ICD-10-CM 2027 diagnosis code
G40.A01Absence epileptic syndrome, not intractable, with status epilepticus
G40.A01 is a valid, billable ICD-10-CM code for absence epileptic syndrome, not intractable, with status epilepticus. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.Short description: Absence epileptic syndrome, not intractable, w stat epi
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.A01
G40.A01 is the ICD-10-CM diagnosis code for absence epileptic syndrome, not intractable, with status epilepticus. 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 billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.
Within G40.A0 (absence epileptic syndrome, not intractable), G40.A01 is specifically for absence epileptic syndrome, not intractable, with status epilepticus. Related codes cover without status epilepticus (G40.A09).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 023 (Craniotomy with Major Device Implant or Acute Complex CNS Principal Diagnosis with MCC or Antineoplastic Implant or Epilepsy with Neurostimulator, relative weight 5.7444), DRG 100 (Seizures with MCC, relative weight 1.9233) and DRG 101 (Seizures without MCC, relative weight 0.8952), in MDC 01 (Diseases and Disorders of the Nervous System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
Before ICD-10, this condition was coded in ICD-9-CM as 345.00 (generalized nonconvulsive epilepsy, without mention of intractable epilepsy) and 345.2 (petit mal status).
Notes that apply from higher levels
Instructions written at a parent level also apply to G40.A01.
› From G40 Epilepsy and recurrent seizures
- the following terms are to be considered equivalent to intractable: pharmacoresistant (pharmacologically resistant), treatment resistant, refractory (medically) and poorly controlled
Broader instructions also apply from Chapter 6: Diseases of the nervous system.
Alphabetic index entries
5 entriesTerms in the official ICD-10-CM index that lead to G40.A01.
- Epilepsy, epileptic, epilepsia (attack) (cerebral) (convulsion) (fit) (seizure) › childhood › absence › not intractable › with status epilepticus
- Epilepsy, epileptic, epilepsia (attack) (cerebral) (convulsion) (fit) (seizure) › juvenile absence › not intractable › with status epilepticus
- Pyknolepsy › not intractable › with status epilepticus
- Seizure (s) › petit mal › not intractable › with status epilepticus
- Syndrome › epileptic › absence › not intractable › with status epilepticus
MS-DRG v44.0 grouping
All DRGs →Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.
MDC 01 · Diseases and Disorders of the Nervous System
MDC 01 · Diseases and Disorders of the Nervous System
ICD-9-CM equivalent
Converter →- 345.00Generalized nonconvulsive epilepsy, without mention of intractable epilepsyapproximate
- 345.2Petit mal statusapproximate
From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.
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.A01
Is G40.A01 billable?
- Yes. G40.A01 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can G40.A01 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict G40.A01 as a principal diagnosis.
Is G40.A01 a CC or MCC?
- No. G40.A01 is neither a CC nor an MCC under MS-DRG v44.0.
What DRG does G40.A01 group to?
- G40.A01 is used in the MS-DRG v44.0 logic for MS-DRG 023 (Craniotomy with Major Device Implant or Acute Complex CNS Principal Diagnosis with MCC or Antineoplastic Implant or Epilepsy with Neurostimulator), MS-DRG 100 (Seizures with MCC) and MS-DRG 101 (Seizures without MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.
What is the ICD-9 code for G40.A01?
- The CMS General Equivalence Mappings map G40.A01 to ICD-9-CM 345.00 and 345.2.