ICD10BillableValid for clinical use

ICD-10 Code G40.813: Lennox-Gastaut syndrome, intractable, with status epilepticus

G40.813 is a billable ICD-10 diagnosis code used to classify Lennox-Gastaut syndrome, intractable, with status epilepticus in medical records and claims. You may see this code in hospital records, discharge summaries, insurance claims, encounter documentation, referrals, or other healthcare billing and coding records. ICD-10 codes are diagnosis classification codes used in healthcare records, reporting, coding workflows, and billing support. This code sits within the broader ICD-10 area for Diseases of the nervous system (G00-G99).

Reviewed by HealthAssure Clinical TeamUpdated 26 May 2026

What is this code?

ICD-10 codes are diagnosis classification codes used in healthcare records, reporting, coding workflows, and billing support. This code sits within the broader ICD-10 area for Diseases of the nervous system (G00-G99).

When is it used?

  • May be used when a clinician documents lennox-gastaut syndrome, intractable, with status epilepticus in a patient's medical record.
  • May appear in hospital records, claims, referrals, and clinical documentation.
  • This code can be used as a clinically usable diagnosis entry in standardized coding workflows.

What it does not mean

  • A code alone does not explain severity, treatment plan, or outcome.
  • A medical code should not be treated as a substitute for a doctor's diagnosis or advice.

Code hierarchy

chapter
6Diseases of the nervous system (G00-G99)
block
G40-G47Episodic and paroxysmal disorders
category
G40Epilepsy and recurrent seizures
category
G40.8Other epilepsy and recurrent seizures
category
G40.81Lennox-Gastaut syndrome
currentG40.81

Where you may see this code

You may see this code in hospital records, discharge summaries, insurance claims, encounter documentation, referrals, or other healthcare billing and coding records.

Related specialists

NeurologistGeneral Physician

Coverage-related procedures and services

CPT 81225high
CYP2C19 (CYTOCHROME P450, FAMILY 2, SUBFAMILY C, POLYPEPTIDE 19) (EG, DRUG METABOLISM), GENE ANALYSIS, COMMON VARIANTS (EG, *2, *3, *4, *8, *17)
Source: CMS coverage guidance
CPT 81418high
DRUG METABOLISM (EG, PHARMACOGENOMICS) GENOMIC SEQUENCE ANALYSIS PANEL, MUST INCLUDE TESTING OF AT LEAST 6 GENES, INCLUDING CYP2C19, CYP2D6, AND CYP2D6 DUPLICATION/DELETION ANALYSIS
Source: CMS coverage guidance
CPT 0349Uhigh
DRUG METABOLISM OR PROCESSING (MULTIPLE CONDITIONS), WHOLE BLOOD OR BUCCAL SPECIMEN, DNA ANALYSIS, 27 GENE REPORT, WITH VARIANT ANALYSIS, INCLUDING REPORTED PHENOTYPES AND IMPACTED GENE-DRUG INTERACTIONS
Source: CMS coverage guidance
CPT 95700high
ELECTROENCEPHALOGRAM (EEG) CONTINUOUS RECORDING, WITH VIDEO WHEN PERFORMED, SETUP, PATIENT EDUCATION, AND TAKEDOWN WHEN PERFORMED, ADMINISTERED IN PERSON BY EEG TECHNOLOGIST, MINIMUM OF 8 CHANNELS
Source: CMS coverage guidance
CPT 95705high
ELECTROENCEPHALOGRAM (EEG), WITHOUT VIDEO, REVIEW OF DATA, TECHNICAL DESCRIPTION BY EEG TECHNOLOGIST, 2-12 HOURS; UNMONITORED
Source: CMS coverage guidance
CPT 95708high
ELECTROENCEPHALOGRAM (EEG), WITHOUT VIDEO, REVIEW OF DATA, TECHNICAL DESCRIPTION BY EEG TECHNOLOGIST, EACH INCREMENT OF 12-26 HOURS; UNMONITORED
Source: CMS coverage guidance

Coding guidelines

Common synonyms

Lennox-Gastaut syndrome, intractable, with status epilepticus

Frequently asked questions

Code details

CodeG40.813
SystemICD10
Display nameLennox-Gastaut syndrome, intractable, with status epilepticus
ChapterDiseases of the nervous system (G00-G99)
BlockEpisodic and paroxysmal disorders

Flags

BillableYes
Valid clinical useYes

Source

SourceICD-10
Version2026-annual
Releaseannual
Year2026

Index terms

Matched terms
Lennox-Gastaut syndromeSyndrome

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.

ICD-10 Code G40.813 for Lennox-Gastaut syndrome, intractable, with status epilepticus | HealthAssure