2026 ICD-10-CM Diagnosis Code F59Unspecified behavioral syndromes associated with physiological disturbances and physical factors

ICD-10-CM CodesF01–F99F50-F59F59

ICD-10-CM F59
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

F59 is a billable ICD-10-CM diagnosis code for unspecified behavioral syndromes associated with physiological disturbances and physical factors. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). Coders also document this condition as behavioral syndrome associated with physiological disturbance and physical factors. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Miscellaneous mental and behavioral disorders/conditions.

Code Identity

ICD-10-CM Code
F59
Billable Status
Yes — Valid for Submission
Code Describes
Unspecified behavioral syndromes associated with physiological disturbances and physical factors
Chapter
F50-F59
Behavioral syndromes associated with physiological disturbances and physical factors

Code Classification

ChapterF01–F99Mental and behavioural disorders
SectionF50-F59Behavioral syndromes associated with physiological disturbances and physical factors
CategoryF59Unspecified behavioral syndromes associated with physiological disturbances and physical factors
This CodeF59Unspecified behavioral syndromes associated with physiological disturbances and physical factors

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Behavioral syndrome associated with physiological disturbance and physical factors

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Psychogenic physiological dysfunction NOS

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Dysfunction
      • physiological NEC
        • psychogenic
    • Dysfunction
      • psychophysiologic
    • Psychological and behavioral factors affecting medical condition

Clinical ClassificationClinical

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

CCSR MBD013
Miscellaneous mental and behavioral disorders/conditions
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Mental Disorders

Mental disorders (or mental illnesses) are conditions that affect your thinking, feeling, mood, and behavior. They may happen over a short period of time or come and go. Some can be chronic (long-lasting). They can affect your ability to relate to others and function each day..

The full article covers:

  • What are mental disorders?
  • What are some types of mental disorders?
  • What causes mental disorders?
  • Who is at risk for mental disorders?
  • How are mental disorders diagnosed?
  • What are the treatments for mental disorders?

Read the full article at MedlinePlus

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

Convert F59 to ICD-9-CMHistory

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

ICD-9-CM
306.8 Psychogenic disorder NEC
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 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About F59Overview

Is F59 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report unspecified behavioral syndromes associated with physiological disturbances and physical factors on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What is the ICD-9 equivalent of F59?

Under the General Equivalence Mappings, unspecified behavioral syndromes associated with physiological disturbances and physical factors converts to ICD-9-CM 306.8 (psychogenic disorder NEC). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.