ICD-10 Code for Epilepsy
Also indexed as (attack) (cerebral) (convulsion) (fit) (seizure)
The ICD-10-CM code for epilepsy is G40.909 — Epilepsy, unspecified, not intractable, without status epilepticus. This is the code the Alphabetic Index gives for epilepsy with no further qualifier, valid for FY2027 (October 1, 2026 – September 30, 2027).
BillableUnspecified
G40.909 is billable but unspecified. If the documentation names a type, site or cause, one of the more specific codes below is likely expected.
Which epilepsy code should you use?
The Alphabetic Index lists 59 codes under Epilepsy, epileptic, epilepsia. Which one applies depends on the qualifier documented in the record — the type, site, cause, or associated condition. Find the qualifier below, then verify the code in the Tabular List before using it.
By type
| benign myoclonic in infancy | G40.80 | Other epilepsy | not billable |
| cysticercosis | B69.0 | Cysticercosis of central nervous system | |
| deterioration | F06.8 | Other specified mental disorders due to known physiological condition | |
| due to syphilis | A52.19 | Other symptomatic neurosyphilis | |
| intractable | G40.919 | Epilepsy, unspecified, intractable, without status epilepticus | |
| juvenile absence | G40.A09 | Absence epileptic syndrome, not intractable, without status epilepticus | |
| juvenile myoclonic | G40.B09 | Juvenile myoclonic epilepsy, not intractable, without status epilepticus | |
| KCNQ2-related | G40.842 | KCNQ2-related epilepsy, not intractable, without status epilepticus | |
| Lafora progressive myoclonus | G40.C09 | Lafora progressive myoclonus epilepsy, not intractable, without status epilepticus | |
| not intractable | G40.909 | Epilepsy, unspecified, not intractable, without status epilepticus | |
| parasitic NOS | B71.9 | Cestode infection, unspecified | |
| partialis continua | G40.1 | Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures | not billable |
| polymorphic, in infancy | G40.83 | Dravet syndrome | not billable |
| spasms | G40.822 | Epileptic spasms, not intractable, without status epilepticus | |
| specified NEC | G40.802 | Other epilepsy, not intractable, without status epilepticus | |
| twilight | F05 | Delirium due to known physiological condition |
Epilepsy childhood
| absence | G40.A09 | Absence epileptic syndrome, not intractable, without status epilepticus | |
| absence › intractable | G40.A19 | Absence epileptic syndrome, intractable, without status epilepticus | |
| absence › not intractable | G40.A09 | Absence epileptic syndrome, not intractable, without status epilepticus | |
| absence › intractable › with status epilepticus | G40.A11 | Absence epileptic syndrome, intractable, with status epilepticus | |
| absence › intractable › without status epilepticus | G40.A19 | Absence epileptic syndrome, intractable, without status epilepticus | |
| absence › not intractable › with status epilepticus | G40.A01 | Absence epileptic syndrome, not intractable, with status epilepticus | |
| absence › not intractable › without status epilepticus | G40.A09 | Absence epileptic syndrome, not intractable, without status epilepticus |
Epilepsy generalized
| idiopathic | 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 | |
| idiopathic › intractable | G40.319 | Generalized idiopathic epilepsy and epileptic syndromes, intractable, without status epilepticus | |
| idiopathic › not intractable | G40.309 | Generalized idiopathic epilepsy and epileptic syndromes, not intractable, without status epilepticus | |
| specified NEC › intractable | G40.419 | Other generalized epilepsy and epileptic syndromes, intractable, without status epilepticus | |
| specified NEC › not intractable | G40.409 | Other generalized epilepsy and epileptic syndromes, not intractable, without status epilepticus | |
| idiopathic › intractable › with status epilepticus | G40.311 | Generalized idiopathic epilepsy and epileptic syndromes, intractable, with status epilepticus | |
| idiopathic › intractable › without status epilepticus | G40.319 | Generalized idiopathic epilepsy and epileptic syndromes, intractable, without status epilepticus | |
| idiopathic › not intractable › with status epilepticus | G40.301 | Generalized idiopathic epilepsy and epileptic syndromes, not intractable, with status epilepticus | |
| idiopathic › not intractable › without status epilepticus | G40.309 | Generalized idiopathic epilepsy and epileptic syndromes, not intractable, without status epilepticus | |
| specified NEC › intractable › with status epilepticus | G40.411 | Other generalized epilepsy and epileptic syndromes, intractable, with status epilepticus | |
| specified NEC › intractable › without status epilepticus | G40.419 | Other generalized epilepsy and epileptic syndromes, intractable, without status epilepticus | |
| specified NEC › not intractable › with status epilepticus | G40.401 | Other generalized epilepsy and epileptic syndromes, not intractable, with status epilepticus | |
| specified NEC › not intractable › without status epilepticus | G40.409 | Other generalized epilepsy and epileptic syndromes, not intractable, without status epilepticus |
Epilepsy intractable
Epilepsy juvenile absence
| intractable | G40.A19 | Absence epileptic syndrome, intractable, without status epilepticus | |
| not intractable | G40.A09 | Absence epileptic syndrome, not intractable, without status epilepticus | |
| intractable › with status epilepticus | G40.A11 | Absence epileptic syndrome, intractable, with status epilepticus | |
| intractable › without status epilepticus | G40.A19 | Absence epileptic syndrome, intractable, without status epilepticus | |
| not intractable › with status epilepticus | G40.A01 | Absence epileptic syndrome, not intractable, with status epilepticus | |
| not intractable › without status epilepticus | G40.A09 | Absence epileptic syndrome, not intractable, without status epilepticus |
Epilepsy juvenile myoclonic
| intractable | G40.B19 | Juvenile myoclonic epilepsy, intractable, without status epilepticus | |
| not intractable | G40.B09 | Juvenile myoclonic epilepsy, not intractable, without status epilepticus | |
| intractable › with status epilepticus | G40.B11 | Juvenile myoclonic epilepsy, intractable, with status epilepticus | |
| intractable › without status epilepticus | G40.B19 | Juvenile myoclonic epilepsy, intractable, without status epilepticus | |
| not intractable › with status epilepticus | G40.B01 | Juvenile myoclonic epilepsy, not intractable, with status epilepticus | |
| not intractable › without status epilepticus | G40.B09 | Juvenile myoclonic epilepsy, not intractable, without status epilepticus |
Epilepsy KCNQ2-related
| intractable | G40.844 | KCNQ2-related epilepsy, intractable, without status epilepticus | |
| not intractable | G40.842 | KCNQ2-related epilepsy, not intractable, without status epilepticus | |
| intractable › with status epilepticus | G40.843 | KCNQ2-related epilepsy, intractable, with status epilepticus | |
| intractable › without status epilepticus | G40.844 | KCNQ2-related epilepsy, intractable, without status epilepticus | |
| not intractable › with status epilepticus | G40.841 | KCNQ2-related epilepsy, not intractable, with status epilepticus | |
| not intractable › without status epilepticus | G40.842 | KCNQ2-related epilepsy, not intractable, without status epilepticus |
Epilepsy localization-related
| idiopathic | G40.009 | Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, not intractable, without status epilepticus | |
| idiopathic › 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 | |
| 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 | |
| symptomatic › with simple partial seizures | G40.109 | Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures, not intractable, without status epilepticus | |
| idiopathic › with seizures of localized onset › intractable | G40.019 | Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, intractable, without status epilepticus | |
| idiopathic › with seizures of localized onset › not intractable | 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 › intractable | G40.219 | Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with complex partial seizures, intractable, without status epilepticus | |
| symptomatic › with complex partial seizures › not intractable | G40.209 | Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with complex partial seizures, not intractable, without status epilepticus | |
| symptomatic › with simple partial seizures › intractable | G40.119 | Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures, intractable, without status epilepticus | |
| symptomatic › with simple partial seizures › not intractable | G40.109 | Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures, not intractable, without status epilepticus |
Epilepsy myoclonus, myoclonic
| severe, in infancy | G40.83 | Dravet syndrome | not billable |
| progressive › Lafora | G40.C09 | Lafora progressive myoclonus epilepsy, not intractable, without status epilepticus | |
| progressive › Lafora › intractable | G40.C19 | Lafora progressive myoclonus epilepsy, intractable, without status epilepticus | |
| progressive › Lafora › not intractable | G40.C09 | Lafora progressive myoclonus epilepsy, not intractable, without status epilepticus |
Epilepsy not intractable
Epilepsy progressivemyoclonic
| Lafora | G40.C09 | Lafora progressive myoclonus epilepsy, not intractable, without status epilepticus |
Epilepsy related to
| alcohol | 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 | |
| external causes | 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 | |
| sleep deprivation | 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 | |
| alcohol › not intractable | G40.509 | Epileptic seizures related to external causes, not intractable, without status epilepticus | |
| drugs › not intractable | G40.509 | Epileptic seizures related to external causes, not intractable, without status epilepticus | |
| external causes › not intractable | G40.509 | Epileptic seizures related to external causes, not intractable, without status epilepticus | |
| hormonal changes › not intractable | G40.509 | Epileptic seizures related to external causes, not intractable, without status epilepticus | |
| sleep deprivation › not intractable | G40.509 | Epileptic seizures related to external causes, not intractable, without status epilepticus | |
| stress › not intractable | G40.509 | Epileptic seizures related to external causes, not intractable, without status epilepticus | |
| alcohol › not intractable › with status epilepticus | G40.501 | Epileptic seizures related to external causes, not intractable, with status epilepticus | |
| alcohol › not intractable › without status epilepticus | G40.509 | Epileptic seizures related to external causes, not intractable, without status epilepticus | |
| drugs › not intractable › with status epilepticus | G40.501 | Epileptic seizures related to external causes, not intractable, with status epilepticus | |
| drugs › not intractable › without status epilepticus | G40.509 | Epileptic seizures related to external causes, not intractable, without status epilepticus | |
| external causes › not intractable › with status epilepticus | G40.501 | Epileptic seizures related to external causes, not intractable, with status epilepticus | |
| external causes › not intractable › without status epilepticus | G40.509 | Epileptic seizures related to external causes, not intractable, without status epilepticus | |
| hormonal changes › not intractable › with status epilepticus | G40.501 | Epileptic seizures related to external causes, not intractable, with status epilepticus | |
| hormonal changes › not intractable › without status epilepticus | G40.509 | Epileptic seizures related to external causes, not intractable, without status epilepticus | |
| sleep deprivation › not intractable › with status epilepticus | G40.501 | Epileptic seizures related to external causes, not intractable, with status epilepticus | |
| sleep deprivation › not intractable › without status epilepticus | G40.509 | Epileptic seizures related to external causes, not intractable, without status epilepticus | |
| stress › not intractable › with status epilepticus | G40.501 | Epileptic seizures related to external causes, not intractable, with status epilepticus | |
| stress › not intractable › without status epilepticus | G40.509 | Epileptic seizures related to external causes, not intractable, without status epilepticus |
Epilepsy spasms
| intractable | G40.824 | Epileptic spasms, intractable, without status epilepticus | |
| not intractable | G40.822 | Epileptic spasms, not intractable, without status epilepticus | |
| intractable › with status epilepticus | G40.823 | Epileptic spasms, intractable, with status epilepticus | |
| intractable › without status epilepticus | G40.824 | Epileptic spasms, intractable, without status epilepticus | |
| not intractable › with status epilepticus | G40.821 | Epileptic spasms, not intractable, with status epilepticus | |
| not intractable › without status epilepticus | G40.822 | Epileptic spasms, not intractable, without status epilepticus |
Epilepsy specified NEC
| intractable | G40.804 | Other epilepsy, intractable, without status epilepticus | |
| not intractable | G40.802 | Other epilepsy, not intractable, without status epilepticus | |
| intractable › with status epilepticus | G40.803 | Other epilepsy, intractable, with status epilepticus | |
| intractable › without status epilepticus | G40.804 | Other epilepsy, intractable, without status epilepticus | |
| not intractable › with status epilepticus | G40.801 | Other epilepsy, not intractable, with status epilepticus | |
| not intractable › without status epilepticus | G40.802 | Other epilepsy, not intractable, without status epilepticus |
Epilepsy syndromes
| specified NEC | G40.802 | Other epilepsy, not intractable, without status epilepticus | |
| generalized › idiopathic | G40.309 | Generalized idiopathic epilepsy and epileptic syndromes, not intractable, without status epilepticus | |
| generalized › specified NEC | G40.409 | Other generalized epilepsy and epileptic syndromes, not intractable, without status epilepticus | |
| localization-related › idiopathic | G40.009 | Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, not intractable, without status epilepticus | |
| specified NEC › intractable | G40.804 | Other epilepsy, intractable, without status epilepticus | |
| specified NEC › not intractable | G40.802 | Other epilepsy, not intractable, without status epilepticus | |
| generalized › idiopathic › intractable | G40.319 | Generalized idiopathic epilepsy and epileptic syndromes, intractable, without status epilepticus | |
| generalized › idiopathic › not intractable | G40.309 | Generalized idiopathic epilepsy and epileptic syndromes, not intractable, without status epilepticus | |
| generalized › specified NEC › intractable | G40.419 | Other generalized epilepsy and epileptic syndromes, intractable, without status epilepticus | |
| generalized › specified NEC › not intractable | G40.409 | Other generalized epilepsy and epileptic syndromes, not intractable, without status epilepticus |
Index terms and codes are reproduced from the official ICD-10-CM FY2027 release. The Alphabetic Index is a finding aid — a code must always be verified in the Tabular List before it is reported. Data sources