G40.A1 – Absence epileptic syndrome, intractable

ICD-10-CM 2027 diagnosis code · Episodic and paroxysmal disorders

Non-billable header

ICD-10-CM code G40.A1

Code: G40.A1 (claims format: G40A1)
Description: Absence epileptic syndrome, intractable
Billable: No – use a more specific code below
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 6. Diseases of the nervous system (G00-G99)
Block: G40-G47 Episodic and paroxysmal disorders
Parent codes: G40 › G40.A

Billable codes under G40.A1

G40.A1 is a header code and cannot be used on claims. Choose the most specific code:

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

G40 – Epilepsy and recurrent seizures

Excludes1 (not coded here):

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 (not included here):

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

Notes:

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

G40.A – Absence epileptic syndrome

Applicable to:

Childhood absence epilepsy [pyknolepsy]
Juvenile absence epilepsy
Absence epileptic syndrome, NOS

Index terms for G40.A1

Entries in the ICD-10-CM alphabetic index that lead to this code:

Seizure, petit mal, intractable

Related codes in G40.A

G40.A0 – Absence epileptic syndrome, not intractableHeader

Frequently asked questions

What is ICD-10 code G40.A1?

G40.A1 is the ICD-10-CM code for absence epileptic syndrome, intractable, in the block G40-G47 (Episodic and paroxysmal disorders).

Is G40.A1 a billable code?

No. G40.A1 is a header code with more specific child codes; report one of the billable codes listed above.

What category does G40.A1 belong to?

It belongs to category G40 – Epilepsy and recurrent seizures.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.