Alphabetic Index FY2027

G40.5

Epileptic seizures related to external causes

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.

G40.5 is a non-billable ICD-10-CM code header for epileptic seizures related to external causes. Report a more specific code from it instead. It is part of the FY2027 code set, effective October 1, 2026. The more specific code under it is G40.50 Epileptic seizures related to external causes, not intractable. Its coding notes include a Use additional code instruction, a Code also instruction, 5 Excludes1 entries and 12 Excludes2 entries.

Use additional code

Add the listed code as a secondary code, if known.

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

Code also

Two codes may be needed to describe the condition. This note gives no sequencing order.

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

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
  • Epileptic seizures related to alcohol
  • Epileptic seizures related to drugs
  • Epileptic seizures related to hormonal changes
  • Epileptic seizures related to sleep deprivation
  • Epileptic seizures related to stress

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

More specific codes under G40.5 1