The grey market refers to products sold outside a manufacturer's authorized distribution channels, without necessarily being illegal or counterfeit. In the GLP-1 space, this includes semaglutide or tirzepatide sourced from unregulated online sellers, overseas suppliers, or research-chemical vendors, rather than a licensed pharmacy or a compounding pharmacy operating within legal bounds. Grey market products carry meaningful risk: no guarantee of purity, correct dosing, sterility, or that the product is what it claims to be, and no pharmacist or prescriber oversight. This is distinct from legitimate compounded medications, which come from licensed, regulated compounding pharmacies.