News Animal ‘tranq’ xylazine is becoming a deadly threat. Here’s how the US is trying to stop it. April 12, 2023 Ken Alltucker, USA TODAY Comments Off on Animal ‘tranq’ xylazine is becoming a deadly threat. Here’s how the US is trying to stop it. President Biden's drug czar, Dr. Rahul Gupta, announces plans to stop the spread of deadly xylazine, a veterinary tranquilizer mixed with fentanyl.