FDA’s April 1, 2026 reminder says that certain conditions must be met for compounded drugs to qualify for exemptions under sections 503A and 503B of the FD&C Act.
503A and 503B are not interchangeable
For 503A, FDA highlights individual-patient prescriptions and restrictions on regularly or inordinate-amount compounding of essentially copies of commercially available drugs. For 503B, use of bulk substances generally depends on the 503B bulks list or applicable shortage conditions.
FDA says tirzepatide and semaglutide are not currently on the 503B bulks list or the drug-shortage list in the cited update. The page retains older updates, so an earlier paragraph reporting a shortage must not be mistaken for the most recent status.
Compounded is not FDA approved
FDA separately explains that compounded GLP-1 drugs do not undergo its premarket review for safety, effectiveness and quality. Its safety page also states that retatrutide and cagrilintide cannot be used in compounding under federal law.
These are different questions: whether a branded product is approved, whether a shortage exists, whether a particular compounding exemption applies and whether a specific product is suitable for a patient. A single ‘legal or illegal’ label obscures those distinctions.
Evidence record
Event date: 2026-04-01. Source review: inherited source synthesis; not re-audited in this expansion. Editorial publication: 2026-10-29. Original source links below retain their publication dates. These dates are not interchangeable. This is targeted source synthesis, not an exhaustive archive or a qualified clinical/legal review.
Revision history
29 October 2026: migrated from the research edition, retaining source links and evidence qualifications; not re-audited in the current expansion. Report a proposed correction through Contact us; do not include patient data.