligence Analyst Maura Gaffney.

Isotonitazene, also called nitazene, or ISO, is as dangerous as fentanyl, according to the DEA.

"A drug that was never approved for medical use, nitazines are being sourced from China and being mixed into other drugs," the DEA wrote. "In powder form, ISO can appear yellow, brown, or off-white in color. DEA regional forensic laboratories have seen this drug mixed into heroin and/or fentanyl, and marketed as common street drugs, with deadly consequences. However, in other parts of the country, ISO has already been seen pressed into counterfeit pills and falsely marketed as pharmaceutical medication."

Tranq, also known as Xylazine, is an animal tranquilizer used for large livestock. "Xylazine is a non-opiate sedative, analgesic, and muscle relaxant only authorized in the United States for veterinary use according to the U.S. Food and Drug Administration," DEA officials wrote.

In a December 2022 report, the DEA reported that Tranq has been detected in a growing number of overdose deaths.

"If you have an opioid and a sedative, those two things are going to have stronger effects together," Chelsea Shover, an epidemiologist at UCLA, told KHN. Narcan, an opioid overdose reversal medication, would not be able to save someone who overdosed with Tranq, experts say.

Supervisor Dorsey said the Chief Medical Examiner's Office serves an essential role saving lives of San Franciscans struggling with substance use disorders. The supervisor described the city's opioid epidemic as "a public health calamity that far surpasses COVID-19 and is historically unprecedented since the deadliest days of the AIDS crisis."

Dorsey said rapid and reliable testing and reporting of new drugs emerging in the city is critical.

Overdoses are currently the leading cause of preventable death among people ages 18 to 45 in America, outpacing deaths from car crashes and suicides, according to the CDC.

In San Francisco last year, 620 people died from drug overdose deaths, with 72 percent attributed to fentanyl, according to city data.

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