For the first time in U.S. history, a new drug has been designated as an "emerging threat" Xylazine has been used by veterinarians as a sedative and painkiller for over 50 years in the United States.

But this tranquilizer has been diverted from its use for 20 years to become the "tranq drug" 100 times stronger than morphine, it causes a drop in blood pressure, breathing and heart rate. It is also called the "zombie drug" because of the gaping wounds it causes on the skin.