G40.4

Other generalized epilepsy and epileptic syndromes

FY2027Chapter 6: Diseases of the nervous system/G40–G47 Episodic and paroxysmal disorders

Non-billable headerNot valid on its own. Use one of the more specific codes under it.

G40.4 is a non-billable ICD-10-CM code header for other generalized epilepsy and epileptic syndromes. Report a more specific code from it instead. It is part of the FY2027 code set, effective October 1, 2026. The more specific codes under it are G40.40 Other generalized epilepsy and epileptic syndromes, not intractable; G40.41 Other generalized epilepsy and epileptic syndromes, intractable and G40.42 Cyclin-Dependent Kinase-Like 5 Deficiency Disorder. Its coding notes include 5 Excludes1 entries and 12 Excludes2 entries.

Excludes1

Not coded here. The listed conditions generally should not be reported together.

Inherited from G40 Epilepsy and recurrent seizures
  • 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. Both codes may be reported if the patient has both conditions.

Inherited from G40 Epilepsy and recurrent seizures
Also from chapter/block level (8 notes)
Inherited from Chapter 6 Diseases of the nervous system
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

Inclusion terms

Conditions classified to this code.

This code
  • Epilepsy with grand mal seizures on awakening
  • Epilepsy with myoclonic absences
  • Epilepsy with myoclonic-astatic seizures
  • Grand mal seizure NOS
  • Nonspecific atonic epileptic seizures
  • Nonspecific clonic epileptic seizures
  • Nonspecific myoclonic epileptic seizures
  • Nonspecific tonic epileptic seizures
  • Nonspecific tonic-clonic epileptic seizures
  • Symptomatic early myoclonic encephalopathy

Notes

Inherited 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

Alphabetic Index terms

Terms the official Alphabetic Index lists for this code. 1 entry

More specific codes under G40.4 3