In the United States, compounding pharmacy standards hinge on whether compounding occurs under section 503A (state-licensed pharmacies and physicians) or section 503B (FDA-registered outsourcing facilities). That distinction determines whether USP chapters or federal CGMP rules apply, and it shapes who inspects the facility, how often, and what documentation proves compliance.
TL;DR:
- For 503A, verify an active state license and patient specific prescription records; for 503B, confirm FDA registration and review its CGMP records.
- USP chapters <795>, <797>, and <800> cover nonsterile, sterile, and hazardous drug compounding, but state adoption determines which version is enforceable locally.
- 503B facilities face risk based FDA inspections and must follow CGMP, report adverse events, and label products as compounded rather than claim FDA approval.
- Request the latest Form 483 and corrective action response, then check whether cited problems were resolved or repeated across later inspection cycles.
- For each lot, request a current certificate of analysis and confirm the bulk substance manufacturer is FDA registered; a certificate alone cannot verify provenance.
Table of Contents
- Regulatory framework: sections 503A and 503B of the FD&C act
- USP compounding standards: key chapters and operational impacts
- CGMP and outsourcing facilities: what FDA expects in practice
- Bulk drug substances and the bulks-list processes for 503A and 503B
- Inspections and enforcement: reading Form 483s, warning letters, and other signals
- Accreditation and state oversight: PCAB, NABP, and state boards
- Practical compliance checklist and evidence to collect
- Regulatory perspective on enforcement priorities and next steps
- FAQ
- Sources
- Finding personalized care that fits your standards
Regulatory framework: sections 503A and 503B of the FD&C act
Section 503A covers traditional, state-licensed pharmacies and physicians compounding for an identified patient based on a valid prescription. When conditions are met, these compounders are exempt from CGMP, new drug approval, and certain labeling requirements under the FD&C Act. Section 503B governs outsourcing facilities, which register with the FDA voluntarily, compound with or without prescriptions for office use, and must comply with CGMP and FDA reporting obligations even though they too are exempt from new drug approval and some labeling rules.
For regulators, the practical split is oversight authority: 503A pharmacies answer primarily to state boards of pharmacy, while 503B facilities register with and report to the FDA directly, per the FD&C Act provisions FDA applies to compounding. For clinicians sourcing compounded medications, including GLP-1 therapies, the sourcing facility's registration status changes who to contact when something goes wrong.
Documentation that proves status under each section includes:
- State pharmacy license current and in good standing for 503A operations.
- FDA outsourcing facility registration number and current listing for 503B facilities.
- CGMP compliance records for any 503B supplier, since this is not optional at that tier.
- Prescription-specific records confirming 503A compounding was patient-specific, not bulk office stock.
USP compounding standards: key chapters and operational impacts
Three USP general chapters anchor the technical side of compounding quality. <795> governs nonsterile preparations, <797> governs sterile compounding, and <800> addresses handling of hazardous drugs. Compounded Preparation Monographs supplement these with formulation-specific guidance. These chapters are developed by USP, and the current <797> revision became official on November 1, 2023, establishing updated environmental and personnel requirements for sterile compounding.
Enforceability is not automatic nationwide. USP sets an official date, but state boards decide when and how a chapter becomes binding in that state, so clinicians and regulators should confirm local adoption before assuming a chapter applies.
Chapter adoption timing matters more than most clinicians realize: a facility can be technically compliant with an older standard if its state has not yet adopted the current revision, which is why checking state board status is a distinct step from checking USP's own chapter text.
Operationally, these chapters drive:
- Personnel training and competency verification before staff compound sterile or hazardous preparations.
- ISO classification of cleanrooms and anterooms based on preparation risk category.
- Beyond-use dating (BUD) assigned according to sterility testing and storage conditions, not convenience.
- Sterility and endotoxin testing frequency tied to risk category under <797>.
CGMP and outsourcing facilities: what FDA expects in practice
CGMP compliance, governed by 21 CFR parts 210 and 211, applies to 503B outsourcing facilities and represents a materially higher bar than state-level 503A oversight. These regulations require documented quality systems covering equipment qualification, batch production records, environmental monitoring, and stability programs, not just competent technique at the bench.
FDA inspects state-licensed 503A pharmacies primarily for cause, but it inspects registered 503B outsourcing facilities on a risk-based schedule, according to FDA's compounding Q&A. That schedule means 503B facilities face recurring federal scrutiny even absent a complaint.
Common inspection findings that lead to Form 483 observations or warning letters include:
- Inadequate environmental monitoring in sterile compounding areas.
- Insanitary conditions documented during routine or for-cause inspections.
- Failure to meet 503B conditions, which can trigger loss of exemptions and FDA enforcement action.
Outsourcing facilities also carry unique obligations: mandatory adverse event reporting to FDA and labeling that discloses the product is compounded, not FDA-approved, a distinction worth repeating to prescribers who assume outsourcing facility registration equals product approval. It does not.
Bulk drug substances and the bulks-list processes for 503A and 503B
Acceptable bulk drug substances reach compounders through three paths, and the path matters for both 503A and 503B compliance:
- USP or NF monograph compliance, where the substance meets an official compendial standard.
- Status as a component of an FDA-approved drug, allowing its use in compounding under specific conditions.
- Inclusion on an FDA bulks list established by rule, built from nominated substances evaluated for characterization, safety, and evidence of effectiveness.
While permanent bulks lists remain under development, FDA maintains interim policies for substances pending final evaluation. Regulators and clinicians verifying a supplier's bulk substance should request a current certificate of analysis (COA) and confirm the substance was manufactured by an FDA-registered establishment. A COA without a traceable, registered manufacturer behind it is not evidence of anything. This provenance question comes up often with compounded tirzepatide and state-level rules that shift which bulk substances remain available.
Inspections and enforcement: reading Form 483s, warning letters, and other signals
Inspection posture differs sharply by compounder type. State-licensed 503A pharmacies are typically inspected by FDA only for cause, meaning a complaint or adverse event triggers the visit. Registered 503B outsourcing facilities sit on a risk-based inspection schedule, so recurring federal review is built into their registration status.
Across both tiers, recent FDA inspection records show recurring citation patterns:
- Environmental monitoring gaps, especially inadequate air or surface sampling in sterile suites.
- Aseptic technique failures identified during observed compounding.
- Insufficient written procedures governing cleaning, garbing, or batch records.
Pro Tip: Ask for the facility's most recent Form 483 and its corrective action response before asking about accreditation badges: a clean CAPA history after a cited deficiency tells you more about current compliance than any certificate on the wall.
Chronology matters. A single old 483 with documented corrective action looks very different from a pattern of repeat citations across multiple inspection cycles.
Accreditation and state oversight: PCAB, NABP, and state boards
PCAB accreditation and NABP programs are voluntary quality signals, not substitutes for FDA or USP compliance. Accreditation reviews typically verify documented SOPs, personnel training programs, and quality assurance systems against a defined standard, giving clinicians a faster way to screen compounders before deeper due diligence.
Accredited status is worth confirming directly rather than taking on faith, and our patient guide to PCAB accreditation walks through what the designation does and does not cover.
With the state board, verify:
- Current license status and any disciplinary history on file.
- State adoption status of the relevant USP chapter version.
- Scope of practice permitted under that state's compounding rules.
Practical compliance checklist and evidence to collect
A workable verification sequence for clinicians and regulators looks like this:
- Confirm registration status, 503A state license or 503B FDA registration, before anything else.
- Request current COAs for the specific lot, not a generic template document.
- Review environmental monitoring logs and recent sterility or assay test results.
- Check staff training records and SOPs covering the preparation type in question.
- Ask about adverse event reporting history and process.
Pro Tip: A COA is only as trustworthy as the lab behind it: confirm the testing lab's accreditation independently rather than accepting the compounder's description of it.
Our five-step safety checklist for compounded semaglutide walks through exactly this kind of supplier verification, and the same logic applies across any compounded GLP-1 or peptide product, which is how we structure sourcing review internally.
Regulatory perspective on enforcement priorities and next steps
FDA scrutiny of outsourcing facilities has intensified, with CGMP compliance now the clearest dividing line between compounders worth trusting and those worth investigating further. Regulators should prioritize environmental monitoring records and bulk substance provenance over accreditation badges alone and push for better state-FDA information sharing so a warning letter in one jurisdiction surfaces faster everywhere else.
— Flexible
This article is general information, not a substitute for advice from a qualified doctor. Consult a qualified healthcare professional about your own circumstances before acting on anything here.
FAQ
What are the regulations for compounding pharmacies in the United States?
Compounding pharmacies operate under section 503A or 503B of the FD&C Act, with 503A pharmacies overseen primarily by state boards and 503B outsourcing facilities registered with and inspected by the FDA. The applicable requirements, including whether CGMP applies, depend entirely on which section governs the facility.
What are the USP compounding standards?
USP compounding standards are general chapters, including <795> for nonsterile preparations, <797> for sterile preparations, and <800> for hazardous drugs, that set technical requirements for personnel, environments, and testing. State boards determine when each chapter version becomes enforceable locally, so adoption timing varies by state.
Are there any FDA approved compounding pharmacies?
No individual compounded drug is FDA-approved, and FDA registration of an outsourcing facility does not mean the agency has approved its products. Clinicians evaluating whether a compounded therapy or an FDA-approved alternative fits a patient can review our overview of FDA-approved weight loss medications for context.
What are the USP 797 compounding guidelines?
USP <797> governs sterile compounding and covers personnel garbing, environmental classification, cleaning schedules, and beyond-use dating based on preparation risk category. The current revision became official on November 1, 2023, and facilities must also confirm their state has adopted that version for it to be locally enforceable.
Finding personalized care that fits your standards
We built our wellness programs around the same verification instincts this guide describes: doctor-led oversight, transparent sourcing conversations, and clinical follow-through that does not stop at the first prescription. If sourcing uncertainty around compounded GLP-1 products has you weighing options, our GLP-1 Injection, GLP-1 Microdose, and Oral GLP · Liposomal plans pair medication with ongoing clinician access and free dietitian visits, with no membership fees and flexible cancellation built into every plan.
For patients specifically asking about maintenance dosing, our semaglutide injection maintenance dose page details how we structure that phase of care. Start your intake today and get matched with a clinician who can walk through your options directly.
For supply chain and ingredient verification practices that mirror what we described above, our partner's guide to supplement compliance processes covers COA review from the manufacturing side, useful reading for anyone evaluating a compounder's bulk substance paperwork.