ICD-10-CM G04.0: Acute disseminated encephalitis and encephalomyelitis (ADEM)

ICD-10-CM Diagnosis Code (2025)

Official Description for G04.0

Acute disseminated encephalitis and encephalomyelitis (ADEM)

Coding Notes & Guidelines for G04.0

Excludes1: Not Coded Here
  • acute necrotizing hemorrhagic encephalopathy (G04.3-)
  • other noninfectious acute disseminated encephalomyelitis (noninfectious ADEM) (G04.81)
Excludes1: Not Coded Here
  • post chickenpox encephalitis (B01.1)
  • post measles encephalitis (B05.0)
  • post measles myelitis (B05.1)
Use Additional Code

code to identify the vaccine (T50.A-, T50.B-, T50.Z-)

Inclusion Terms
  • Encephalitis, post immunization
  • Encephalomyelitis, post immunization

Parent Code (Less Specific):

About ICD-10-CM Code G04.0 (Acute disseminated encephalitis and encephalomyelitis)

ICD-10-CM code G04.0 is a billable or specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes. The 2025 edition of ICD-10-CM G04.0 became effective on October 1, 2024.

This page provides detailed information about G04.0 - Acute disseminated encephalitis and encephalomyelitis (ADEM). It includes common terminology, coding guidelines such as "Includes," "Excludes1," and "Excludes2" notes, and information on required 7th characters. Utilizing this information correctly is essential for accurate medical coding and claims submission for conditions like Acute disseminated encephalitis and encephalomyelitis.