Off-Label Use
Off-label use is a clinician's prescription of an approved drug for an indication, population, dose or route outside its approved labelling, which is lawful practice even though promoting it is not.
FDA approves products, not the practice of medicine. Once a drug is approved for anything, a licensed prescriber may use it for another indication, age group, route or schedule, and nothing in the Act forbids it. The asymmetry is that the manufacturer may not promote those uses, because promotional claims outside the label can render the product misbranded for lacking adequate directions for its intended use. Courts have narrowed how far that restriction reaches against truthful, non-misleading speech, but it remains the core of the distinction.
The evidence behind off-label prescribing spans an enormous range. At one end are uses supported by large randomised trials whose sponsor never sought a label change, and recognised by the compendia payers use for coverage. At the other are uses supported by habit alone. Semaglutide is the familiar case: it was prescribed for weight reduction on its diabetes label before a separate obesity indication was approved, so the molecule moved from off-label to on-label with no change in its pharmacology.
The consequences are practical. Off-label use shifts justification onto the prescriber, who carries the consent and monitoring burden without the label's dosing, contraindication and adverse-reaction framework. Reimbursement often turns on compendial listing rather than the label, and liability analysis asks whether the use matched accepted practice, not whether it was on-label.
The error worth naming is misapplication of the term. Off-label use requires an approved product, so a compound approved nowhere cannot be used off-label, and describing BPC-157 that way borrows legitimacy the category does not extend. The mirror error treats off-label as a synonym for unsupported, when some off-label uses rest on better evidence than some approved ones.