Compounding Explained · formblends network
How compounded GLP-1s and peptides are regulated: 503A versus 503B, what a compounding pharmacy may and may not do after the shortage resolutions, how to look up a pharmacy licence in every state, how to read a certificate of analysis, the PCAC bulks lists, and an FDA enforcement timeline with dates.
Interactive
Each runs in your browser, shows its formula, and prints a dated assumptions note. Nothing you type leaves the page.
Reading
Written for people doing the arithmetic themselves: where the mistakes happen, and how to check your own work.
Explainers
What sections 503A and 503B of the Food, Drug, and Cosmetic Act actually say, who inspects each kind of compounder, what each may ship and to whom, and why neither produces an FDA-approved drug.
Updated September 4, 2026
Explainers
The statutory phrase that separates lawful patient-specific compounding from copying an approved drug: the identical-or-nearly-identical test, the significant-difference exception, the four-prescriptions-a-month reading, and what a prescriber has to document.
Updated September 4, 2026
Explainers
When semaglutide and tirzepatide went on FDA's shortage list, when each came off, the October 2024 remand, the 60- and 90-day enforcement discretion windows, and the April 24, 2025 court decision that closed the semaglutide window early.
Updated September 4, 2026
Explainers
After the shortage resolutions: the three things FDA says 503A compounders can still do, the things they cannot, the tighter position for 503B facilities, and the questions that tell you which side of the line an offer is on.
Updated September 4, 2026
Explainers
A COA is a lab report for one lot. Here is what each section means, which tests matter for an injectable compounded drug, how to match the document to your vial, and the things a COA cannot tell you.
Updated September 4, 2026
Explainers
How a substance gets onto the 503A bulks list, what Category 1, 2 and 3 meant under the interim policy, which peptides FDA placed in Category 2 in 2023, which were later withdrawn, and what the July 2026 advisory committee did and did not decide.
Updated September 4, 2026
Browse
Every date on this site is taken from an FDA page, an FDA declaratory order, a warning letter, a Federal Register notice or a state board site, with the link and the date we checked it. Where FDA has not said something, we say so rather than fill the gap. Compounded drugs are not FDA approved, and nothing here changes that.
It does not rank or recommend pharmacies, it does not name pharmacies beyond what an FDA document names, and it does not give medical or legal advice. The vetting checklist tool tells you what to verify and where. Whether to proceed is a decision for you and a licensed prescriber.
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