G40.84
KCNQ2-related epilepsy
G40.84 is a non-billable ICD-10-CM code header for KCNQ2-related epilepsy. Report a more specific code from it instead. It is part of the FY2027 code set, effective October 1, 2026. The more specific codes under it are 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 and G40.844 KCNQ2-related epilepsy, intractable, without status epilepticus. Its coding notes include 5 Excludes1 entries and 12 Excludes2 entries.
Excludes1
Not coded here. The listed conditions generally should not be reported together.
Excludes2
Not included here. Both codes may be reported if the patient has both conditions.
Also from chapter/block level (8 notes)
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Notes
- the following terms are to be considered equivalent to intractable: pharmacoresistant (pharmacologically resistant), treatment resistant, refractory (medically) and poorly controlled
More specific codes under G40.84 4
- G40.841KCNQ2-related epilepsy, not intractable, with status epilepticusBillable
- G40.842KCNQ2-related epilepsy, not intractable, without status epilepticusBillable
- G40.843KCNQ2-related epilepsy, intractable, with status epilepticusBillable
- G40.844KCNQ2-related epilepsy, intractable, without status epilepticusBillable