ICD-9-CM Diagnosis Code 339.00
Diagnosis Code: 339.00 (Raw: 33900)
Description: Cluster headache syndrome, unspecified
Classification: International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM)
Fiscal Year: 2026 Reference
CMS Section 111 Status: Valid for reporting.
Overview & Historical Usage
ICD-9-CM code 339.00 is designated for Cluster headache syndrome, unspecified. While superseded by ICD-10 for current healthcare encounters, it remains a recognized reference code for CMS Section 111 reporting, legacy claims adjudication, and historical clinical data analysis.