ICD-10 Code G03.1 – Chronic meningitis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code G03.1 – Chronic meningitis
What it is
Chronic meningitis is long-lasting inflammation of the meninges, the membranes around the brain and spinal cord. It usually develops over weeks to months and may have an infectious, inflammatory, or other underlying cause.
Clinical signs
Clinical features vary; refer to documentation. Common findings include persistent headache, neck stiffness, nausea, and neurologic symptoms that develop gradually rather than suddenly.
When to use this code
Use G03.1 when the provider documents chronic meningitis or a clearly chronic meningeal inflammatory process. Apply it when the record supports a prolonged course, even if the cause is still being evaluated. If the note only states meningitis without chronicity, check documentation.
Do not use for
Do not use this code for acute meningitis, aseptic meningitis without chronic documentation, or meningeal symptoms without a confirmed diagnosis. Check documentation if the condition is better described by another specific cause.
Coding tip
Code the chronic meningitis diagnosis only when the provider explicitly documents chronicity; otherwise, query for clarification.