A Powerful New Drug Is Creating a βWithdrawal Crisisβ in Philadelphia NYT: Science By:Jan Hoffman and Hannah Yoon 15 December 2025 at 06:59 Medetomidine, a veterinary sedative, mixed into fentanyl has sent thousands to hospitals, not only for overdose but for life-threatening withdrawal. It is spreading to other cities. Β© Hannah Yoon for The New York TimesThe Temple University Hospital emergency entrance.