Research
Approved, off-label, unapproved, compounded
Four words describe four different legal states, and sales copy treats them as one. The most common swap is calling a compounded peptide an off-label prescription, which is a phrase that needs an approved drug to mean anything.
Approved means one use was reviewed
Before a drug is approved, a company submits clinical data to FDA and has to show the drug is safe and effective for its intended uses. Safe does not mean without side effects; it means FDA determined the benefits outweigh the risks for that particular use.
What comes out the other side is narrow. Approval attaches to specific conditions, a specific form, and a specific population, and all of it is written into approved labeling that tells prescribers how to use the drug for that use.
Some compounds in this market do have an approved product behind them. Where one exists, the approval usually covers a narrow indication in a specific population, which is rarely the reason the compound is being offered.
Off-label is a decision about an approved drug
Once FDA approves a drug, a prescriber may generally use it for an unapproved purpose when they judge it medically appropriate. That is off-label use, and FDA gives three examples of what it covers.
A drug approved to treat one condition used for a different one. A drug approved as a capsule given as an oral solution. A drug approved at one dosing pattern used at another.
Every one of those examples starts from an approved product. Off-label describes a departure from the label, so it requires a label to depart from.
FDA is direct about the consequence: where a drug is used off-label, the agency has not determined that it is safe and effective for that use.
Unapproved new drug describes the product
This is a different kind of statement. It is about the product's legal status rather than about a prescriber's judgment.
The reasoning FDA applies runs in three steps, and an August 2026 letter to a peptide vial seller lays them out. A product is a drug when its labeling shows it is intended to diagnose, treat or prevent disease, or to affect the structure or function of the body. It is a new drug when it is not generally recognized as safe and effective under the conditions its labeling suggests. And a new drug cannot be shipped across state lines without an approved application in effect.
A product that fails all three is an unapproved new drug, and no prescription changes that. The status belongs to the product.
Note where the evidence in such a finding comes from. It comes from marketing copy, because intended use is established by what a seller says the product is for.
Compounded is a fourth state, and it is not approval
FDA states it plainly: compounded drugs are not FDA-approved, which means the agency does not verify the safety, effectiveness or quality of compounded drugs before they are marketed.
Compounding exists for a real reason. A patient allergic to a dye, or unable to swallow a tablet, may need a medication made differently. Compounders may also prepare versions of a drug on FDA's shortage list under conditions set in federal law.
A compounded drug is also not a generic. A generic is approved under its own section of the law and has to establish therapeutic equivalence to a brand-name product. A compounded preparation goes through none of that.
What federal law does control is the raw material. A pharmacy compounding under section 503A may use a bulk drug substance only if it meets a pharmacopeial monograph, is a component of an approved drug product, or sits on FDA's 503A bulks list.
Research use only is outside all four
A vial labeled for research use only is being sold as a laboratory chemical. It is not approved, not compounded under a prescription, and not dispensed by a pharmacy.
The label is a claim by the seller about intended use, and it does not settle the question by itself. FDA addressed that in an August 2026 letter to a peptide vial seller. Despite labeling products for research use only and not for human or animal consumption, evidence from the website established they were intended as drugs for human use.
So the disclaimer describes a supply channel rather than a legal shield. What a seller does elsewhere on the same site can contradict it.
The swap that happens most often
The sentence to watch for is some version of "prescribed off-label by a licensed clinician" attached to a compounded peptide.
For most compounds sold this way there is no approved product anywhere, so there is no label to be off. The prescription may be entirely lawful, and the phrase describing it is still wrong. What is happening is a prescription for a compounded preparation of an unapproved substance, which is a different thing with a different set of protections.
A second swap runs the other way. A compound with a real approval, for a narrow indication in a specific population, gets sold for something else while the approval does the persuading. The approval is real. It is also about a different use.
Neither swap is necessarily deliberate. Both change what a reader thinks has been reviewed.
Four questions that place any offer
Does an FDA-approved product containing this compound exist? If not, off-label is not the right description of anything on offer.
If one exists, is the use being sold the approved one? An approval for a narrow indication in a specific group is not support for a general wellness use.
Is what you would receive the approved product, or a compounded preparation? Those are different products with different oversight, and a provider naming its compounding pharmacy is answering the useful half of that question.
Is it being dispensed by a pharmacy against a prescription at all, or shipped as a research chemical? That distinction decides whether anything in the prescription drug supply chain applied to the vial.
Key takeaways
- Approval attaches to a specific use, form and population, and is written into approved labeling.
- Off-label means using an approved drug outside its label, so it requires an approved product to exist.
- Unapproved new drug is a status of the product, established partly from the seller's own marketing claims.
- Compounded drugs are not FDA-approved, and FDA does not verify their safety, effectiveness or quality first.
- A compounded preparation is not a generic; a generic is approved and must show therapeutic equivalence.
- A research-use-only label states an intended use and does not settle the legal question on its own.
Frequently asked questions
Can a compounded peptide be prescribed off-label?
The phrase does not fit. Off-label use means using an FDA-approved drug for a purpose outside its approved labeling, which requires an approved product to exist. Most compounded peptides have no approved product anywhere, so there is no label to depart from. A prescription for a compounded preparation is a different arrangement, and describing it as off-label implies a review that never happened.
Are compounded drugs approved by FDA?
No. FDA states that compounded drugs are not FDA-approved and that it does not verify their safety, effectiveness or quality before they are marketed. Compounding serves real needs, including patients who cannot use an approved product and drugs on the shortage list. It is a different regulatory arrangement from approval, not a lighter version of it.
Is a compounded drug the same as a generic?
No. A generic drug is approved by FDA under its own section of the law and must establish therapeutic equivalence to a brand-name product, among other requirements. A compounded preparation goes through no such review. The two get conflated because both are alternatives to a brand-name product, and the similarity ends there.
What makes a product an "unapproved new drug"?
Three findings together. The product is a drug, because its labeling shows it is intended to treat a condition or affect the structure or function of the body. It is a new drug, because it is not generally recognized as safe and effective under the conditions its labeling suggests. And no approved application is in effect for it. Intended use is established from marketing claims, which is why website copy is what gets quoted in such findings.
Does a research-use-only label keep a product outside drug law?
Not by itself. The label states an intended use, and FDA weighs it against the rest of the evidence. In an August 2026 letter to a peptide vial seller, the agency wrote that despite research-use-only and not-for-human-consumption labeling, evidence from the website established the products were intended as drugs for human use. It also noted the seller supplied bacteriostatic water, a peptide guide and a peptide calculator alongside them.
Sources
Each document below is named as it names itself, with the date printed on that document rather than the day it was read.
- Understanding Unapproved Use of Approved Drugs "Off Label" — U.S. Food and Drug Administration, February 2018
- Compounding and the FDA: Questions and Answers — U.S. Food and Drug Administration, September 2025
- Bulk Drug Substances Used in Compounding Under Section 503A of the FD&C Act — U.S. Food and Drug Administration, May 2026
- Warning Letter to Royal Peptides LLC, reference 734884, Center for Drug Evaluation and Research — U.S. Food and Drug Administration, August 2026