ICD-10 Code G40.811 – Lennox-Gastaut syndrome, not intractable, with status epilepticus (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code G40.811 – Lennox-Gastaut syndrome, not intractable, with status epilepticus
What it is
G40.811 identifies Lennox-Gastaut syndrome when seizures are not described as intractable and the patient is documented as having status epilepticus. Use it for this specific epilepsy syndrome, not for generalized seizures alone.
Clinical signs
Typical documentation may include multiple seizure types, developmental impairment, and an electroclinical syndrome consistent with Lennox-Gastaut. Status epilepticus means prolonged or repeated seizures without recovery between events; clinical features vary, so refer to documentation.
When to use this code
Use this code when the record clearly states Lennox-Gastaut syndrome and also notes status epilepticus, while the epilepsy is not documented as intractable. It is appropriate for discharge summaries, neurology notes, or problem lists that confirm both elements. If the chart does not specify intractability, code the documented status only if supported.
Do not use for
Do not use G40.811 for Lennox-Gastaut syndrome without status epilepticus, or when the epilepsy is documented as intractable. Check documentation if the note only says seizure disorder, convulsions, or epilepsy NOS.
Coding tip
Verify both the syndrome and the status epilepticus wording before assigning G40.811.