2026 ICD-10-CM Diagnosis Code F45.21Hypochondriasis

ICD-10-CM Codes›F01–F99›F40-F48›F45

ICD-10-CM F45.21
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

F45.21 is a billable ICD-10-CM diagnosis code for hypochondriasis. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). Coders also document this condition as cutaneous hypochondriasis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Somatic disorders.

Code Identity

ICD-10-CM Code
F45.21
Billable Status
Yes — Valid for Submission
Code Describes
Hypochondriasis
Short Description
Hypochondriasis
Same as the full description in the CMS dataset.
Parent Code
F45.2
Hypochondriacal disorders

Code Classification

ChapterF01–F99Mental and behavioural disorders
SectionF40-F48Anxiety, dissociative, stress-related, somatoform and other nonpsychotic mental disorders
CategoryF45Somatoform disorders
This CodeF45.21Hypochondriasis

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Cutaneous hypochondriasis
  • Fear of breast cancer
  • Fear of breast disease
  • Fear of eye disease
  • Fear of genital cancer
  • Fear of genital disease
  • Fear of sexual dysfunction
  • Fear of skin disease
  • Hypochondriasis
  • Illness anxiety disorder

Tabular List NotesGuidance

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

Inclusion Terms

  • Hypochondriacal neurosis
  • Illness anxiety disorder

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.

    • Disorder(of)
      • anxiety
        • illness
    • Disorder(of)
      • hypochondriacal
        • neurosis
    • Disorder(of)
      • identity
        • illness anxiety
    • Hypochondria, hypochondriac, hypochondriasis(reaction)
    • Neurosis, neurotic
      • hypochondriacal
    • Nosomania
    • Psychoneurosis, psychoneurotic
      • hypochondriacal

Clinical ClassificationClinical

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

CCSR MBD011
Somatic disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Hypochondriasis

    preoccupation with the fear of having, or the idea that one has, a serious disease based on the person's misinterpretation of bodily symptoms. (apa, dsm-iv)

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 F45.21 to ICD-9-CMHistory

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

ICD-9-CM
300.7 Hypochondriasis
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 F45.21Overview

Is F45.21 (Hypochondriacal disorders) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report hypochondriasis on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What is the ICD-9 equivalent of F45.21?

Under the General Equivalence Mappings, hypochondriasis converts to ICD-9-CM 300.7 (hypochondriasis). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.