ICD-10 Code G40.2 – Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with complex partial seizures (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code G40.2 – Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with complex partial seizures
What it is
This code identifies a focal epilepsy syndrome caused by an underlying brain lesion or known structural problem, with seizures that impair awareness. It is used when documentation supports symptomatic localization-related epilepsy with complex partial seizures.
Clinical signs
Typical features include brief focal seizures with altered awareness, staring, automatisms, and possible postictal confusion. Clinical features vary; refer to documentation for the seizure type and any confirmed symptomatic cause.
When to use this code
Use G40.2 when the record states localization-related symptomatic epilepsy and describes complex partial seizures, or when the provider clearly documents a focal epilepsy syndrome with impaired awareness. You should also confirm the cause is symptomatic, not idiopathic or unspecified. If the note is unclear, check documentation.
Do not use for
Do not use this code for generalized epilepsy, simple partial seizures without impaired awareness, or seizures not documented as epileptic. Do not assign it when the seizure type or symptomatic cause is not supported; check documentation.
Coding tip
Match both the epilepsy type and seizure description in the note before coding.