Is G04 a billable code?
No. G04 is a header code that groups 14 more specific codes. Use one of the billable codes listed on this page instead.
ICD-10-CM FY2027 diagnosis code
G04: Encephalitis, myelitis and encephalomyelitis
Header code: not billableValid for dates of service October 1, 2026 to September 30, 2027
G04 groups related diagnoses under encephalitis, myelitis and encephalomyelitis. It cannot be used on a claim by itself. Choose the billable code below that matches the patient's record.
Billable codes under G04
- G04.00Acute disseminated encephalitis and encephalomyelitis, unspecified
- G04.01Postinfectious acute disseminated encephalitis and encephalomyelitis (postinfectious ADEM)
- G04.02Postimmunization acute disseminated encephalitis, myelitis and encephalomyelitis
- G04.1Tropical spastic paraplegia
- G04.2Bacterial meningoencephalitis and meningomyelitis, not elsewhere classified
- G04.30Acute necrotizing hemorrhagic encephalopathy, unspecified
- G04.31Postinfectious acute necrotizing hemorrhagic encephalopathy
- G04.32Postimmunization acute necrotizing hemorrhagic encephalopathy
- G04.39Other acute necrotizing hemorrhagic encephalopathy
- G04.81Other encephalitis and encephalomyelitis
- G04.82Acute flaccid myelitis
- G04.89Other myelitis
- G04.90Encephalitis and encephalomyelitis, unspecified
- G04.91Myelitis, unspecified
G04 questions
What does G04 mean?
G04 is the ICD-10-CM code for Encephalitis, myelitis and encephalomyelitis. It is in chapter 6, Diseases of the nervous system (G00-G99).
Code titles come from the official ICD-10-CM files published by the CDC National Center for Health Statistics. Always check payer rules and the clinical record before billing.