MCMCB Pro
G40.5

G40.5Epileptic seizures related to external causes

Non-billable headerICD-10-CM

G40.5 is a non-billable header ICD-10-CM code for epileptic seizures related to external causes. It cannot be billed on its own: choose one of the more specific child codes below.

Use additional code

Add a secondary code to capture the detail described below.

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

Code also

Both codes may be needed to describe the encounter fully. Sequencing depends on the reason for the visit.

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

Inclusion terms

Alternative wordings a physician may use in the chart for this same 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

Risk adjustment

G40.5 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Code to one of these instead G40.5

1 child code. Green means billable.

Related codes at this level

Codes that share G40. If G40.5 is not quite right, the correct code is usually one of these.

Questions about G40.5

Is G40.5 a billable ICD-10-CM code?
No. G40.5 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does G40.5 sit in the tabular list?
Diseases of the nervous system (G00-G99), in the block Episodic and paroxysmal disorders (G40-G47).
ICD-10-CMFY2026-Apr· effective April 1, 2026

Loaded directly from the CMS/NCHS ICD-10-CM public-domain release — see data sources and our editorial policy. If this page disagrees with the CMS tabular list, this page is wrong. Reference information for professional coders; not medical or billing advice.