The FDA has issued an alert to healthcare professionals warning about the risks of patients being exposed to xylazine, a veterinary sedative, in illicit drugs. The alert states that xylazine has been found in counterfeit versions of opioid drugs and other illicit substances, and can lead to serious side effects such as respiratory depression, coma, and death. This is noted by resistance to Narcan reversal of suspected fentanyl overdose, necrotic skin ulcerations, and non- detection on routine toxicology tests. The FDA advises healthcare professionals to be aware of the potential for xylazine exposure in patients who have taken illicit drugs, and to report any adverse events related to xylazine to the FDA.