As the legal and regulatory battle over compounded GLP-1s intensifies, the FDA has been building a parallel public health case based on real-world harm data. The numbers are striking: as of early 2025, the agency had received more than 455 adverse event reports linked to compounded semaglutide and more than 320 tied to compounded tirzepatide.
The most common category of adverse event was dosing error. Compounded GLP-1s were typically dispensed in multi-dose vials rather than the single-dose auto-injectors used for branded products. Patients self-administering from these vials frequently miscalculated their doses — in some cases administering ten times the intended amount. Many required hospitalisation.
The API supply chain is the deeper problem. At peak demand in 2023 and 2024, some compounding operations sourced active pharmaceutical ingredients from suppliers that had not been verified by US regulatory authorities. In September 2025, the FDA launched a global “green list” import alert designed to identify and block GLP-1 API from unverified foreign sources — a signal that the agency had credible evidence of counterfeit or substandard ingredients entering the compounding supply chain.
The FDA also issued warning letters to websites selling products labelled “for research use only” that were being purchased and self-injected by consumers. These products, which include peptide analogues of GLP-1 medications, exist entirely outside the regulatory framework and have no safety data whatsoever.
For South African patients considering purchasing compounded or “research grade” GLP-1 products online, the safety picture is clear: the risks are real, documented and potentially serious. The absence of a regulatory framework equivalent to the FDA’s in South Africa means that patients here have even less protection if something goes wrong.
Sources
- FDA. Adverse event reports: compounded semaglutide and tirzepatide. As of early 2025
- Pharmacy Times. FDA Moves to Permanently Close the Door on Compounded GLP-1s. June 2026
- FDA. Global import alert: GLP-1 active pharmaceutical ingredients. September 2025