Comparison
Compounded vs commercially available
These are two different regulatory objects, and one state board defines them in exactly those terms: a "product" is a commercially manufactured dosage form "that has been evaluated for safety and efficacy by the United States food and drug administration," while a "preparation" is a drug compounded in a licensed pharmacy or healthcare facility. The boundary between them is not quality or ingredients. It is whether an application was reviewed and approved — and approval attaches to that product, not to the molecule inside it.
What is the actual difference between the two?
Whether an application was reviewed and approved. Not ingredients, not quality, not who made it.
Ohio's compounding rules define both objects in the same regulation, which is useful because it forces the distinction into a single sentence each. A "product" is "a drug in a commercially manufactured pharmaceutical dosage form that has been evaluated for safety and efficacy by the United States food and drug administration." A "preparation" is "a drug compounded in a licensed pharmacy or other healthcare-related facility."
FDA states the consequence flatly: "Compounded drugs are not FDA-approved. This means that FDA does not review these drugs to evaluate their safety, effectiveness, or quality before they reach patients." Approval attaches to a product with a defined formulation, process, labelling and applicant. It is not a property of a molecule and it does not travel to a different preparation containing the same active ingredient.
The comparison
| A compounded preparation | A commercially available product | |
|---|---|---|
| Regulatory object | A preparation compounded in a licensed pharmacy or healthcare facility | A manufactured dosage form evaluated by FDA for safety and efficacy |
| Pre-market review | None — both compounding provisions work by exempting it from the approval requirement | Reviewed and approved before marketing |
| Made for | An identified individual patient under § 353a, or supplied as stock under § 353b | The market generally |
| Manufacturing-practice regime | Exempted for a 503A pharmacy by § 353a; applies to a facility registered under § 353b | Applies |
| Basis of the date on the container | A beyond-use date assigned under the compendial chapter the state has adopted, for a 503A preparation | An expiration date which "shall be determined by appropriate stability testing" |
| May be made when the other exists | Only outside the essentially-a-copy restriction, or under its documented exception | Not applicable |
| Can be described as FDA-approved | No, in any circumstance | Yes, as to that product |
What does "commercially available" actually mean?
Not what it means in ordinary English — and this is the term people get wrong.
FDA's position is that "a drug is not considered to be commercially available if it is on FDA's drug shortages list and limitations on compounding essentially copies are not applicable in these circumstances." A product can be manufactured, approved and sitting on a shelf somewhere and still not be commercially available in the sense this doctrine uses, if it is on the shortage list.
That has a consequence people find counterintuitive: the same preparation can be inside the restriction one month and outside it the next, with nothing about the preparation having changed. When the shortage ends, the copy rule switches back on. It is a status of the approved product, checked at a moment in time, not a characteristic of the compounded one.
What is the essentially-a-copy test?
FDA states it as two limbs plus an exception.
A compounded drug product may be considered essentially a copy where it "has the same active pharmaceutical ingredient(s) (API) as the commercially available drug product in the same, similar or an easily substitutable strength," and where "the commercially available drug product can be used by the same route of administration (regardless of how it is labeled) prescribed for the compounded drug product." The exception is that this "is unless a prescriber determines and documents the compounded drug product contains a change that produces a significant difference from the commercially available drug product for an identified individual patient."
FDA has also put a figure on the strength limb in its own worked example, treating amounts "within 10% of the strengths of the respective commercially available drug products" as the same, similar or easily substitutable. The full doctrine, including how the exception is and is not satisfied, is set out at essentially a copy of a commercially available drug.
Does adding another ingredient move a preparation outside it?
Not by itself, and FDA's own illustration is a combination.
FDA's worked example of a potentially essentially-a-copy product is a compounded product combining an active ingredient with a second one, where both amounts sit within the strength band above and the route matches. The combination is the example of the problem, not the solution to it.
The point generalises. The test asks about the active ingredient, the strength band and the route. A formulation difference that does not change those three does not, on FDA's stated test, move the preparation outside the restriction — and a difference that does still has to run through the prescriber-determination exception if it is going to be relied on.
Who decides the exception applies?
The prescriber, in writing, for a named patient. Three constraints, all in the same sentence.
The determination is the prescriber's, so a pharmacy cannot make it on your behalf. It is documented rather than assumed. And it is made "for an identified individual patient," which means it is not a formulary position, a standing protocol, or a property of the product. A menu of pre-written reasons attached to an item does not satisfy any of the three; what it automates is the appearance of a determination.
If a supplier presents a formulation as pre-cleared under this route, the question to put back is who they say made the determination, for which patient, and where it is recorded.
Where does the outsourcing-facility route differ?
It has two independent gateways to a bulk substance, and only one of them involves shortages.
FDA states that outsourcing facilities "may not compound a drug product that includes a bulk drug substance unless" the substance appears on the 503B bulks list, "or the drug product compounded from such bulk drug substance appears on FDA's drug shortage list at the time of compounding, distribution and dispensing." Those are alternatives, and they move independently: a proposal to change the bulks list decides nothing about the shortage route, and a shortage ending decides nothing about the list.
Note the timing built into the second gateway. The drug must be on the list "at the time of compounding, distribution and dispensing" — three moments, not one. FDA has said it may act where a facility "continues to fill new orders after the approved drug is removed from FDA's drug shortage list."
What if the approved product was discontinued?
Then the restriction has much less to bite on, and FDA has said so in a footnote.
FDA has stated it "does not intend to take action against an outsourcing facility for failing to compound in accordance with section 503B(a)(5) if it fills orders for a compounded drug that is essentially a copy of an approved drug that has been discontinued and is no longer marketed." Where the approved product is not being marketed, the constraint is largely inapplicable.
This is worth separating from the shortage case even though the two feel similar. A shortage is a temporary status of a marketed product. A discontinuation is the product leaving the market. They are recorded in different places and they behave differently over time.
Is there a volume rule?
There is an enforcement position about volume, and it is not a classification.
FDA has stated that it does not intend to take action against a compounder for compounding a product that is essentially a copy "regularly or in inordinate amounts" where the compounder "fills four or fewer prescriptions of that compounded drug product during a calendar month."
That is a statement about what FDA intends to do, at a point in time, at a level of volume. It does not make the preparation something other than essentially a copy, and a page or a supplier that describes it as making a formulation permissible has changed the claim into one FDA did not make.
What is never true on either side?
That a compounded preparation is approved, endorsed or evaluated — and saying so has a codified consequence.
FDA's regulations provide that "any person who represents that a compounded drug made with a bulk drug substance that appears on this list is FDA approved, or otherwise endorsed by FDA generally or for a particular indication, will cause the drug to be misbranded" under the relevant provisions. That is codified regulation, not guidance.
The same applies to the entities. FDA has stated that "the FD&C Act does not establish an 'FDA-approved' or 'FDA-licensed' designation for pharmacies or outsourcing facilities." A supplier describing a preparation as a generic, as the same as an approved product, or as clinically equivalent to one, is making a claim FDA has specifically identified as improper.
How this comparison was made
From FDA's published statements and the codified text, plus one state rule that happens to define both objects.
The federal material is quoted from 21 U.S.C. §§ 353a and 353b, from 21 CFR 216.23 and § 211.137, and from FDA's own pages on compounding law, shortage-list compounding, 503B bulk substances and its running clarification of the copy policy. The definitions of "product" and "preparation" are quoted from Ohio Administrative Code 4729:7-2-01, used because it states both in one place, not because Ohio's position is special.
No manufacturer, pharmacy or outsourcing facility is named, assessed or ranked anywhere on this page, and nothing here asserts any entity's compliance status. The manufactured side is described only as the set of requirements compounding is exempted from, because a manufacturer's own obligations were not researched.
All statements are as of 29 August 2026. Shortage-list status is the one input here that can change without notice, and it should be checked rather than carried forward.
Where to go from here
The entity-level version of this comparison — what an outsourcing facility is, next to what a conventional manufacturer is — is at a 503B outsourcing facility and a drug manufacturer compared. The two compounding pathways are at 503A pharmacies and 503B outsourcing facilities compared, and the transaction-level question of stock against prescriptions is at office stock and patient-specific fulfilment compared.
If you want a preparation list checked against these boundaries before you order against it, you can apply for an account.