ICD10BillableValid for clinical use

ICD-10 Code G40.844: KCNQ2-related epilepsy, intractable, without status epilepticus

G40.844 is a billable ICD-10 diagnosis code used to classify KCNQ2-related epilepsy, intractable, without 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 kcnq2-related epilepsy, intractable, without 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
G40.84KCNQ2-related epilepsy
currentG40.84

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 96105high
ASSESSMENT OF APHASIA (INCLUDES ASSESSMENT OF EXPRESSIVE AND RECEPTIVE SPEECH AND LANGUAGE FUNCTION, LANGUAGE COMPREHENSION, SPEECH PRODUCTION ABILITY, READING, SPELLING, WRITING, EG, BY BOSTON DIAGNOSTIC APHASIA EXAMINATION) WITH INTERPRETATION AND REPORT, PER HOUR
Source: CMS coverage guidance
CPT 70460high
COMPUTED TOMOGRAPHY, HEAD OR BRAIN; WITH CONTRAST MATERIAL(S)
Source: CMS coverage guidance
CPT 70450high
COMPUTED TOMOGRAPHY, HEAD OR BRAIN; WITHOUT CONTRAST MATERIAL
Source: CMS coverage guidance
CPT 70470high
COMPUTED TOMOGRAPHY, HEAD OR BRAIN; WITHOUT CONTRAST MATERIAL, FOLLOWED BY CONTRAST MATERIAL(S) AND FURTHER SECTIONS
Source: CMS coverage guidance
CPT 96113high
DEVELOPMENTAL TEST ADMINISTRATION (INCLUDING ASSESSMENT OF FINE AND/OR GROSS MOTOR, LANGUAGE, COGNITIVE LEVEL, SOCIAL, MEMORY AND/OR EXECUTIVE FUNCTIONS BY STANDARDIZED DEVELOPMENTAL INSTRUMENTS WHEN PERFORMED), BY PHYSICIAN OR OTHER QUALIFIED HEALTH CARE PROFESSIONAL, WITH INTERPRETATION AND REPORT; EACH ADDITIONAL 30 MINUTES (LIST SEPARATELY IN ADDITION TO CODE FOR PRIMARY PROCEDURE)
Source: CMS coverage guidance
CPT 96112high
DEVELOPMENTAL TEST ADMINISTRATION (INCLUDING ASSESSMENT OF FINE AND/OR GROSS MOTOR, LANGUAGE, COGNITIVE LEVEL, SOCIAL, MEMORY AND/OR EXECUTIVE FUNCTIONS BY STANDARDIZED DEVELOPMENTAL INSTRUMENTS WHEN PERFORMED), BY PHYSICIAN OR OTHER QUALIFIED HEALTH CARE PROFESSIONAL, WITH INTERPRETATION AND REPORT; FIRST HOUR
Source: CMS coverage guidance

Coding guidelines

Common synonyms

KCNQ2-related epilepsy, intractable, without status epilepticus

Frequently asked questions

Code details

CodeG40.844
SystemICD10
Display nameKCNQ2-related epilepsy, intractable, without 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
Epilepsy, epileptic, epilepsia(attack) (cerebral) (convulsion) (fit) (seizure)Epilepsy, epileptic, epilepsia(attack) (cerebral) (convulsion) (fit) (seizure)

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 G40.844 for KCNQ2-related epilepsy, intractable, without status epilepticus | HealthAssure