ICD-10 Code G40.9 – Epilepsy, unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code G40.9 – Epilepsy, unspecified
What it is
G40.9 identifies epilepsy when the record confirms recurrent seizures but does not specify the epilepsy type or syndrome. Use it for a documented epilepsy diagnosis without further detail.
Clinical signs
Clinical features vary; refer to documentation. Common records mention recurrent unprovoked seizures, loss of awareness, convulsive episodes, or postictal confusion, but the chart must support epilepsy rather than a single isolated seizure.
When to use this code
Use G40.9 when the provider documents epilepsy and does not name a more specific category, such as focal, generalized, or syndromic epilepsy. It also fits when the type remains unspecified after evaluation. If the note only says “seizure,” check documentation before coding.
Do not use for
Do not use this code for a single seizure, seizure disorder without confirmed epilepsy, or episodes clearly due to another cause. If the record identifies a specific epilepsy type, code that more precise option instead.
Coding tip
Code the highest level of specificity available, and query the provider if the record says epilepsy but leaves the type unclear.