G40.401
BillableOther generalized epilepsy and epileptic syndromes, not intractable, with status epilepticus
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is G40.401 an HCC code?
Yes. G40.401 maps to Seizure Disorders and Convulsions under the CMS-HCC V28 risk adjustment model (and Seizure Disorders and Convulsions under V24).
HCC Category Mapping
RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.
MEAT Criteria for G40.401
For G40.401 to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically — it has to be re-documented and supported each calendar year.
- MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
- EEvaluate: test results, medication response, or physical findings reviewed by the provider
- AAssess: explicit mention in the assessment or plan with acknowledgment of status
- TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis
Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed G40.401 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
G40.401 is the ICD-10-CM diagnosis code for other generalized epilepsy and epileptic syndromes, not intractable, with status epilepticus. A generalized epilepsy of a type other than idiopathic that is controllable with medication, but the patient is currently experiencing status epilepticus. G40.401 sits in the ICD-10-CM chapter for diseases of the nervous system (g00-g99), within the section covering episodic and paroxysmal disorders (g40-g47).
Under the CMS-HCC V28 risk adjustment model, G40.401 maps to Seizure Disorders and Convulsions (HCC 201) with a community, non-dual, aged base RAF weight of 0.262. Under the older V24 model, G40.401 mapped to the same category but with a base RAF weight of 0.244 — V28 recalibrated weights across the entire model. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.
The '4' in the fourth character indicates 'other' generalized epilepsy, which may have a secondary cause that should be documented. Because G40.401 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for G40.401 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •The '4' in the fourth character indicates 'other' generalized epilepsy, which may have a secondary cause that should be documented
- •Identify and document the underlying cause (e.g., brain injury, infection, tumor) if known
Clinical Significance
Other generalized epilepsy with status epilepticus represents a neurological emergency where seizures involve both brain hemispheres and persist beyond 5 minutes or recur without recovery. This diagnosis drives significant resource utilization for emergency management including IV benzodiazepines, continuous EEG monitoring, and potential ICU admission. Accurate capture is critical for risk adjustment as it reflects a patient with higher-than-average healthcare needs.
Documentation Requirements
- ✓Specific type of generalized epilepsy documented (e.g., secondary to brain injury, infection, or tumor)
- ✓Statement confirming seizures are NOT intractable/drug-resistant (responsive to medication)
- ✓Documentation of active status epilepticus during the encounter (seizure duration >5 minutes or recurrent seizures without recovery)
- ✓Current antiepileptic drug regimen with dosages
- ✓Emergency interventions provided for status epilepticus
- ✓Underlying etiology if known (structural, metabolic, genetic)