2027 ICD-10-CM Diagnosis Code F43.0Acute stress reaction

ICD-10-CM Codes›F01–F99›F40-F48›F43

ICD-10-CM F43.0
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

F43.0 is a billable ICD-10-CM diagnosis code for acute stress reaction. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 880. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Trauma- and stressor-related disorders.

Code Identity

ICD-10-CM Code
F43.0
Billable Status
Yes — Valid for Submission
Code Describes
Acute stress reaction
Short Description
Acute stress reaction
Same as the full description in the CMS dataset.
Parent Code
F43
Reaction to severe stress, and adjustment disorders

Code Classification

ChapterF01–F99Mental and behavioural disorders
SectionF40-F48Anxiety, dissociative, stress-related, somatoform and other nonpsychotic mental disorders
CategoryF43Reaction to severe stress, and adjustment disorders
This CodeF43.0Acute stress reaction

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute fugue state due to acute stress reaction
  • Acute panic state due to acute stress reaction
  • Acute stress disorder
  • Acute stupor state due to acute stress reaction
  • Clouded consciousness
  • Combat fatigue
  • Crisis
  • Exhaustion delirium
  • Psychogenic fugue
  • Psychogenic fugue co-occurrent and due to stress reaction
  • Shell shock
  • Situational crisis
  • Stress and adjustment reaction
  • Stupor

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to F43.0: its own notes plus those printed at Chapter 5. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From Chapter 5 (F01-F99) Mental and behavioural disorders applies to 872 codes
  • disorders of psychological development

Applicable To

Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.

  • Acute crisis reaction
  • Acute reaction to stress
  • Combat and operational stress reaction
  • Combat fatigue
  • Crisis state
  • Psychic shock

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Chapter 5 (F01-F99) Mental and behavioural disorders applies to 872 codes
  • symptoms, signs and abnormal clinical laboratory findings, not elsewhere classified (R00-R99)

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name F43.0, its category, or a range that includes it.

Excludes1 2

These codes carry an Excludes1 note naming F43.0: they are not reported together with it, unless the two conditions are unrelated.

  • R53.8 Other malaise and fatigue
    combat exhaustion and fatigue (F43.0)
  • R57 Shock, not elsewhere classified
    psychic shock (F43.0)

Excludes2 2

These codes carry an Excludes2 note naming F43.0: its condition is not part of those codes, and both may be reported when the patient has both.

  • F41 Other anxiety disorders
    acute stress reaction (F43.0)
  • F93.0 Separation anxiety disorder of childhood
    nonpsychotic mental disorders (F40-F48) names F40-F48, which includes this code

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR MBD007
Trauma- and stressor-related disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Stress

Stress is how your brain and body respond to a challenge or demand. When you are stressed, your body releases certain hormones. Hormones are chemicals that travel in your bloodstream and control how different parts of your body work. The hormones that are released when you are stressed make you alert and ready to act.

The full article covers:

  • What is stress?
  • What causes long-term stress?
  • How can long term-stress harm my health?
  • How can I manage long-term stress?
  • When should I ask my health care provider for help with stress?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert F43.0 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
308.9 Acute stress react NOS
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About F43.0Overview

What is the ICD-10 code for acute stress reaction?

The ICD-10-CM code for acute stress reaction is F43.0 (sometimes written as F430). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is F43.0 (Reaction to severe stress, and adjustment disorders) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report acute stress reaction on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does F43.0 group to?

When acute stress reaction is the principal diagnosis on an inpatient stay, it groups to MS-DRG 880 (acute Adjustment Reaction and Psychosocial Dysfunction), which carries a relative weight of 0.9306. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of F43.0?

Under the General Equivalence Mappings, acute stress reaction converts to ICD-9-CM 308.9 (acute stress react NOS). The mapping is approximate, so confirm the match fits the documentation.