2026 ICD-10-CM Diagnosis Code G11.5Hypomyelination - hypogonadotropic hypogonadism - hypodontia

ICD-10-CM Codes›G00–G99›G10-G14›G11

ICD-10-CM G11.5
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

G11.5 is a billable ICD-10-CM diagnosis code for hypomyelination - hypogonadotropic hypogonadism - hypodontia. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). Coders also document this condition as 4H leukodystrophy. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Any dental condition including traumatic injury, Disorders of teeth and gingiva, and Nontraumatic dental conditions.

Code Identity

ICD-10-CM Code
G11.5
Billable Status
Yes — Valid for Submission
Code Describes
Hypomyelination - hypogonadotropic hypogonadism - hypodontia
Short Description
Hypomyelination - hypogonadotropic hypogonadism - hypodontia
Same as the full description in the CMS dataset.
Parent Code
G11
Hereditary ataxia

Code Classification

ChapterG00–G99Diseases of the nervous system
SectionG10-G14Systemic atrophies primarily affecting the central nervous system
CategoryG11Hereditary ataxia
This CodeG11.5Hypomyelination - hypogonadotropic hypogonadism - hypodontia

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • 4H leukodystrophy
  • Hypomyelination, hypogonadotropic hypogonadism, hypodontia syndrome

Tabular List NotesGuidance

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

Inclusion Terms

  • 4H syndrome
  • Pol III-related leukodystrophy

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.

    • Hypomyelination - hypogonadotropic hypogonadism - hypodontia
    • Leukodystrophy
      • pol III-related
    • Syndrome
      • 4H

Clinical ClassificationClinical

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

CCSR DEN001
Any dental condition including traumatic injury
Default principal diagnosis: inpatient No · outpatient No
CCSR DIG002
Disorders of teeth and gingiva
Default principal diagnosis: inpatient No · outpatient No
CCSR DEN002
Nontraumatic dental conditions
Default principal diagnosis: inpatient No · outpatient No
CCSR NVS006
Other nervous system disorders (often hereditary or degenerative)
Default principal diagnosis: inpatient Yes · outpatient Yes
CCSR END013
Pituitary disorders
Default principal diagnosis: inpatient No · outpatient No

Code History & ChangesHistory

Replacement G11.5 replaces the following previously assigned code(s):

  • E23.0 - Hypopituitarism
  • G11.8 - Other hereditary ataxias
  • K00.0 - Anodontia
FY 2024AddedAdded to the ICD-10-CM code setEffective October 1, 2023.
FY 2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About G11.5Overview

Is G11.5 (Hereditary ataxia) a billable code?

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

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.