Warning Letters — What to Expect
A warning letter is FDA's primary enforcement communication — it is public, searchable, and commercially significant.
What triggers a warning letter?
- Inadequate response to 483 observations
- Systemic MDR failures
- Off-label promotional claims
- Failure to submit required reports
Key facts
- Must respond in writing within 15 business days
- Published publicly on FDA's website
- Visible to customers, partners, and other regulators globally