ICD-10-CM 2027 diagnosis code

G40.50Epileptic seizures related to external causes, not intractable

Not billable — use a more specific code

G40.50 is a header code, so it can't be reported by itself. Choose one of the 2 more specific codes beneath it.Short description: Epileptic seizures related to external causes, not ntrct

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About G40.50

G40.50 is the ICD-10-CM diagnosis code for epileptic seizures related to external causes, not intractable. It belongs to category G40 (epilepsy and recurrent seizures), block G40-G47 (episodic and paroxysmal disorders) and chapter 6 (diseases of the nervous system). It is a header code, so it can't be reported by itself; one of its 2 subcodes must be used instead.

To report this condition, pick the subcode that matches the documentation: G40.501 (with status epilepticus) and G40.509 (without status epilepticus).

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Specific codes under G40.50

Notes that apply from higher levels

Instructions written at a parent level also apply to G40.50.

› From G40.5 Epileptic seizures related to external causes

Use additional code

code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5)

Code also

, if applicable, associated epilepsy and recurrent seizures (G40.-)

› From G40 Epilepsy and recurrent seizures

Note

the following terms are to be considered equivalent to intractable: pharmacoresistant (pharmacologically resistant), treatment resistant, refractory (medically) and poorly controlled

Excludes1

conversion disorder with seizures (F44.5)
convulsions NOS (R56.9)
post traumatic seizures (R56.1)
seizure (convulsive) NOS (R56.9)
seizure of newborn (P90)

Excludes2

hippocampal sclerosis (G93.81)
mesial temporal sclerosis (G93.81)
temporal sclerosis (G93.81)
Todd's paralysis (G83.84)

Broader instructions also apply from Chapter 6: Diseases of the nervous system.

Code history

2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027

FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
No changes since FY2016.

Common questions about G40.50

Is G40.50 billable?: No. G40.50 is a header code. Report one of its more specific subcodes instead.