G40.834 ICD-10-CM Code: Dravet syndrome, intractable, without status epilepticus
Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.
Inpatient Payment Groups (MS-DRG)
MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v43.0, Appendix B.
- MS-DRG 023 — CRANIOTOMY WITH MAJOR DEVICE IMPLANT OR ACUTE COMPLEX CNS PRINCIPAL DIAGNOSIS WITH MCC OR ANTINEOPLASTIC IMPLANT OR EPILEPSY WITH NEUROSTIMULATOR (MDC 01)
- MS-DRG 100 — SEIZURES WITH MCC (MDC 01)
- MS-DRG 101 — SEIZURES WITHOUT MCC (MDC 01)
A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.
Risk Adjustment (CMS-HCC)
Payment categories this diagnosis maps to under CMS-HCC V28, payment year 2026.
- HCC 201 — Seizure Disorders and Convulsions
Other models: CMS-HCC V22 HCC 79 · RxHCC V08 HCC 163
Risk scores depend on the enrollee's full accepted diagnosis set and segment; a category mapping alone does not determine payment.
Official Registry Overview & Definition
Official Tabular Instructional Notes
Sequencing, inclusion, and exclusion notes published for G40.834 in the official ICD-10-CM tabular list.
Inclusion Terms
Alternative terms the tabular list files under this code.
- Dravet syndrome NOS
Excludes1 — Not Coded Here
Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
- conversion disorder with seizures (F44.5) Compare G40.834 vs F44.5 →
- convulsions NOS (R56.9) Compare G40.834 vs R56.9 →
- post traumatic seizures (R56.1) Compare G40.834 vs R56.1 →
- seizure (convulsive) NOS (R56.9) Compare G40.834 vs R56.9 →
- seizure of newborn (P90) Compare G40.834 vs P90 →
Excludes2 — Not Included Here
Conditions not covered by this code, but which may be reported alongside it when both are present.
- hippocampal sclerosis (G93.81) Compare G40.834 vs G93.81 →
- mesial temporal sclerosis (G93.81) Compare G40.834 vs G93.81 →
- temporal sclerosis (G93.81) Compare G40.834 vs G93.81 →
- Todd's paralysis (G83.84) Compare G40.834 vs G83.84 →
Frequently Compared Codes
The official Excludes notes on G40.834 name these codes. Each comparison page covers when the two can — or must not — be reported together.
Change history
- FY2021 — 2020-10-01Added to the code setDravet syndrome, intractable, without status epilepticusFY2021 changes
Verify Before Coding
- CC as a secondary diagnosis (FY2026). Can raise the stay's MS-DRG severity tier.
From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim.
Contextual Map
Every relationship of G40.834 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.
Hierarchy
- G00-G99 — Chapter 6: Diseases of the Nervous System (G00-G99) (G00-G99) [Hierarchy]
- G40-G47 — Episodic and paroxysmal disorders [Hierarchy]
Referenced by Excludes1 notes
- G25.3 — Myoclonus [Excludes1](via G40.-): “myoclonic epilepsy (G40.-)” · check together
- R56 — Convulsions, not elsewhere classified [Excludes1](via G40.-): “epileptic convulsions and seizures (G40.-)” · check together
- R56.1 — Post traumatic seizures [Excludes1](via G40.-): “post traumatic epilepsy (G40.-)” · check together
Referenced by Excludes2 notes
- F44.0 — Dissociative amnesia [Excludes2](via G40.-): “postictal amnesia in epilepsy (G40.-)” · check together
- F44.1 — Dissociative fugue [Excludes2](via G40.-): “postictal fugue in epilepsy (G40.-)” · check together
Referenced by Code First instructions
- F02 — Dementia in other diseases classified elsewhere [Code First](via G40.-): “epilepsy and recurrent seizures (G40.-)” · check together
Referenced by Use Additional Code instructions
- Q87.87 — Hao-Fountain Syndrome [Use Additional Code](via G40.-): “epilepsy, by specific type (G40.-)” · check together
- Q93.52 — Phelan-McDermid syndrome [Use Additional Code](via G40.-): “epilepsy and recurrent seizures (G40.-)” · check together
Referenced by Code Also instructions (9)
- E20.810 — Autosomal dominant hypocalcemia [Code Also](via G40.-): “seizure disorder (G40.-, R56.9)” · check together
- F78.A1 — SYNGAP1-related intellectual disability [Code Also](via G40.-): “epilepsy and recurrent seizures (G40.-)” · check together
- G04.8 — Other encephalitis, myelitis and encephalomyelitis [Code Also](via G40.-): “any associated seizure (G40.-, R56.9)” · check together
- G43.1 — Migraine with aura [Code Also](via G40.-): “any associated seizure (G40.-, R56.9)” · check together
- G93.45 — Developmental and epileptic encephalopathy [Code Also](via G40.-): “epilepsy, by specific type (G40.-)” · check together
- I67.850 — Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy [Code Also](via G40.-): “epilepsy (G40.-)” · check together
- Q87.85 — MED13L syndrome [Code Also](via G40.-): “epilepsy and recurrent seizures (G40.-)” · check together
- QA0 — Neurodevelopmental disorders related to specific genetic pathogenic variants [Code Also](via G40.-): “epilepsy, by specific type (G40.-)” · check together
- and 1 more
Clinical classification (CCSR)
- NVS009 — Epilepsy; convulsions [CCSR]
Risk adjustment (CMS-HCC)
- HCC 201 — Seizure Disorders and Convulsions [CMS-HCC]
Potential MS-DRG
- CC — Complication or Comorbidity [MS-DRG severity]: “As a secondary diagnosis this code can raise the stay's MS-DRG severity tier (CC).”
- DRG 023 — CRANIOTOMY WITH MAJOR DEVICE IMPLANT OR ACUTE COMPLEX CNS PRINCIPAL DIAGNOSIS WITH MCC OR ANTINEOPLASTIC IMPLANT OR EPILEPSY WITH NEUROSTIMULATOR [MS-DRG]: “CRANIOTOMY WITH MAJOR DEVICE IMPLANT OR ACUTE COMPLEX CNS PRINCIPAL DIAGNOSIS WITH MCC OR ANTINEOPLASTIC IMPLANT OR EPILEPSY WITH NEUROSTIMULATOR (MDC 01)”
- DRG 100 — SEIZURES WITH MCC [MS-DRG]: “SEIZURES WITH MCC (MDC 01)”
- DRG 101 — SEIZURES WITHOUT MCC [MS-DRG]: “SEIZURES WITHOUT MCC (MDC 01)”
MDC crossing · procedures (8892)
- MDC 01 — Diseases and Disorders of the Nervous System [MDC crossing]: “Diseases and Disorders of the Nervous System — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs.”
- 0016070 — Bypass Cerebral Ventricle to Nasopharynx with Autologous Tissue Substitute, Open Approach [Same-MDC procedure]: “Bypass Cerebral Ventricle to Nasopharynx with Autologous Tissue Substitute, Open Approach — grouped in MDC 01, the procedure side of this code's crossing.” · check together
- 0016071 — Bypass Cerebral Ventricle to Mastoid Sinus with Autologous Tissue Substitute, Open Approach [Same-MDC procedure]: “Bypass Cerebral Ventricle to Mastoid Sinus with Autologous Tissue Substitute, Open Approach — grouped in MDC 01, the procedure side of this code's crossing.” · check together
- 0016072 — Bypass Cerebral Ventricle to Atrium with Autologous Tissue Substitute, Open Approach [Same-MDC procedure]: “Bypass Cerebral Ventricle to Atrium with Autologous Tissue Substitute, Open Approach — grouped in MDC 01, the procedure side of this code's crossing.” · check together
- 0016073 — Bypass Cerebral Ventricle to Blood Vessel with Autologous Tissue Substitute, Open Approach [Same-MDC procedure]: “Bypass Cerebral Ventricle to Blood Vessel with Autologous Tissue Substitute, Open Approach — grouped in MDC 01, the procedure side of this code's crossing.” · check together
- 0016074 — Bypass Cerebral Ventricle to Pleural Cavity with Autologous Tissue Substitute, Open Approach [Same-MDC procedure]: “Bypass Cerebral Ventricle to Pleural Cavity with Autologous Tissue Substitute, Open Approach — grouped in MDC 01, the procedure side of this code's crossing.” · check together
- and 8887 more
Index entries
- Syndrome, Dravet (intractable)[Index term]
- Syndrome, Dravet (intractable), without status epilepticus[Index term]
Nearest codes (40)
- G40 — Epilepsy and recurrent seizures [Sibling]
- G40.501 — Epileptic seizures related to external causes, not intractable, with status epilepticus [Sibling]
- G40.509 — Epileptic seizures related to external causes, not intractable, without status epilepticus [Sibling]
- G40.8 — Other epilepsy and recurrent seizures [Sibling]
- G40.80 — Other epilepsy [Sibling]
- G40.801 — Other epilepsy, not intractable, with status epilepticus [Sibling]
- G40.802 — Other epilepsy, not intractable, without status epilepticus [Sibling]
- G40.803 — Other epilepsy, intractable, with status epilepticus [Sibling]
- and 32 more
Change history
- FY2021 — Added to the code set [Change history]
Referenced by Other Codes
Clinical classification (AHRQ CCSR):NVS009 — Epilepsy; convulsions (default).
Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.
Potential MS-DRG Relationships (FY2026)
CC — Complication or Comorbidity. Reported as a secondary diagnosis, this code raises the stay's MS-DRG severity tier — except when the principal diagnosis is one of 54 clinically related codes on its CMS exclusion list.
Named in the grouper logic of 3 MS-DRGs: DRG 023 (MDC 01), DRG 100 (MDC 01), DRG 101 (MDC 01).
From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.
Official ICD-10-CM tabular notes on other codes that name G40.834 or its code family.
3 Excludes1 notes across 2 chapters: G25.3 (via G40.-), R56 (via G40.-), R56.1 (via G40.-).
2 Excludes2 notes: F44.0 (via G40.-), F44.1 (via G40.-).
1 Code First instructions: F02 (via G40.-).
2 Use Additional Code instructions: Q87.87 (via G40.-), Q93.52 (via G40.-).
9 Code Also instructions across 7 chapters: E20.810 (via G40.-), F78.A1 (via G40.-), G04.8 (via G40.-), G43.1 (via G40.-), G93.45 (via G40.-), I67.850 (via G40.-), Q87.85 (via G40.-), QA0 (via G40.-), Z15.1 (via G40.-).
Nearest Codes in This Family
Official ICD-10-CM classifications closest to G40.834 in its code family, with their registry titles.
- G40.822 — Epileptic spasms, not intractable, without status epilepticus
- G40.823 — Epileptic spasms, intractable, with status epilepticus
- G40.824 — Epileptic spasms, intractable, without status epilepticus
- G40.83 — Dravet syndrome
- G40.833 — Dravet syndrome, intractable, with status epilepticus
- G40.84 — KCNQ2-related epilepsy
- G40.841 — KCNQ2-related epilepsy, not intractable, with status epilepticus
- G40.842 — KCNQ2-related epilepsy, not intractable, without status epilepticus
- G40.843 — KCNQ2-related epilepsy, intractable, with status epilepticus
- G40.844 — KCNQ2-related epilepsy, intractable, without status epilepticus
Indexed Clinical Terms (2)
Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code.
- Syndrome, Dravet (intractable)
- Syndrome, Dravet (intractable), without status epilepticus