And now, there's an effort to stop a powerful tranquilizer called "Tranq" from becoming a deadly street drug.
Jacqui Berlinn holds a photo of her son Corey. He's battling addiction on the streets of the Tenderloin and she's worried about "Tranq."
"He said whatever was in the drugs that he took made it so he just absolutely could not move his body," said Berlinn, co-founder, Mothers Against Drug Addiction and Deaths.
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Xylazine, also known as Tranq, is used by veterinarians to sedate large animals, and when mixed with already-powerful opioids... it's deadly.
"I believe Tranq is already on the street, unfortunately," she said.
It's been most pervasive in the northeast of the U.S., but the Drug Enforcement Administration warns Tranq is showing up more and more out west.
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Over a two-year period, the DEA's lab reports a more than 100% increase of xylazine in the illicit drug supply being snuck into deadly opioids like fentanyl.
"I just want to make sure that our city is set up to be monitoring for this and testing for it," said Supervisor Matt Dorsey.
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Dorsey wrote a letter to the medical examiner in support of its efforts to start testing overdose victims for xylazine this year.
"The work they are doing given the crisis we're facing is life-saving and we have to fight for this," said Dorsey.
And because it's not an opioid, an overdose caused by xylazine cannot be reversed by Narcan - the nasal spray relied on so heavily in saving lives.
"Narcan is deployed thousands of times a year citywide among the interventions that we count from first responders," he said.
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Making the tracking of Tranq that much more critical says the supervisor.
"God forbid if there's an addictive drug out there for which these interventions aren't going to work it's going to be terrifying," he said.
As for Jacqui, she's all for the medical examiner's move to test for Tranq. And if it's detected, she has a suggestion.
"Maybe put out public notices in some way to those on the streets so they know the supply is tainted with Tranq and protect themselves," Berlinn said.
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