HB4166 amends Michigan’s Public Health Code to add xylazine to the state’s controlled-substance enforcement framework and to create specific offenses and penalties tied to its illicit use. The bill defines “licit use of xylazine” for approved veterinary, pharmaceutical, compounding, and other authorized purposes, and then prohibits manufacturing, delivering, possessing, or fraudulently obtaining xylazine for illicit use. It also updates related definitions so that xylazine is treated similarly to controlled substances in sections governing administration, delivery, dispensing, manufacture, possession, and drug paraphernalia.
The bill also revises Michigan’s drug-paraphernalia and nitrous-oxide provisions to include items designed for use with xylazine for illicit use, and it makes selling or offering such items a crime. In addition, it creates or updates penalty provisions for xylazine-related conduct in the manufacturing, possession, and fraudulent-obtaining sections, generally making xylazine offenses felonies with penalties up to five years’ imprisonment and fines up to $15,000, depending on the section violated. The bill preserves existing overdose-medical-assistance protections and probation-related provisions while extending them to incidents involving xylazine.
HB4166 would amend multiple sections of the Public Health Code, primarily MCL 333.7103, 333.7105, 333.7106, 333.7401, 333.7403, 333.7403a, 333.7451, 333.7453, and 333.7455, to expressly regulate xylazine alongside controlled substances. It would create new statutory definitions for “illicit use” and “licit use” of xylazine, add xylazine to prohibited conduct involving manufacture, possession, delivery, and fraud, and establish criminal penalties for xylazine-related violations. It would also broaden the definition of drug paraphernalia to cover items intended for xylazine use and update the nitrous oxide/paraphernalia sales offense to include xylazine-related paraphernalia.
The bill’s overall tone is punitive and enforcement-oriented, reflecting a legislative response to concerns about illicit xylazine use and its role in drug misuse. Because no committee transcripts or recorded votes were provided, there is no documented floor or committee debate to indicate broader bipartisan support or opposition. Based on the text alone, the bill appears designed to strengthen criminal penalties and clarify lawful medical and veterinary uses rather than to create a treatment-centered approach.
The main point of contention likely concerns whether xylazine should be treated like a controlled substance for criminal enforcement purposes, especially given its legitimate veterinary and pharmaceutical uses. Another likely issue is the breadth of the paraphernalia and sales provisions, which could affect retailers, distributors, and health-care or veterinary supply chains. The bill does include carveouts for authorized medical, veterinary, compounding, and research uses, but the expansion of felony penalties and the inclusion of xylazine in paraphernalia definitions could still raise concerns about overbreadth, enforcement discretion, and impacts on lawful users and businesses.