ICD-10-CM 2027
ICD-10 code for epilepsy
From the official ICD-10-CM alphabetic index entry “Epilepsy, epileptic, epilepsia (attack) (cerebral) (convulsion) (fit) (seizure)”. Page updated September 29, 2026.
About coding epilepsy
The ICD-10-CM code for epilepsy is G40.909 (Epilepsy, unspecified, not intractable, without status epilepticus). The official index lists 169 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on G40.909.
Within G40.90, choose G40.909 (without status epilepticus) only when documentation doesn't support a more specific option: with status epilepticus (G40.901).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 023 (Craniotomy with Major Device Implant or Acute Complex CNS Principal Diagnosis with MCC or Antineoplastic Implant or Epilepsy with Neurostimulator, relative weight 5.7444), DRG 100 (Seizures with MCC, relative weight 1.9233) and DRG 101 (Seizures without MCC, relative weight 0.8952), in MDC 01 (Diseases and Disorders of the Nervous System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific epilepsy codes (official index)
- Note: the following terms are to be considered equivalent to intractable: pharmacoresistant (pharmacologically resistant), treatment resistant, refractory (medically) and poorly controlled
- with
- complex partial seizures
- grand mal seizures on awakening
- myoclonic absences
- myoclonic-astatic seizures
- simple partial seizures
- akinetic
- benign childhood with centrotemporal EEG spikes
- benign myoclonic in infancy G40.80 — Other epilepsy
- Bravais-jacksonian
- childhood
- with occipital EEG paroxysms
- absence G40.A09 — Absence epileptic syndrome, not intractable, without status epilepticus
- intractable G40.A19 — Absence epileptic syndrome, intractable, without status epilepticus
- with status epilepticus G40.A11 — Absence epileptic syndrome, intractable, with status epilepticus
- without status epilepticus G40.A19 — Absence epileptic syndrome, intractable, without status epilepticus
- not intractable G40.A09 — Absence epileptic syndrome, not intractable, without status epilepticus
- with status epilepticus G40.A01 — Absence epileptic syndrome, not intractable, with status epilepticus
- without status epilepticus G40.A09 — Absence epileptic syndrome, not intractable, without status epilepticus
- climacteric
- cysticercosis B69.0 — Cysticercosis of central nervous system
- deterioration (mental) F06.8 — Other specified mental disorders due to known physiological condition
- due to syphilis A52.19 — Other symptomatic neurosyphilis
- focal
- generalized
- idiopathic G40.309 — Generalized idiopathic epilepsy and epileptic syndromes, not intractable, without status epilepticus
- intractable G40.319 — Generalized idiopathic epilepsy and epileptic syndromes, intractable, without status epilepticus
- with status epilepticus G40.311 — Generalized idiopathic epilepsy and epileptic syndromes, intractable, with status epilepticus
- without status epilepticus G40.319 — Generalized idiopathic epilepsy and epileptic syndromes, intractable, without status epilepticus
- not intractable G40.309 — Generalized idiopathic epilepsy and epileptic syndromes, not intractable, without status epilepticus
- with status epilepticus G40.301 — Generalized idiopathic epilepsy and epileptic syndromes, not intractable, with status epilepticus
- without status epilepticus G40.309 — Generalized idiopathic epilepsy and epileptic syndromes, not intractable, without status epilepticus
- specified NEC G40.409 — Other generalized epilepsy and epileptic syndromes, not intractable, without status epilepticus
- intractable G40.419 — Other generalized epilepsy and epileptic syndromes, intractable, without status epilepticus
- with status epilepticus G40.411 — Other generalized epilepsy and epileptic syndromes, intractable, with status epilepticus
- without status epilepticus G40.419 — Other generalized epilepsy and epileptic syndromes, intractable, without status epilepticus
- not intractable G40.409 — Other generalized epilepsy and epileptic syndromes, not intractable, without status epilepticus
- with status epilepticus G40.401 — Other generalized epilepsy and epileptic syndromes, not intractable, with status epilepticus
- without status epilepticus G40.409 — Other generalized epilepsy and epileptic syndromes, not intractable, without status epilepticus
- impulsive petit mal
- intractable G40.919 — Epilepsy, unspecified, intractable, without status epilepticus
- with status epilepticus G40.911 — Epilepsy, unspecified, intractable, with status epilepticus
- without status epilepticus G40.919 — Epilepsy, unspecified, intractable, without status epilepticus
- juvenile absence G40.A09 — Absence epileptic syndrome, not intractable, without status epilepticus
- intractable G40.A19 — Absence epileptic syndrome, intractable, without status epilepticus
- with status epilepticus G40.A11 — Absence epileptic syndrome, intractable, with status epilepticus
- without status epilepticus G40.A19 — Absence epileptic syndrome, intractable, without status epilepticus
- not intractable G40.A09 — Absence epileptic syndrome, not intractable, without status epilepticus
- with status epilepticus G40.A01 — Absence epileptic syndrome, not intractable, with status epilepticus
- without status epilepticus G40.A09 — Absence epileptic syndrome, not intractable, without status epilepticus
- juvenile myoclonic G40.B09 — Juvenile myoclonic epilepsy, not intractable, without status epilepticus
- intractable G40.B19 — Juvenile myoclonic epilepsy, intractable, without status epilepticus
- with status epilepticus G40.B11 — Juvenile myoclonic epilepsy, intractable, with status epilepticus
- without status epilepticus G40.B19 — Juvenile myoclonic epilepsy, intractable, without status epilepticus
- not intractable G40.B09 — Juvenile myoclonic epilepsy, not intractable, without status epilepticus
- with status epilepticus G40.B01 — Juvenile myoclonic epilepsy, not intractable, with status epilepticus
- without status epilepticus G40.B09 — Juvenile myoclonic epilepsy, not intractable, without status epilepticus
- KCNQ2-related G40.842 — KCNQ2-related epilepsy, not intractable, without status epilepticus
- intractable G40.844 — KCNQ2-related epilepsy, intractable, without status epilepticus
- with status epilepticus G40.843 — KCNQ2-related epilepsy, intractable, with status epilepticus
- without status epilepticus G40.844 — KCNQ2-related epilepsy, intractable, without status epilepticus
- not intractable G40.842 — KCNQ2-related epilepsy, not intractable, without status epilepticus
- with status epilepticus G40.841 — KCNQ2-related epilepsy, not intractable, with status epilepticus
- without status epilepticus G40.842 — KCNQ2-related epilepsy, not intractable, without status epilepticus
- Lafora progressive myoclonus G40.C09 — Lafora progressive myoclonus epilepsy, not intractable, without status epilepticus
- localization-related (focal) (partial)
- idiopathic G40.009 — Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, not intractable, without status epilepticus
- with seizures of localized onset G40.009 — Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, not intractable, without status epilepticus
- intractable G40.019 — Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, intractable, without status epilepticus
- with status epilepticus G40.011 — Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, intractable, with status epilepticus
- without status epilepticus G40.019 — Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, intractable, without status epilepticus
- not intractable G40.009 — Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, not intractable, without status epilepticus
- with status epilepticus G40.001 — Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, not intractable, with status epilepticus
- without status epilepticus G40.009 — Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, not intractable, without status epilepticus
- symptomatic
- with complex partial seizures G40.209 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with complex partial seizures, not intractable, without status epilepticus
- intractable G40.219 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with complex partial seizures, intractable, without status epilepticus
- with status epilepticus G40.211 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with complex partial seizures, intractable, with status epilepticus
- without status epilepticus G40.219 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with complex partial seizures, intractable, without status epilepticus
- not intractable G40.209 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with complex partial seizures, not intractable, without status epilepticus
- with status epilepticus G40.201 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with complex partial seizures, not intractable, with status epilepticus
- without status epilepticus G40.209 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with complex partial seizures, not intractable, without status epilepticus
- with simple partial seizures G40.109 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures, not intractable, without status epilepticus
- intractable G40.119 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures, intractable, without status epilepticus
- with status epilepticus G40.111 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures, intractable, with status epilepticus
- without status epilepticus G40.119 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures, intractable, without status epilepticus
- not intractable G40.109 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures, not intractable, without status epilepticus
- with status epilepticus G40.101 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures, not intractable, with status epilepticus
- without status epilepticus G40.109 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures, not intractable, without status epilepticus
- myoclonus, myoclonic
- progressive
- Lafora G40.C09 — Lafora progressive myoclonus epilepsy, not intractable, without status epilepticus
- intractable G40.C19 — Lafora progressive myoclonus epilepsy, intractable, without status epilepticus
- with status epilepticus G40.C11 — Lafora progressive myoclonus epilepsy, intractable, with status epilepticus
- without status epilepticus G40.C19 — Lafora progressive myoclonus epilepsy, intractable, without status epilepticus
- not intractable G40.C09 — Lafora progressive myoclonus epilepsy, not intractable, without status epilepticus
- with status epilepticus G40.C01 — Lafora progressive myoclonus epilepsy, not intractable, with status epilepticus
- without status epilepticus G40.C09 — Lafora progressive myoclonus epilepsy, not intractable, without status epilepticus
- type 1
- type 2
- severe, in infancy (SMEI) G40.83 — Dravet syndrome
- not intractable G40.909 — Epilepsy, unspecified, not intractable, without status epilepticus
- with status epilepticus G40.901 — Epilepsy, unspecified, not intractable, with status epilepticus
- without status epilepticus G40.909 — Epilepsy, unspecified, not intractable, without status epilepticus
- on awakening
- parasitic NOS B71.9 — Cestode infection, unspecified
- partial
- partialis continua G40.1 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures
- peripheral
- polymorphic, in infancy (PMEI) G40.83 — Dravet syndrome
- procursiva
- progressive (familial) myoclonic
- Lafora G40.C09 — Lafora progressive myoclonus epilepsy, not intractable, without status epilepticus
- reflex
- related to
- alcohol G40.509 — Epileptic seizures related to external causes, not intractable, without status epilepticus
- not intractable G40.509 — Epileptic seizures related to external causes, not intractable, without status epilepticus
- with status epilepticus G40.501 — Epileptic seizures related to external causes, not intractable, with status epilepticus
- without status epilepticus G40.509 — Epileptic seizures related to external causes, not intractable, without status epilepticus
- drugs G40.509 — Epileptic seizures related to external causes, not intractable, without status epilepticus
- not intractable G40.509 — Epileptic seizures related to external causes, not intractable, without status epilepticus
- with status epilepticus G40.501 — Epileptic seizures related to external causes, not intractable, with status epilepticus
- without status epilepticus G40.509 — Epileptic seizures related to external causes, not intractable, without status epilepticus
- external causes G40.509 — Epileptic seizures related to external causes, not intractable, without status epilepticus
- not intractable G40.509 — Epileptic seizures related to external causes, not intractable, without status epilepticus
- with status epilepticus G40.501 — Epileptic seizures related to external causes, not intractable, with status epilepticus
- without status epilepticus G40.509 — Epileptic seizures related to external causes, not intractable, without status epilepticus
- hormonal changes G40.509 — Epileptic seizures related to external causes, not intractable, without status epilepticus
- not intractable G40.509 — Epileptic seizures related to external causes, not intractable, without status epilepticus
- with status epilepticus G40.501 — Epileptic seizures related to external causes, not intractable, with status epilepticus
- without status epilepticus G40.509 — Epileptic seizures related to external causes, not intractable, without status epilepticus
- sleep deprivation G40.509 — Epileptic seizures related to external causes, not intractable, without status epilepticus
- not intractable G40.509 — Epileptic seizures related to external causes, not intractable, without status epilepticus
- with status epilepticus G40.501 — Epileptic seizures related to external causes, not intractable, with status epilepticus
- without status epilepticus G40.509 — Epileptic seizures related to external causes, not intractable, without status epilepticus
- stress G40.509 — Epileptic seizures related to external causes, not intractable, without status epilepticus
- not intractable G40.509 — Epileptic seizures related to external causes, not intractable, without status epilepticus
- with status epilepticus G40.501 — Epileptic seizures related to external causes, not intractable, with status epilepticus
- without status epilepticus G40.509 — Epileptic seizures related to external causes, not intractable, without status epilepticus
- somatomotor
- somatosensory
- spasms G40.822 — Epileptic spasms, not intractable, without status epilepticus
- intractable G40.824 — Epileptic spasms, intractable, without status epilepticus
- with status epilepticus G40.823 — Epileptic spasms, intractable, with status epilepticus
- without status epilepticus G40.824 — Epileptic spasms, intractable, without status epilepticus
- not intractable G40.822 — Epileptic spasms, not intractable, without status epilepticus
- with status epilepticus G40.821 — Epileptic spasms, not intractable, with status epilepticus
- without status epilepticus G40.822 — Epileptic spasms, not intractable, without status epilepticus
- specified NEC G40.802 — Other epilepsy, not intractable, without status epilepticus
- intractable G40.804 — Other epilepsy, intractable, without status epilepticus
- with status epilepticus G40.803 — Other epilepsy, intractable, with status epilepticus
- without status epilepticus G40.804 — Other epilepsy, intractable, without status epilepticus
- not intractable G40.802 — Other epilepsy, not intractable, without status epilepticus
- with status epilepticus G40.801 — Other epilepsy, not intractable, with status epilepticus
- without status epilepticus G40.802 — Other epilepsy, not intractable, without status epilepticus
- syndromes
- generalized
- idiopathic G40.309 — Generalized idiopathic epilepsy and epileptic syndromes, not intractable, without status epilepticus
- intractable G40.319 — Generalized idiopathic epilepsy and epileptic syndromes, intractable, without status epilepticus
- with status epilepticus G40.311 — Generalized idiopathic epilepsy and epileptic syndromes, intractable, with status epilepticus
- without status epilepticus G40.319 — Generalized idiopathic epilepsy and epileptic syndromes, intractable, without status epilepticus
- not intractable G40.309 — Generalized idiopathic epilepsy and epileptic syndromes, not intractable, without status epilepticus
- with status epilepticus G40.301 — Generalized idiopathic epilepsy and epileptic syndromes, not intractable, with status epilepticus
- without status epilepticus G40.309 — Generalized idiopathic epilepsy and epileptic syndromes, not intractable, without status epilepticus
- specified NEC G40.409 — Other generalized epilepsy and epileptic syndromes, not intractable, without status epilepticus
- intractable G40.419 — Other generalized epilepsy and epileptic syndromes, intractable, without status epilepticus
- with status epilepticus G40.411 — Other generalized epilepsy and epileptic syndromes, intractable, with status epilepticus
- without status epilepticus G40.419 — Other generalized epilepsy and epileptic syndromes, intractable, without status epilepticus
- not intractable G40.409 — Other generalized epilepsy and epileptic syndromes, not intractable, without status epilepticus
- with status epilepticus G40.401 — Other generalized epilepsy and epileptic syndromes, not intractable, with status epilepticus
- without status epilepticus G40.409 — Other generalized epilepsy and epileptic syndromes, not intractable, without status epilepticus
- localization-related (focal) (partial)
- idiopathic G40.009 — Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, not intractable, without status epilepticus
- with seizures of localized onset G40.009 — Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, not intractable, without status epilepticus
- intractable G40.019 — Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, intractable, without status epilepticus
- with status epilepticus G40.011 — Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, intractable, with status epilepticus
- without status epilepticus G40.019 — Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, intractable, without status epilepticus
- not intractable G40.009 — Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, not intractable, without status epilepticus
- with status epilepticus G40.001 — Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, not intractable, with status epilepticus
- without status epilepticus G40.009 — Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, not intractable, without status epilepticus
- symptomatic
- with complex partial seizures G40.209 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with complex partial seizures, not intractable, without status epilepticus
- intractable G40.219 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with complex partial seizures, intractable, without status epilepticus
- with status epilepticus G40.211 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with complex partial seizures, intractable, with status epilepticus
- without status epilepticus G40.219 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with complex partial seizures, intractable, without status epilepticus
- not intractable G40.209 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with complex partial seizures, not intractable, without status epilepticus
- with status epilepticus G40.201 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with complex partial seizures, not intractable, with status epilepticus
- without status epilepticus G40.209 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with complex partial seizures, not intractable, without status epilepticus
- with simple partial seizures G40.109 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures, not intractable, without status epilepticus
- intractable G40.119 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures, intractable, without status epilepticus
- with status epilepticus G40.111 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures, intractable, with status epilepticus
- without status epilepticus G40.119 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures, intractable, without status epilepticus
- not intractable G40.109 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures, not intractable, without status epilepticus
- with status epilepticus G40.101 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures, not intractable, with status epilepticus
- without status epilepticus G40.109 — Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures, not intractable, without status epilepticus
- specified NEC G40.802 — Other epilepsy, not intractable, without status epilepticus
- intractable G40.804 — Other epilepsy, intractable, without status epilepticus
- with status epilepticus G40.803 — Other epilepsy, intractable, with status epilepticus
- without status epilepticus G40.804 — Other epilepsy, intractable, without status epilepticus
- not intractable G40.802 — Other epilepsy, not intractable, without status epilepticus
- with status epilepticus G40.801 — Other epilepsy, not intractable, with status epilepticus
- without status epilepticus G40.802 — Other epilepsy, not intractable, without status epilepticus
- tonic (-clonic)
- twilight F05 — Delirium due to known physiological condition
- uncinate (gyrus)
- Unverricht (-Lundborg) (familial myoclonic)
- visceral
- visual
Common questions about epilepsy ICD-10 codes
What is the ICD-10 code for epilepsy?
- G40.909 — Epilepsy, unspecified, not intractable, without status epilepticus. More specific codes apply when the documentation supports them: G40.80, G40.A09, G40.A19, G40.A11 and others below.
What is the ICD-10 code for benign myoclonic in infancy epilepsy?
- G40.80 — Other epilepsy (header code; choose a more specific subcode).
What is the ICD-10 code for cysticercosis epilepsy?
- B69.0 — Cysticercosis of central nervous system.
What is the ICD-10 code for deterioration epilepsy?
- F06.8 — Other specified mental disorders due to known physiological condition.
What is the ICD-10 code for intractable epilepsy?
- G40.919 — Epilepsy, unspecified, intractable, without status epilepticus.
What is the ICD-10 code for juvenile absence epilepsy?
- G40.A09 — Absence epileptic syndrome, not intractable, without status epilepticus.
What is the ICD-10 code for juvenile myoclonic epilepsy?
- G40.B09 — Juvenile myoclonic epilepsy, not intractable, without status epilepticus.
Is G40.909 billable?
- Yes. G40.909 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can G40.909 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict G40.909 as a principal diagnosis.
Is G40.909 a CC or MCC?
- No. G40.909 is neither a CC nor an MCC under MS-DRG v44.0.