The FDA’s official registry of drugs currently in shortage, maintained under the Federal Food, Drug, and Cosmetic Act. When a drug appears on the shortage list, compounding pharmacies (both 503A and 503B) are permitted to compound copies of that drug—an exception to the normal rule that prevents compounding of commercially available products.

The drug shortage list became the most contentious regulatory issue in the peptide space when semaglutide and tirzepatide appeared on it due to manufacturing demand exceeding supply. Their presence enabled a massive compounding market. When these compounds are removed from the shortage list, the legal basis for most compounding ceases—a scenario that directly affects patient access, compounding pharmacy business models, and the broader peptide supply chain. The FDA’s shortage determinations are not permanent; they are updated as supply conditions change.