ICD-10 Code G40.40 – Other generalized epilepsy and epileptic syndromes, not intractable (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code G40.40 – Other generalized epilepsy and epileptic syndromes, not intractable
What it is
This code identifies generalized epilepsy or an epileptic syndrome that affects both sides of the brain and is not described by a more specific category. “Not intractable” means the seizures are not documented as difficult to control.
Clinical signs
Clinical features vary; refer to documentation. You may see generalized seizure types, such as absence, myoclonic, or tonic-clonic events, with EEG or neurologic findings supporting a generalized epilepsy syndrome.
When to use this code
Use G40.40 when the provider documents a generalized epilepsy syndrome and does not state it is intractable or refractory. It also fits when the diagnosis is clear but the record does not support a more specific generalized epilepsy code.
Do not assume focal epilepsy, status epilepticus, or a seizure disorder without an epilepsy diagnosis. Check documentation for the exact syndrome name and whether seizure control is described.
Do not use for
Do not use this code for intractable generalized epilepsy, focal epilepsy, or isolated seizures without a documented epilepsy syndrome. Check documentation if the record only says “seizure.”
Coding tip
Code the most specific epilepsy type documented, and verify whether “intractable” or “not intractable” is explicitly stated.