2026 ICD-10-CM Diagnosis Code G92.9Unspecified toxic encephalopathy

ICD-10-CM Codes›G00–G99›G89-G99›G92

ICD-10-CM G92.9
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

G92.9 is a billable ICD-10-CM diagnosis code for unspecified toxic encephalopathy. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Drug induced or toxic related condition and Other nervous system disorders (neither hereditary nor degenerative).

Code Identity

ICD-10-CM Code
G92.9
Billable Status
Yes — Valid for Submission
Code Describes
Unspecified toxic encephalopathy
Short Description
Unspecified toxic encephalopathy
Same as the full description in the CMS dataset.
Parent Code
G92
Toxic encephalopathy

Code Classification

ChapterG00–G99Diseases of the nervous system
SectionG89-G99Other disorders of the nervous system
CategoryG92Toxic encephalopathy
This CodeG92.9Unspecified toxic encephalopathy

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Ammonia encephalopathy
  • Arsenic encephalopathy
  • Carbon monoxide encephalopathy
  • Drug-induced encephalopathy
  • Encephalopathy caused by heavy metal
  • Inflammation of spinal cord caused by toxin
  • Lead and/or lead compound poisoning
  • Organic mercury poisoning
  • Organophosphate encephalopathy
  • Toxic encephalopathy
  • Toxic encephalopathy caused by carbon tetrachloride
  • Toxic encephalopathy caused by hydroxyquinoline
  • Toxic encephalopathy caused by lead
  • Toxic encephalopathy caused by mercury
  • Toxic encephalopathy caused by monomethyl mercury

Tabular List NotesGuidance

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

Code First

  • poisoning due to drug or toxin, if applicable, T36 T65

Use Additional Code

  • code for adverse effect, if applicable, to identify drug T36 T50

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.

    • Encephalopathy(acute)
      • toxic
    • Myelitis(acute) (ascending) (childhood) (chronic) (descending) (diffuse) (disseminated) (idiopathic) (pressure) (progressive) (spinal cord) (subacute)
      • toxic

Clinical ClassificationClinical

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

CCSR INJ030
Drug induced or toxic related condition
Default principal diagnosis: inpatient No · outpatient No
CCSR NVS020
Other nervous system disorders (neither hereditary nor degenerative)
Default principal diagnosis: inpatient Yes · outpatient Yes

Code History & ChangesHistory

Replacement G92.9 replaces the following previously assigned code(s):

  • G92 - Toxic encephalopathy
FY 2022AddedAdded to the ICD-10-CM code setEffective October 1, 2021.
FY 2023–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About G92.9Overview

Is G92.9 (Toxic encephalopathy) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report unspecified toxic encephalopathy 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.