Warning Letter
What is Warning Letter?
An official FDA communication notifying a company of significant regulatory violations that require prompt correction.
Why does Warning Letter matter?
A Warning Letter is FDA's formal notice that a company has significantly violated FDA regulations. Unlike a Form 483 (which lists observations), a Warning Letter is an official agency position that violations exist.
Warning Letters are public documents — published on FDA's website — and signal serious compliance failures. They often follow unresolved 483 observations.
Receiving a Warning Letter can block new drug approvals, trigger import alerts, and invite Congressional scrutiny. Companies under Warning Letter must demonstrate corrective actions before FDA will consider lifting restrictions.
The letter typically gives 15 working days to respond with a corrective action plan.
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