How to Prepare for an FDA Inspection: Complete Readiness Guide
- Beng Ee Lim
- 14 hours ago
- 20 min read
FDA inspects medical device manufacturers to verify compliance with 21 CFR Part 820 quality system requirements, using a structured approach often associated with the QSIT inspection method. Inspections can be routine surveillance or for-cause, such as follow-up to significant complaints, recalls, or other risk signals. Plan 8–24 weeks to get inspection-ready by closing CAPA gaps, organizing DHF and DMR records, confirming complaint handling, and running a mock audit. During the inspection, assign an escort, keep a document request log, provide what is requested, and document everything said and promised. If you receive an FDA Form 483, FDA encourages a written response within 15 business days with corrective actions and supporting evidence.
This guide shows you how to prepare for FDA inspections 3-6 months in advance, what FDA actually looks for, how to handle investigators during the inspection, and how to respond to 483 observations to avoid escalation to Warning Letters.
What Triggers an FDA Inspection
FDA inspections are not truly “random,” but they can feel that way because FDA uses risk-based scheduling plus event-driven inspections.
Trigger 1: Routine Surveillance Inspection (Post-Market)
When it happens:
FDA conducts routine inspections as part of its ongoing surveillance program. Timing is risk-based, not fixed.
Factors FDA uses to prioritize surveillance inspections:
Device risk class (Class III prioritized over Class II)
Time since last inspection
History of 483s or Warning Letters
Volume and severity of complaints and MDRs
Recall history
Whether the firm is a first-time manufacturer
Scope:
Typically a broad Quality System inspection following FDA’s QSIT framework:
CAPA
Design controls (DHF)
Production and process controls (DMR)
Complaint handling
Management responsibility
Notice:
Often unannounced. FDA may arrive during normal business hours without prior warning.
On-site duration:
Usually 2–7 business days, depending on company size and complexity.
Trigger 2: For-Cause Inspection
When it happens:
Initiated after FDA identifies a specific risk signal suggesting potential noncompliance or safety issues.
Common triggers include:
Patterns of serious MDRs (injury or death)
Class I or Class II recalls
Failure to adequately address complaints
Whistleblower reports or anonymous tips
Media or public reporting of device safety concerns
Follow-up to adverse inspection history
Scope:
Focused on the specific issue that triggered the inspection, but FDA will expand scope if systemic problems are uncovered.
Risk level:
High. For-cause inspections have a significantly higher likelihood of Form 483 observations and Warning Letters.
Trigger 3: Follow-Up Inspection
When it happens:
After a previous inspection resulted in:
Form FDA 483 observations, or
A Warning Letter
Purpose:
Verify that corrective and preventive actions were:
Implemented
Effective
Sustained over time
Timeline:
Typically 6–12 months after the prior inspection, but can occur sooner if FDA is concerned.
Consequence of failure:
Escalation to Warning Letter, injunction, consent decree, or product seizure.
Trigger 4: Pre-Market Inspection (Selective)
When it happens:
FDA may conduct a pre-market inspection before clearing certain submissions, but this is not routine for most 510(k)s.
More likely when:
Manufacturer is first-time registrant
Device is novel or higher risk
Manufacturing process is complex or unproven
FDA has prior concerns about quality system maturity
Scope:
Focused on:
Design controls
Manufacturing readiness
Quality system implementation
Impact:
If significant deficiencies are identified, FDA can delay clearance until issues are resolved.
Trigger 5: Program-Based or International Inspections
Examples:
FDA participation in MDSAP audits
Foreign manufacturer inspections coordinated with international regulators
Note:
MDSAP does not eliminate FDA oversight, but it can influence inspection planning and reduce duplicative audits in some cases.
Bottom line: Most companies will be inspected within 2-5 years of starting operations. Preparation should start 3-6 months before you expect inspection, not when FDA shows up.
What FDA Actually Inspects: The QSR (21 CFR Part 820)
FDA inspections evaluate compliance with the Quality System Regulation (QSR) under 21 CFR Part 820, using the QSIT (Quality System Inspection Technique) framework. While FDA is transitioning to the Quality Management System Regulation (QMSR) aligned with ISO 13485, current inspections still reference Part 820.
FDA does not inspect everything equally. Certain subsystems receive significantly deeper scrutiny due to their impact on patient safety and product quality.
1. Management Controls (21 CFR 820.20, 820.25)
What FDA looks for:
Quality policy established and communicated
Management reviews conducted at defined intervals
Evidence leadership reviews quality metrics, complaints, CAPA, audits
Adequate resources allocated to the quality system
Common findings:
Missing or outdated management review records
Reviews held but required inputs not covered
Quality policy exists but employees are unaware of it
2. Design Controls (21 CFR 820.30)
One of the most heavily scrutinized areas
What FDA looks for:
Complete and current Design History File (DHF)
Defined design inputs and outputs
Verification tied directly to design inputs
Validation using production-equivalent units
Risk management integrated throughout development
Controlled design changes
Formal design reviews
End-to-end traceability (requirements → design → verification → validation)
Common findings:
DHF incomplete or fragmented
Verification performed before design freeze
Design validation missing or insufficient
Informal design changes without change control
No traceability between requirements and tests
Risk analysis not updated after changes
Why this matters:
Design control deficiencies are consistently among the most common and most serious FDA inspection findings.
3. Document and Change Controls (21 CFR 820.40)
What FDA looks for:
Documented document control procedures
Current documents available at point of use
Obsolete documents removed
Impact assessments performed before changes
Common findings:
Obsolete procedures still in use
Changes implemented before approval
No documented rationale or impact assessment
Missing revision histories
4. Purchasing Controls (21 CFR 820.50)
What FDA looks for:
Approved supplier list
Supplier qualification and evaluation records
Purchasing specifications defined
Receiving acceptance activities documented
Common findings:
Unqualified suppliers
Incomplete receiving inspection records
Supplier performance not monitored
5. Production and Process Controls (21 CFR 820.70, 820.75)
What FDA looks for:
Accurate Device Master Record (DMR)
Clear manufacturing procedures
Process validation where required
Equipment calibration and maintenance
Sterilization validation (if applicable)
Common findings:
DMR does not match actual practice
Validation missing or outdated
Calibration overdue
Operators deviating from procedures
6. Acceptance Activities (21 CFR 820.80, 820.86)
What FDA looks for:
Defined acceptance criteria
In-process and final inspections performed
Records demonstrating acceptance activities
Appropriate statistical methods (if used)
Common findings:
Incomplete inspection records
Undefined acceptance criteria
Skipped inspections without justification
7. Nonconforming Product (21 CFR 820.90)
What FDA looks for:
Identification and segregation of nonconforming product
Investigation and documented disposition
Justification for rework or use-as-is decisions
Common findings:
Nonconforming product not segregated
No root cause analysis
Unjustified use-as-is dispositions
8. Corrective and Preventive Action (CAPA) (21 CFR 820.100)
Consistently one of FDA’s highest-risk focus areas
What FDA looks for:
CAPA system capturing issues from all sources
Meaningful root cause analysis
Corrective actions addressing root causes
Preventive actions where appropriate
Effectiveness checks
Timely closure
Common findings:
CAPA backlog
Superficial root cause analysis
No effectiveness verification
Complaints not feeding into CAPA
9. Labeling and Packaging Controls (21 CFR 820.120, 820.130)
What FDA looks for:
Controls preventing label mix-ups
Label approval and issuance records
Packaging validation for sterile barriers
Common findings:
Obsolete labels not destroyed
Inadequate label control procedures
Incomplete package validation
10. Handling, Storage, and Distribution (21 CFR 820.140–160)
What FDA looks for:
Appropriate storage conditions
Shelf-life validation
Distribution and lot traceability records
Common findings:
No shelf-life data
Environmental controls missing
Incomplete traceability
11. Records, Installation, and Servicing (21 CFR 820.170, 820.180, 820.200)
What FDA looks for:
Complete Device History Records (DHRs)
Installation and servicing records (if applicable)
Records legible and retrievable
Common findings:
Missing or incomplete DHRs
Illegible records
Service records not maintained
12. Complaint Handling (21 CFR 820.198)
Another top inspection priority
What FDA looks for:
All complaints captured and documented
Investigation decisions justified
Timely investigations
MDR reporting compliance
Linkage to CAPA when appropriate
Common findings:
Verbal complaints not recorded
Delayed or missing investigations
MDR-reportable events not reported
No complaint-to-CAPA linkage
13. Internal Audits (21 CFR 820.22)
What FDA looks for:
Periodic internal audits
Qualified, independent auditors
Documented findings
Corrective actions taken
Common findings:
Audits skipped or superficial
Same auditor reviewing own work
Audit findings not addressed
FDA Inspection Reality
FDA consistently prioritizes design controls, CAPA, and complaint handling because failures in these areas are most likely to result in unsafe devices reaching patients. These subsystems account for the majority of serious inspection observations across the industry.
Pre-Inspection Preparation (3-6 Months Before)
Don't wait for FDA to show up. Prepare as if inspection could happen tomorrow.
Step 1: Conduct Internal Mock Audit (Month 1-2)
Hire external consultant or use internal auditor to simulate FDA inspection
Scope: Full QSR audit (all subsystems)
Approach: Use FDA inspection checklist (based on QSIT - Quality System Inspection Technique)
Deliverable: List of gaps, non-compliances, recommendations
Cost: $15K-$40K (external consultant) or internal resource time
Value: Identifies issues before FDA does. Mock audits typically find 20-50 gaps that need fixing.
Step 2: Create Inspection Readiness Plan (Month 1)
Document: Prioritized list of gaps with owners and deadlines
Prioritization:
Critical (fix immediately): Design control gaps, CAPA backlog, complaint investigation delays, missing MDR reports
High (fix before inspection): Document control issues, procedure gaps, training deficiencies
Medium (address if time): Minor documentation improvements, procedural refinements
Assign owners: Each gap assigned to specific person with deadline
Track progress: Weekly reviews in management meetings
Step 3: Fix CAPA Backlog (Month 1-3)
Goal: All CAPAs current or with documented justification for delays
Actions:
Review all open CAPAs (sort by age)
CAPAs >90 days old: Close if addressed, or document reason for delay
CAPAs >365 days old: Priority closure or escalate
For each CAPA verify: root cause analysis performed, corrective action implemented, effectiveness check completed
Target state: <10 overdue CAPAs, none >180 days without justification
Resource needed: 1-2 people dedicated 2-3 months
This is #1 inspection failure area. FDA will scrutinize CAPA system heavily.
Step 4: Organize Design History Files (Month 1-3)
Goal: Complete, organized DHF for each device
Actions:
Create DHF checklist: design inputs, outputs, verification, validation, risk analysis, design reviews, design transfer
For each device, assemble DHF contents
Identify gaps (missing documents)
Recreate or document why missing (if legacy device, may need to justify based on pre-QSR manufacturing)
Organize electronically (indexed, searchable) or physically (tabbed binders)
Common gaps:
Design inputs not documented (verbal requirements not written down)
Verification performed before design freeze
Design validation missing production-equivalent units
Risk analysis not updated for design changes
No traceability matrix
Resource needed: 1-2 people dedicated 2-4 months depending on number of devices
This is #2 inspection failure area.
Step 5: Clean Up Complaint System (Month 1-2)
Goal: All complaints investigated timely, MDRs filed appropriately
Actions:
Review all open complaints >30 days
Complete pending investigations
Determine if MDR reportable (death, serious injury, malfunction that could cause death/serious injury)
File overdue MDRs immediately (better late than never)
Update procedures to prevent future delays
Red flags FDA looks for:
Complaints marked "pending" for months
Pattern of not investigating complaints
MDR reportable events not reported
Resource needed: 1 person dedicated 1-2 months
This is #3 inspection failure area.
Step 6: Update and Review Procedures (Month 2-3)
Goal: All QSR procedures current, accurate, and followed
Actions:
Review each QSR procedure (last revision date, relevance)
Update outdated procedures
Verify procedures match actual practice (walk the floor)
Remove obsolete procedures from circulation
Train employees on updated procedures
Common issues:
Procedures written years ago, never updated
Actual practice differs from written procedure (dangerous - FDA sees non-compliance)
Obsolete procedures still accessible
Resource needed: Quality team 1-2 months
Step 7: Train Employees (Month 3-4)
Goal: All employees trained on relevant procedures, aware of inspection protocol
Training topics:
GMP/QSR basics: Why we have procedures, importance of following them
Their specific procedures: How to do their job per SOPs
Inspection protocol: How to interact with FDA investigators (covered below)
Documentation practices: Complete records, legible, accurate
Special focus: Production operators, QA staff, engineers, management
Training records: Document all training (attendees, date, topics, trainer)
Resource needed: 2-3 weeks for training sessions + record-keeping
Mock Q&A sessions: Practice answering FDA questions ("What do you do if you find a nonconforming part?")
Step 8: Organize Records and Documents (Month 3-5)
Goal: Any document FDA requests can be retrieved within 15 minutes
Actions:
DHF: Organized by device, indexed
DMR: Current, matches actual process
DHR: Batch records complete, filed systematically
CAPA records: Organized, searchable by number
Complaint records: Filed by complaint number, indexed
Training records: Employee files with all training documented
Calibration records: Equipment list with current calibration status
Validation records: Process validation, sterilization, software, etc.
Create index/database: Allows quick retrieval
Physical location: Centralize records or know exactly where they are
Worst case scenario: FDA asks for document, you can't find it → automatic 483 observation
Step 9: Facility Walkthrough and Cleanup (Month 5-6)
Goal: Facility looks professional and organized
Actions:
Manufacturing floor: Clean, organized, procedures posted, obsolete materials removed
Storage areas: Labeled, organized, environmental monitoring current (if required)
Laboratories: Calibrated equipment, clean, procedures available
Quality area: Organized records, functional computer systems
Remove: Anything FDA shouldn't see (personal items, obsolete materials, non-conforming product if not properly segregated)
First impressions matter: FDA forms opinion based on initial walkthrough
Step 10: Conduct Final Mock Inspection (Month 6)
Goal: Simulate actual FDA inspection
Process:
Hire consultant or use internal auditor
Unannounced walkthrough (mimic FDA arrival)
Document requests (mimic FDA record review)
Employee interviews (mimic FDA questions)
Identify remaining gaps
Fix gaps immediately
Cost: $10K-$25K
Value: Final dress rehearsal, identifies any remaining issues
Total preparation cost: $50K-$150K (consulting, employee time, remediation)
Total preparation time: 3-6 months intensive effort
Alternative cost if unprepared: $200K-$1M+ (failed inspection, Warning Letter response, production delays)
During the Inspection: Best Practices
FDA investigators arrive. What do you do?
Day 1: Opening Meeting
What happens:
Investigators present credentials (Form FDA 482 - Notice of Inspection)
State purpose of inspection
Request to see facility
May request specific records immediately
Your actions:
✅ DO:
Verify credentials (check badges, write down names)
Accept Form FDA 482 (you must allow inspection)
Offer conference room for investigators
Assign dedicated escorts (2 people minimum who will stay with investigators entire time)
Take notes of all requests and conversations
Be professional, courteous, cooperative
❌ DON'T:
Refuse inspection (FDA has authority)
Appear defensive or hostile
Volunteer information not requested
Make promises you can't keep ("we'll have that for you in 30 minutes" then take 4 hours)
Allow investigators to roam unescorted
Assign Escorts (Critical)
Role of escort: Stay with FDA investigators at all times, facilitate requests, document everything
Qualifications:
Primary escort: Quality manager or VP Quality (knows systems intimately)
Secondary escort: Operations manager or engineer (knows manufacturing)
Backup escort: For when primary unavailable
Escort responsibilities:
Accompany investigators everywhere
Take detailed notes (what they review, what they ask, what you provide)
Coordinate document requests
Answer questions (if they know answer) or find subject matter expert
Flag any concerns to management immediately
Why this matters: Unescorted investigators may observe things out of context, talk to employees unprepared, or misinterpret situations.
Document Requests
FDA will request many documents: DHF, DMR, CAPA records, complaint files, procedures, training records, calibration records, audit reports, management review records
Your response process:
✅ DO:
Write down exact request: "Investigator requested DHF for Device Model X, all design verification test reports"
Acknowledge and set timeframe: "We'll retrieve that and have it available within 30 minutes"
Retrieve ONLY what was requested: Don't provide extra documents
Log what you provided: Document request log (date, time, what requested, what provided, who provided)
Make copies: Keep copy of everything you give FDA (you'll need it for 483 response)
❌ DON'T:
Provide documents not requested ("here's some related info too")
Provide incomplete records ("we're still looking for the rest")
Provide draft documents (only final approved documents)
Guess if you don't know ("I think it's in this folder")
Employee Interviews
FDA will interview employees: Operators, QA staff, engineers, managers
Preparation (before inspection):
Train employees on how to answer questions:
✅ DO:
Answer only the question asked (don't elaborate)
If you don't know, say "I don't know, but I can find out"
Be honest (lying to FDA = federal crime)
Refer to procedures if uncertain ("let me check the SOP")
Stay calm and professional
❌ DON'T:
Guess or speculate
Volunteer information not asked
Badmouth company or coworkers
Discuss problems or complaints casually
Say "we usually do it this way" if procedure says otherwise (indicates not following procedures)
Example good answers:
FDA: "What do you do if you find a defective part?"
Employee: "I follow our nonconforming material procedure, SOP-QA-005. I tag the part, move it to the nonconforming area, and fill out a nonconformance report."
Example bad answers:
Employee: "Oh, it depends. Sometimes I just throw it away if it's obvious. If it's borderline I might ask my supervisor."
(This indicates: not following procedures, inadequate controls, inconsistent handling)
Facility Walkthroughs
FDA will tour manufacturing, QA, labs, storage areas
What they're looking for:
Cleanliness and organization
Procedures posted and current
Operators following procedures
Environmental monitoring current (if required)
Equipment calibrated (check stickers)
Nonconforming product properly segregated
No obvious safety or quality hazards
Your escort's role during walkthrough:
Explain what's happening in each area (briefly)
Answer questions about processes
Note anything FDA takes particular interest in
Redirect if investigator trying to access areas not relevant
Red flags FDA notices:
Disorganized, dirty facility
Operators not following visible procedures
Expired calibration stickers on equipment
Nonconforming product mixed with good product
Safety hazards
Daily Debriefs (Internal)
End of each day: Management team debriefs
Topics:
What did FDA review today?
What questions did they ask?
Any concerning areas?
What documents requested for tomorrow?
Any corrective actions needed overnight?
Purpose: Stay ahead of issues, coordinate response, identify patterns in FDA's focus
Closing Meeting (Final Day)
What happens:
FDA presents Form FDA 483 (inspectional observations) if deficiencies found
Or FDA issues "No 483" (clean inspection)
Investigators explain each observation
You have opportunity to respond or clarify
Investigators leave
Your actions:
✅ DO:
Listen carefully to each observation
Take detailed notes
Ask clarifying questions ("can you show me the specific record you're referencing?")
Acknowledge factual observations
Provide context if appropriate (not excuses)
Thank investigators for their time
❌ DON'T:
Argue or get defensive
Make promises about corrective actions without thinking through
Sign anything except acknowledging receipt of 483
Dismiss observations as minor
Understanding 483:
483 observations = violations of QSR
Each observation cites specific regulation violated (e.g., 21 CFR 820.100)
Observations range from minor documentation gaps to serious quality failures
Number of observations doesn't directly correlate to severity (1 serious observation worse than 5 minor ones)
Inspection duration: Typically 3-7 days depending on facility size and scope
Common FDA 483 Observations (And How to Avoid)
Based on FDA public data, these are the most frequent 483 observations:
Observation #1: Inadequate CAPA System (21 CFR 820.100)
Typical wording: "The firm failed to establish and maintain procedures for implementing corrective and preventive actions. Review revealed [X] CAPAs overdue for closure, some open for more than [Y] days."
Examples:
47 CAPAs overdue, some >365 days
No root cause analysis documented (says "operator error" without investigation)
No effectiveness checks performed
CAPA system not capturing issues from all sources (complaints ignored)
How to avoid:
✅ Address CAPA backlog before inspection (<10 overdue)
✅ Document root cause analysis for every CAPA (5 Whys, fishbone, etc.)
✅ Perform effectiveness checks after corrective action implemented
✅ Link complaints to CAPA when appropriate
✅ Establish preventive actions proactively
Why this is #1: FDA sees CAPA as foundation of quality system. Broken CAPA = broken quality system.
Observation #2: Inadequate Design Controls (21 CFR 820.30)
Typical wording: "The firm failed to maintain a DHF for each device type. Design [inputs/outputs/verification/validation] could not be located or were incomplete."
Examples:
DHF doesn't exist ("it's scattered across emails and laptops")
Design verification performed before design frozen (backwards process)
Design validation missing or insufficient (tested 2 units, not production equivalent)
No traceability from requirements to verification tests
Design changes made without formal change control
How to avoid:
✅ Create complete DHF for each device (assembled, indexed)
✅ Document design inputs clearly (written requirements)
✅ Freeze design BEFORE verification testing
✅ Perform design validation with production-equivalent units
✅ Create traceability matrix (requirements → design → verification → validation)
✅ Control all design changes formally
Observation #3: Inadequate Complaint Handling (21 CFR 820.198)
Typical wording: "The firm failed to investigate complaints. Review revealed [X] complaints marked 'pending investigation' for more than [Y] days with no documented rationale."
Examples:
23 complaints pending >180 days
Verbal complaints not documented
Investigations not performed (complaint closed without investigation)
MDR reportable events not reported to FDA
No linkage between complaints and CAPA
How to avoid:
✅ Document ALL complaints (including verbal)
✅ Investigate complaints timely (<30 days)
✅ Determine MDR reportability within 30 days
✅ File MDRs when required
✅ Link significant complaints to CAPA
✅ Close complaint investigations with documented rationale
Observation #4: Process Validation Inadequate (21 CFR 820.75)
Typical wording: "The firm failed to establish and maintain procedures for validating device design and manufacturing processes. Process validation for [X] was inadequate."
Examples:
Process validation not performed (jumped to production)
Validation insufficient (only 1 run instead of 3 consecutive successful runs)
Validation outdated (performed 10 years ago, process changed since)
Revalidation not performed after process changes
How to avoid:
✅ Perform process validation before routine production (IQ/OQ/PQ)
✅ Three consecutive successful validation runs
✅ Revalidate after significant process changes
✅ Document validation rationale, protocols, results
Observation #5: Inadequate Document Control (21 CFR 820.40)
Typical wording: "The firm failed to establish and maintain procedures to control documents. Obsolete procedures [X] were found at point of use."
Examples:
Obsolete procedures still in use on manufacturing floor
Current procedures not available to employees
Changes implemented before change control approval
No document revision history
How to avoid:
✅ Remove obsolete documents from use (physically remove)
✅ Ensure current procedures available at point of use
✅ Control changes formally (change control board approval before implementation)
✅ Maintain document revision history
Observation #6: Equipment Calibration Overdue (21 CFR 820.72)
Typical wording: "The firm failed to ensure equipment is calibrated per established schedules. Equipment [X] last calibrated [date], overdue by [Y] months."
Examples:
Calibration stickers expired
No calibration schedule established
Calibration records incomplete
Out-of-spec equipment not evaluated for impact on product
How to avoid:
✅ Establish calibration schedule for all equipment
✅ Track calibration due dates (calendar reminders)
✅ Calibrate before due date
✅ Investigate if equipment out-of-spec (were products affected?)
Observation #7: Training Records Incomplete (21 CFR 820.25)
Typical wording: "The firm failed to establish and maintain procedures for training. Training records for [employees] were incomplete or not current."
Examples:
Employees performing tasks without documented training
Training records missing
Training outdated (GMP training 3 years ago, nothing since)
No verification of training effectiveness
How to avoid:
✅ Train all employees on procedures relevant to their role
✅ Document all training (date, attendees, topics, trainer signature)
✅ Annual refresher training
✅ Verify effectiveness (e.g., quiz, observation)
Other common observations: Nonconforming product control, supplier qualification, DHR completeness, management review gaps, internal audit deficiencies
Responding to FDA 483 Observations
You received a Form 483. What you do next matters.
Timeline: 15 Business Days (FDA Expectation)
FDA does not legally require a written response to a Form 483, but FDA strongly encourages firms to respond in writing within 15 business days of the inspection close.
Why responding matters:
Demonstrates commitment to compliance
Reduces risk of escalation to a Warning Letter
Documents your corrective actions in the FDA record
Sets the tone for your ongoing relationship with the reviewer
Best practice: Always respond. Silence is interpreted as indifference.
How FDA Evaluates Your Response
FDA does not just check whether you “answered.” They evaluate whether your response shows:
Understanding of the issue
Root cause thinking (not surface fixes)
Systemic correction, not one-off cleanup
Credible timelines
Objective evidence
A weak response often leads to follow-up questions or escalation.
Required Elements of an Effective 483 Response
For each observation, your response should include the following six components.
1. Acknowledgment
Acknowledge the observation factually and professionally.
Do not argue the finding or minimize it.
Example:
“We acknowledge that at the time of the inspection on [date], the firm had 47 CAPAs overdue for closure, some exceeding 365 days without documented justification.”
2. Root Cause Analysis
Explain why the issue occurred.
Use a structured method such as 5 Whys or fishbone analysis.
What FDA expects:
System causes, not individual blame
Clear linkage between cause and corrective action
❌ Avoid: “Operator error,” “oversight,” “isolated incident”
✅ Use: Resource gaps, process failures, lack of escalation, inadequate oversight
3. Immediate Corrections (Already Completed)
State what you did immediately to address the specific finding.
Include:
Specific actions
Dates completed
Current status
This shows FDA the issue is under control now, not just planned.
4. Long-Term Corrective Actions (System Fixes)
Describe the systemic changes you are implementing to prevent recurrence.
Examples:
SOP updates
New escalation thresholds
Additional resources
Training programs
Management review changes
System or tooling improvements
FDA is far more interested in this section than the immediate fix.
5. Effectiveness Checks
Explain how you will verify the corrective actions worked.
Be concrete:
What metric will be monitored?
How often?
For how long?
What is the acceptance criterion?
Example:
“CAPA aging will be reviewed monthly for six months. Target: fewer than 10 open CAPAs, none exceeding 90 days.”
6. Completion Timeline
Provide realistic timelines for actions not yet completed.
❌ Don’t promise 30 days if the work will take 90
✅ Credibility matters more than speed
FDA understands remediation takes time. Unrealistic promises hurt trust.
Example: Strong 483 Response Structure
FDA Observation:
“The firm failed to establish and maintain procedures for implementing corrective and preventive actions per 21 CFR 820.100. Review revealed 47 CAPAs overdue for closure, some open for more than 365 days.”
Acknowledgment
We acknowledge that at the time of the inspection on [date], 47 CAPAs were overdue for closure without documented justification.
Root Cause Analysis
A 5 Whys analysis identified the following root causes:
Insufficient staffing dedicated to CAPA management
No formal escalation process for overdue CAPAs
CAPA metrics not reviewed in management review meetings
Immediate Corrections (Completed)
Assigned two additional quality engineers to CAPA closure on [date]
Reviewed all 47 overdue CAPAs:
23 closed after verification
18 documented with justified delays
6 prioritized and closed by [date]
Long-Term Corrective Actions (In Progress)
Revised CAPA SOP to include escalation thresholds (>60 days to QA Manager, >90 days to VP Quality)
Implemented CAPA aging dashboard
Added CAPA metrics to monthly management review
Trained quality staff on revised procedure
Effectiveness Check
CAPA aging metrics will be reviewed monthly for six months. Acceptance criteria: fewer than 10 open CAPAs, none exceeding 90 days. First review scheduled for [date].
Attachments
Revised CAPA SOP
CAPA dashboard screenshot
Training records
What NOT to Include
❌ Denials of factual findings
❌ Blaming individuals
❌ Excuses (“we were understaffed”)
❌ Vague promises (“we will improve”)
❌ Arguments with the inspector
FDA is not interested in winning a debate. They are evaluating control.
Who Should Write and Approve the Response
Primary owner: QA leadership
Contributors: SMEs, Regulatory, Manufacturing
Recommended: Regulatory consultant review for complex findings
Approval: CEO or President signature shows management commitment
Cost Reality
Typical ranges (varies widely by scope and severity):
Internal effort: 40–80 hours
Consulting support: $15K–$50K
Corrective action implementation: $5K–$100K+
Total typical cost: $20K–$150K
Escalation to a Warning Letter multiplies these costs significantly.
What Happens After Submission
FDA may:
Accept the response and take no further action
Ask follow-up questions
Escalate to a Warning Letter if response is inadequate or violations are serious
Goal: Resolve at the 483 stage. Escalation becomes public and far more costly.
Practical Tip
Strong 483 responses are evidence-driven, not narrative-driven.
Having CAPA records, DHF traceability, training logs, and change history already organized makes the difference between a smooth close and months of follow-up.
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Critical Takeaways
Prepare 3–6 months before an expected inspection.
Conduct a mock audit, reduce CAPA backlog, organize DHF and DMR, and clean up complaint handling.
Typical prep cost: $50K–$150K.
Cost of a failed inspection: $200K–$1M+ in remediation, delays, and lost credibility.
CAPA, design controls, and complaints drive ~70% of 483s.
Focus preparation disproportionately on these three areas. This is where FDA spends the most time.
Assign dedicated FDA escorts.
Investigators should never be unaccompanied. Escorts coordinate requests, control document flow, and log everything FDA asks for and receives.
Answer only what is asked.
Do not volunteer information or provide extra documents “just in case.” Train employees to answer concisely and factually.
Always respond to a Form 483 within 15 business days.
Include acknowledgment, root cause analysis, immediate corrections, long-term corrective actions, effectiveness checks, and realistic timelines.
Demonstrate systemic improvement, not cleanup.
FDA is not impressed by fixing one instance. They want evidence that the underlying system has been corrected.
Do not argue with FDA observations.
Acknowledge factual findings. Provide context if needed, but do not deny, debate, or make excuses.
Warning Letters are public and serious.
They affect customers, partners, and investors. A strong 483 response is your best chance to prevent escalation.
Mock audits typically uncover 20–50 gaps.
External consultants are especially valuable because they see issues internal teams have normalized.
Document everything during the inspection.
Maintain a real-time log of requests, documents provided, verbal comments, and investigator concerns. This log becomes essential when drafting your 483 response.
Frequently Asked Questions
Can FDA inspect without notice?
Yes. Post-market surveillance inspections are often unannounced and can occur during normal business hours. Pre-approval inspections may include advance notice. FDA has inspection authority under FD&C Act Section 704, and you cannot refuse entry.
What if I cannot find a document FDA requests?
Be honest. Say, “We’re locating that document and will provide it as soon as possible.”
Do not claim a document exists if it does not. Failure to produce requested records is a common and avoidable 483 observation. This is why document organization before inspection is critical.
Can I refuse to show FDA certain areas of my facility?
No. FDA has authority to inspect all areas related to device manufacturing and quality systems. Refusal can be considered obstruction and may result in an inspection warrant.
How long do I have to respond to a Form 483?
There is no legal deadline, but FDA strongly expects a response within 15 business days. Timely responses demonstrate accountability and significantly reduce enforcement risk.
What if I disagree with a 483 observation?
If FDA observed it, it happened. You may provide clarification or context, but outright denial usually escalates issues. The safer approach is acknowledgment followed by corrective action.
Will FDA make my 483 public?
Yes. Form 483s are public records available through FOIA. Warning Letters are proactively posted on the FDA website. This is why a professional, evidence-based response matters to customers and investors.
What is the difference between a Form 483 and a Warning Letter?
Form 483: Inspection observations identifying deficiencies
Warning Letter: Formal enforcement action indicating serious or unresolved violations
Warning Letters are public and signal potential escalation to seizures, injunctions, or consent decrees if issues persist.
How often will FDA inspect my facility?
Typically:
Class II manufacturers: Every 2–5 years
Class III manufacturers: About every 2 years
Frequency increases with recalls, MDR trends, or prior compliance issues. For-cause inspections occur outside routine schedules.
Can FDA inspect my suppliers?
Yes. FDA may inspect suppliers as part of your inspection or independently. Regardless, you are responsible for supplier quality, even if FDA has never inspected them.
What if FDA finds product that does not meet specifications?
At minimum, expect a 483 for inadequate controls. If there is patient risk, FDA may detain or seize product. You must assess distributed product impact and initiate recalls if necessary.
Do I need a lawyer present during an FDA inspection?
Not required. Legal counsel can be helpful for high-risk situations, but overt legal obstruction can raise red flags. Most inspections are best managed by trained quality and regulatory personnel.
What happens if I receive a Warning Letter?
You must respond comprehensively, usually within 15 business days. FDA may reinspect to verify corrective actions. Failure to remediate can lead to consent decrees, import detention, or injunctions.
How do I know if my corrective actions are adequate?
FDA ultimately decides during follow-up review or inspection. Best practice is to have an experienced regulatory consultant review your response and verify implementation internally before claiming completion.