Notes from the Field: Investigation of Unapproved Botulinum Toxin Product Administered at a Medical Spa — Colorado, 2025–2026

What is already known about this topic? Use of counterfeit or unapproved botulinum neurotoxin (BoNT) can result in serious illness. What is added by this report? In 2026, a Colorado poison center report identified use of a BoNT product not approved by the Food and Drug Administration (FDA) at a medical spa; subsequent public health investigation revealed patient safety issues including adverse effects after administration of the unapproved product. What are the implications for public health practice? Persons should be encouraged to seek BoNT treatment only from licensed providers administering FDA-approved products. Public health investigations of reports of posttreatment adverse events are important to ensure compliance with regulations and patient safety. included inappropriate use of a preservative-containing diluent, use of single-dose vials for multiple patients, inadequate tem perature monitoring, and storage and use of reconstituted and unlabeled product past the beyond-use date** (1). The provider received a public health order to immediately stop using the unap proved products, and a formal complaint against the provider’s license was submitted to the Colorado Department of Regulatory Agencies. After initiation of the public health investigation, the provider reported ceasing use of the unapproved products. Preliminary Conclusions and Actions Three persons experienced transient neurologic symptoms after injections of an unapproved BoNT product by a licensed provider in Colorado. The clinical features reported included both adverse reactions listed on the package insert of the product and reactions that were not listed on the package insert. Based on findings from the site investigation, poten tial causes include unknown product concentration, product ** Investigations of adverse events after BoNT administration have noted numerous deviations from FDA recommendations for drug dose, dilution, handling, injection site, and storage. contamination, improper preparation, and improper adminis tration or storage of the product (1). This response highlights the importance of communication and collaboration among poison centers, health care providers, and public health authori ties in reporting patients with symptoms after receiving BoNT injections (FDA | MedWatch Online Voluntary Reporting Form 3500). Follow-up public health investigations are impor tant to ensuring regulatory compliance and patient safety. In addition to being subject to other federal laws and regulations, medical spas might be regulated as dispensers under the Drug Supply Chain Security Act (DSCSA).†† On April 1, 2026, FDA issued a warning letter to a medical spa in Texas for obtaining botulinum toxin product in violation of DSCSA. In Colorado, administering non–FDA-approved products can be grounds for disciplinary action against a licensed provider by the Department of Regulatory Agencies, the state’s agency responsible for licensing professionals. BoNT purchased from an unauthorized supplier might not be FDA approved and might be counterfeit, contaminated, improperly stored, or otherwise unsafe (5). Persons should be encouraged to seek treatment only from licensed provid ers administering FDA-approved BoNT product