ICD10

ICD-10 Code F43: Reaction to severe stress, and adjustment disorders

F43 is an ICD-10 diagnosis entry used to group records related to Reaction to severe stress, and adjustment disorders. You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen. ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Mental, Behavioral and Neurodevelopmental disorders (F01-F99).

Reviewed by HealthAssure Clinical TeamUpdated 21 May 2026

What is this code?

ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Mental, Behavioral and Neurodevelopmental disorders (F01-F99).

When is it used?

  • May be used when a clinician documents reaction to severe stress, and adjustment disorders in a patient's medical record.
  • May appear in hospital records, claims, referrals, and clinical documentation.
  • This code may act more like a grouping or parent code, so a more specific child code may be used in final documentation when available.

What it does not mean

  • A code alone does not explain severity, treatment plan, or outcome.
  • A medical code should not be treated as a substitute for a doctor's diagnosis or advice.
  • This entry may represent a broader category rather than the most specific billable code.

Code hierarchy

chapter
5Mental, Behavioral and Neurodevelopmental disorders (F01-F99)
block
F40-F48Anxiety, dissociative, stress-related, somatoform and other nonpsychotic mental disorders
currentF40-F48

Where you may see this code

You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen.

Coding guidelines

Compatibility

Legacy code aligns to an official FY 2026 category. Frontend should resolve to the official category page and surface the billable child codes.
Legacy codes
F43
Replacement codes
F43.0 — Acute stress reactionF43.9 — Reaction to severe stress, unspecified

Common synonyms

Reaction to severe stress, and adjustment disorders

Frequently asked questions

Code details

CodeF43
SystemICD10
Display nameReaction to severe stress, and adjustment disorders
ChapterMental, Behavioral and Neurodevelopmental disorders (F01-F99)
BlockAnxiety, dissociative, stress-related, somatoform and other nonpsychotic mental disorders

Flags

BillableNo
Valid clinical useNo

Source

SourceICD-10
Version2026-annual
Releaseannual
Year2026

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.